Effects of caffeine on human health

Addressing nutritional issues and eating behaviours among university students: a narrative review

University life is a critical period for establishing healthy eating habits and attitudes. However, university students are at risk of developing poor eating habits due to various factors, including economic conditions, academic stress and lack of information about nutritional concepts. Poor diet quality leads to malnutrition or overnutrition, increasing the risk of preventable diseases. Food environments on university campuses also play a significant role in shaping the dietary habits of students, with the availability of and accessibility to healthy food options being important factors influencing food choices and overall diet quality. Disordered eating habits and body dissatisfaction are prevalent among university students and can lead to eating disorders. Income and living arrangements also influence dietary habits, with low household income and living alone being associated with unhealthy eating habits. This study is a narrative review that aimed to address nutritional issues and eating behaviours, specifically among university students. We investigated the eating behaviours of university students, including their dietary patterns, food choices and food environments. The objective of this review was to provide insights into the nutritional issues and eating behaviours of university students, with the aim of identifying target areas for intervention to improve the overall health and wellbeing among college students. University food environments need to be restructured to promote healthy eating, including the availability, accessibility, affordability and labelling of healthy foods, and policies to limit the availability of unhealthy foods and drinks on campus.

Tai Chi Chuan teaching on alleviating mental fatigue among college students: insights from ERPs

Background

Mental fatigue is a prevalent issue, especially among college students, which significantly impacts learning efficiency. Existing interventions like caffeine use have side-effects, highlighting the need for alternative approaches. Tai Chi Chuan (TCC), a traditional Chinese mind -body exercise, shows promise in alleviating mental fatigue, yet its neural mechanisms on alleviating mental fatigue, particularly from the perspective of inhibitory control, remain unclear.

Objectives

This study aimed to fill this gap by investigating the effects of TCC on mental fatigue and cognitive function in college students using ERP measures based on the Go/NoGo task.

Methods

Fifty-two healthy college students were randomly assigned to the TCC group (n = 18), aerobic exercise (AE) group (n = 17), or control (CON) group (n = 17). Mental fatigue was induced via the Stroop task, followed by a 20-min intervention of TCC practice, ergometer exercise, or sitting rest. Reaction time (RT), Visual Analog Scale (VAS) scores, and EEG data were collected.

Results

The data showed that after the Stroop task, all groups exhibited signs of mental fatigue, with increased VAS scores and RTs. However, following the 20-min intervention, the TCC group demonstrated more significant improvements in VAS scores, RTs, and ERP components (such as increased NoGo-P3 and Go-P3 amplitudes, shortened Go-P3 latencies, and decreased NoGo-N2 amplitudes) compared to the AE and CON groups.

Conclusion

These findings indicate that practicing TCC can effectively alleviate mental fatigue and facilitate cognitive recovery in college students after sustained cognitive tasks. This study provides new insights into the neural mechanisms of TCC's beneficial effects on alleviating mental fatigue.

The Role of Xenobiotic Caffeine on Cardiovascular Health: Promises and Challenges

Cardiovascular diseases (CVDs) represent a leading cause of premature mortality and disability worldwide, with their incidence expected to rise, potentially reaching 24 million deaths per year by 2030. These multifactorial diseases, including hypertension, coronary artery disease, arrhythmia, and heart failure, are often linked to metabolic disturbances such as diabetes, oxidative stress, endothelial dysfunction, and inflammation. Natural compounds, such as caffeine, have been explored for their potential therapeutic effects on CVDs. Caffeine, found in coffee, tea, cocoa, and various energy drinks, is a widely consumed psychoactive compound with noted analgesic and anti-inflammatory properties. Despite its long history of use, caffeine's impact on cardiovascular health remains controversial, with both beneficial and harmful effects reported. This review examines the current literature on the effects of caffeine on cardiovascular diseases (CVDs), with an emphasis on preclinical and clinical studies, its pharmacokinetic properties, and the molecular mechanisms it modulates. There is evidence that moderate caffeine intake can be beneficial for some CVDs, such as hypertension, while for other CVDs, such as dyslipidemia, the evidence collected so far suggests that caffeine intake could be detrimental since it increases total cholesterol levels. But variability in dosage, intake patterns, and individual factors (such as genetics and diet) complicates the reliability of results. Additionally, challenges related to dose standardization and the absence of consistent clinical trial designs hinder the full utilization of caffeine in CVD treatment. Nonetheless, caffeine appears to be safe for individuals without significant cardiovascular conditions. Future research should aim for well-designed studies with precise patient cohorts and standardized methodologies to better assess caffeine's role in CVD management.

Acute Cardiovascular Effects of Turkish Coffee Assessed by VO2 Test: A Randomized Crossover Trial

BACKGROUND

Turkish coffee (TC), a traditional unfiltered coffee preparation method, contains unique bioactive compounds due to its specific brewing process. While TC's cultural significance is well-documented, its acute physiological and psychological effects remain understudied.

OBJECTIVES

This randomized, controlled crossover trial investigated the acute effects of a standardized TC dose (3 mg caffeine/kg body weight) on metabolic and psychological parameters in healthy female university students (n = 52, age: 20.25 ± 1.20 years).

METHODS

TC was prepared with a 1:1 ratio of medium and dark roasted Arabica beans. The chemical analysis showed the caffeine content to be 2.8 ± 0.3 mg/mL and the chlorogenic acid content to be 1.9 ± 0.2 mg/ml. Participants were randomized to receive either TC or water control, with a washout period of 8 weeks between treatments. Cardiovascular parameters, metabolic markers, and validated visual analog scales (VAS) were assessed at baseline, 60-, 90-, and 120-min post-consumption.

RESULTS

Heart rate showed significant time-dependent reductions in both groups (control: p < 0.05; TC: p-value < 0.01 at 60, 90, and 120 min vs. baseline). Heart rate dropped significantly in the Turkish coffee group, from 78.0 ± 10.2 bpm at baseline to 71.5 ± 9.5 bpm after 90 min (p-value = 0.002). Sleep scores also declined, from 4.38 ± 2.91 at baseline to 1.88 ± 1.45 after 120 min (p < 0.05), indicating a stimulating effect of caffeine. TC consumption significantly affected appetite sensations (p < 0.05) and sleep scores (F = 3.174, p-value = 0.029), with the TC group showing progressive reductions in sleep scores from baseline (4.38 ± 2.91) to 60 min (2.58 ± 2.04), and further decreases at 90 and 120 min.

CONCLUSIONS

These findings suggest that TC exerts significant acute effects on cardiovascular function and psychophysiological parameters in healthy young females, potentially due to its unique phytochemical profile and preparation method.

Does Personality Modulate the Sensitivity to Contaminants? A Case Study with Cadmium and Caffeine

Personality has been reported to influence fish response to stress. This study aimed to assess whether shy and bold fish display different sensitivities to two environmental contaminants: caffeine (CAF) and cadmium (Cd). Thus, the sensitivity to Cd was compared based on lethal concentrations (LCs). The potential different response to CAF, known to alter the social behavior and locomotor activity of zebrafish, was studied using behavioral parameters. Overall, different LC values were found for each group: 48 h LC50 values of 4.79 (shy fish) and 8.20 mg·L-1 (bold fish); and 96 h LC50 values of 3.79 (shy fish) and 9.79 mg·L-1 (bold fish). In terms of response to CAF, a significant interaction between CAF and personality traits (bold and shy) was found in the locomotion activities (distance travelled, and medium and rapid movements), in the mirror test (frequency of contact and entries into the contact, approach, and distant zones), and in social tests (swimming distance in zones 2 and 3; time spent in zones 1, 2, and 3; and number of entries into zones 1 and 2). Shy fish exposed to 300 μg·L-1 of CAF presented hypoactivity, reduced aggressive behavior, and reduced sociability. Conversely, CAF did not influence the behavior of bold fish. In general, shy fish were more sensitive to Cd and exhibited anxious behavior when exposed to CAF, which appears to be the factor responsible for changes in their social behavior. Our results highlight the importance of taking personality traits into account in future studies, as variations in behavioral responses between bold and shy individuals can mask the toxicological effects of different chemicals.

Nutrition for Optimal Lactation

BACKGROUND

Breastfeeding is the ideal method of feeding for all newborns and is associated with multiple positive health outcomes. Human milk provides all essential nutrients and bioactive molecules needed for optimal infant health and development. Maternal nutrition during lactation plays an important role in supporting breastfeeding and in preventing nutrition and metabolic imbalances. The aim of this narrative review was to describe the most prevalent nutrition issues in lactating women and provide a summary of current diet recommendations as well as controversies on supplementation, in order to facilitate the information for clinicians and health professionals.

SUMMARY

Breastfeeding is a nutritionally demanding stage and adequate nutrition is key to avoid alterations in maternal nutritional status, to produce an adequate quantity of milk with good quality, and to avoid nutrition programming of diseases. Anemia and vitamin D, A, iodine, and iron deficiencies are common, while obesity and metabolic diseases keep rising. Inadequate maternal intake of many nutrients is also frequent in this stage.

Discovery and Characterization of a Distinctive Theaflavin-3-Gallate Isomer from Camellia ptilophylla with Potent Anticancer Properties Against Human Colorectal Carcinoma Cells

Theaflavins, as key bioactive compounds of black tea, are garnering increasing attention. However, research predominantly focuses on theaflavin monomers derived from the enzymatic oxidation of cis-type catechins. In this study, we identify a unique stereoisomer of theaflavin-3-gallate (TF-3-G), named isoneoTF-3-G, in black tea from Camellia ptilophylla (C. ptilophylla), which is rich in trans-catechins. IsoneoTF-3-G, a characteristic theaflavin of C. ptilophylla black tea, is formed by the oxidation of gallocatechin gallate and catechin. It exhibits a bright orange-red color and shows an [M+H]+ ion at m/z 717.1449 in positive electron spray ionization-mass spectrometry. Furthermore, isoneoTF-3-G demonstrates potent inhibitory effects on the proliferation of human colorectal carcinoma HCT116 cells, with a half-inhibitory concentration of 56.32 ± 0.34 μM. This study reveals that the mitochondrial pathway is involved in the apoptosis induction of HCT116 cells by isoneoTF-3-G. Specifically, isoneoTF-3-G leads to increased reactive oxygen species in HCT116 cells, decreased mitochondrial membrane potential, and the consequent release of cytochrome c from the mitochondria to the cytosol, activating caspase-9 and caspase-3, which further promotes the cleavage of poly(ADPribose) polymerase. The results of this study enhance our understanding of the composition and synthesis mechanisms of theaflavins and provide foundational evidence for the further development of isoneoTF-3-G and C. ptilophylla.

Molecular docking targeting autophagy pathway mediate abrogation of NASH by specific functional foods: update review

Autophagy is a very well-conserved self-digestive mechanism that transports unwanted or disposable cytoplasmic debris to lysosomes for destruction, including misfolded proteins and damaged organelles. Advanced liver illnesses can develop from the prevalent clinical condition known as non-alcoholic steatohepatitis (NASH). There is no effective treatment, is still unclear. Therefore, in order to create novel therapeutics, it is necessary to comprehend the pathogenic pathways causing disease onset and progression. Natural components from medicinal plants are currently the subject of a larger number of studies since they provide fresh promise for NASH. This review provided an overview of the aetiology of NASH, in addition the role of natural products as alternative or complementary therapeutic agent for management of NASH via autophagy induction. It was concluded that, alternative and complementary supplement of natural functional food as Arabica coffee that rich with chlorogenic acid targeting autophagy mechanism mediate amelioration effect of NASH.

An update on beverage consumption patterns and caffeine intakes in a representative sample of the US population

Caffeine is a popular stimulant, predominantly consumed from beverages. The caffeinated beverage marketplace is continually evolving resulting in considerable interest in understanding the impact caffeinated beverages have on levels of intakes. Therefore, estimates of caffeine intakes in the U.S. population were calculated using a recent 2022 beverage survey, the Kantar Worldpanel Enhanced Beverage Service. A nationally representative sample of 49,700 consumers (aged ≥2 years) completed a 1-day beverage intake survey which collected data on beverage type/category, amount and brand. Approximately 69% of the U.S. population consumed at least one caffeinated beverage per day. The mean (±SE) daily caffeine intake of caffeine consumers (age >2 years) from all beverages was 210 ± 1.5 mg. Caffeine intake was highest in consumers aged 50-64 years (246 ± 4.5 mg/day) and lowest in children aged 2-5 (42 ± 2.4 mg/day). At the 90th percentile intake was 520 mg/day for all ages combined. Coffee was the largest contributor (69%) to caffeine intake across all age groups followed by carbonated soft drinks (15.4%), tea (8.8%), and energy drinks (6.3%). This study indicates that an increase in caffeine intake has occurred with a corresponding shift in beverage consumption patterns compared to previous surveys.

Caffeine supplement, inflammation, and hepatic function in cirrhotic patients: A randomized, placebo- controlled, clinical trial

Aim

We investigated the possibility of caffeine supplementation for managing the inflammation, and hepatic function in cirrhotic patients.

Methods

In this randomized, double-blind, placebo-controlled trial, fifty patients with cirrhosis were randomly assigned to receive either caffeine supplement (400 mg), or placebo for eight weeks.

Results

The results indicated a significant decrease in AST, platelets (P = 0.002), and PTT (P < 0.001), in the caffeine group compared to the placebo group. Also, caffeine supplementation resulted in a significant reduction in inflammatory biomarkers compared to placebo (p < 0.05). A significant improvement in liver indices including AST to platelet ratio index (APRI), (P < 0.001). Fibrosis 4 score (P < 0.001), and MELD score (P = 0.034)., was observed after 8 weeks caffeine supplementation.

Conclusion

The results of the present study indicated that daily supplementation of 400 mg caffeine in cirrhotic patients can significantly improve liver fibrosis and reduce inflammatory factors.The trial was registered at the Iranian Registry of Clinical Trials (Registration ID: IRCT20100524004010N34).

Photophysical Properties, Fluorescence Quenching of Metformin Hydrochloride by Caffeine, and its Docking with the AMP-activated protein kinase receptor

In this research, the photophysical properties of metformin hydrochloride (MF-HCl) were studied using spectroscopic and molecular docking techniques. The interaction between metformin hydrochloride and caffeine is essential for understanding the pharmacokinetics of metformin, particularly in populations with high caffeine consumption. Metformin is a first-line medication for managing type 2 diabetes, while caffeine is a widely consumed dietary stimulant. Knowing how caffeine may affect the action of metformin is crucial for effective diabetes management. The spectroscopic techniques results showed that the photophysical properties (fluorescence quantum yields, lifetime, radiative, and non-radiative decay) of the drug are influenced by solvent polarity and drug concentration. The binding mechanism of metformin hydrochloride-caffeine (MF-HCl-CAF) was identified through the fluorescence quenching method. The quenching of drugs induced by caffeine is due to ground state complex formation. The binding occurs due to hydrogen bonds and Van der Waals forces in the reaction. The förster resonance energy transfer (FRET) between metformin hydrochloride and caffeine was also calculated using flourtools.com software. The threshold distance (R0), for 50% energy transfer from metformin hydrochloride to caffeine is 1.81 nm and the binding distance (r), between caffeine and the amino acid residue in metformin hydrochloride is 1.55 nm. Dynamic light scattering (DLS), Zeta potential, and Fourier transform infrared (FTIR) spectroscopy confirm the conformational change of the drugs, as the caffeine molecule binds to metformin hydrochloride molecules. The molecular docking of metformin hydrochloride with the amp-activated protein kinase receptor (PDB Id: 1z0n) is analyzed. Again the docking of both metformin hydrochloride and caffeine (two ligands) with the protein receptor (PDB Id: 1z0n) was also analyzed and the results agreed with the fluorescence quenching techniques.

Evaluation of sources, spatial and temporal distribution, ecological and health risk associated with CAF (Caffeine) and DEET (N, N-diethyl-meta-toluamide) contamination in the urban groundwater parts of Vellore city, Tamilnadu, India

Urban environments are heavily influenced by various activities, leading to contamination of water sources by emerging contaminants (ECs). Among these, caffeine (CAF) and N, N-diethyl-meta-toluamide (DEET) are notable ECs frequently found in domestic sewage due to human activities. Despite extensive research on emerging contaminants, limited studies have focused on the seasonal variations, human health and ecological risks of CAF and DEET in urban groundwater, particularly in Indian cities. This study aimed to analyze the occurrence, spatial distribution, ecological and health risks of CAF and DEET in groundwater in Vellore city, Tamil Nadu, India. A total of 96 groundwater samples were collected across four seasons in 2022 and analyzed using Hichrom HPLC in an 844 UV/VIS compact Ion Chromatography system. CAF and DEET were detected in 95% and 96% of samples, with mean concentrations of 34 μg/L and 30 μg/L, respectively. Contamination levels were higher during the Southwest Monsoon (SWM) and Northeast Monsoon (NEM) seasons. Health risk assessments for children, women, and men showed that CAF posed significant risks, particularly to children during the NEM season, followed by women and men. Although DEET exhibited lower health risks overall, children remained the most vulnerable group. Statistical analysis confirmed significant differences in exposure levels, with children showing the highest variations. Ecological risk assessment revealed that 96.88% of samples containing CAF posed moderate ecological risks, while 6.25% of DEET samples fell into the same category. This study highlights the widespread presence of CAF and DEET in urban groundwater and their associated health and ecological risks. The findings emphasize the need for effective strategies to monitor and mitigate EC contamination in urban water systems.

The effects of aerobic exercise and heat stress on the unbound fraction of caffeine

Introduction

The fraction of drug circulating in the blood that is not bound to plasma proteins (f u ) is considered pharmacologically active since it readily binds to its receptor. In vitro evidence suggests that changes in temperature and pH affect the affinity of drug binding to plasma proteins, resulting in changes in f u . In light of the well-established effects of exercise on body temperature and blood pH, we investigated whether an increase in blood temperature and decrease in pH facilitated through passive heating and exercise translated to a change in the f u of caffeine.

Methods

Ten healthy participants (4 females and 6 males; age: 21.9 ± 2.7 years [means ± SD]) ingested 3 mg/kg of anhydrous caffeine on two separate occasions comprised of a control trial involving 105 min of rest, and an experimental trial involving 10 min of passive heating, followed by 20 min of cycling at 55%V ˙ O 2 peak , and then 10 sprint intervals at 90%V ˙ O 2 peak . Venous blood was sampled and the plasma was processed via ultrafiltration to quantify the f u of caffeine and its major metabolite, paraxanthine.

Results

The exercise protocol resulted in maximal increases in core temperature of 1.37°C ± 0.27°C and lactate of 10.34 ± 3.33 mmol/L, and a decrease in blood pH of 0.12 ± 0.051 (all p < 0.05), which did not affect the f u of caffeine (baseline: 0.86 vs post-exercise: 0.75; p = 0.30) or paraxanthine (baseline: 0.59 vs. post-exercise: 0.70; p = 0.11). Furthermore, the rate of metabolism of caffeine assessed through the metabolic ratio ([paraxanthine]/[caffeine]) did not differ between resting and exercise trials.

Discussion

Therefore, the changes in blood temperature and pH in this study did not affect the f u of caffeine or paraxanthine.

Does music counteract mental fatigue? A systematic review

INTRODUCTION

Mental fatigue, a psychobiological state induced by prolonged and sustained cognitive tasks, impairs both cognitive and physical performance. Several studies have investigated strategies to counteract mental fatigue. However, potential health risks and contextual restrictions often limit these strategies, which hinder their practical application. Due to its noninvasive and portable nature, music has been proposed as a promising strategy to counteract mental fatigue. However, the effects of music on performance decrements vary with different music styles. Synthesizing studies that systematically report music style and its impact on counteracting performance decrements is crucial for theoretical and practical applications.

OBJECTIVES

This review aims to provide a comprehensive systematic analysis of different music styles in counteracting mental fatigue and their effects on performance decrements induced by mental fatigue. Additionally, the mechanisms by which music counteracts mental fatigue will be discussed.

METHODS

A comprehensive search was conducted across five databases-Web of Science, PubMed, SCOPUS, SPORTDiscus via EBSCOhost, and the Psychological and Behavioral Sciences Collection via EBSCOhost-up to November 18, 2023. The selected studies focused solely on music interventions, with outcomes including subjective feelings of mental fatigue, physiological markers, and both cognitive and behavioral performance.

RESULTS

Nine studies met the predetermined criteria for inclusion in this review. The types of music interventions that counteract mental fatigue include relaxing, exciting, and personal preference music, all of which were associated with decreased subjective feelings of mental fatigue and changes in objective physiological markers. Cognitive performance, particularly in inhibition and working memory tasks impaired by mental fatigue, was countered by both relaxing and exciting music. Exciting music was found to decrease reaction time more effectively than relaxing music in working memory tasks. The physiological marker of steady-state visually evoked potential-based brain-computer interface (SSVEP-BCI) amplitude increased, confirming that exciting music counteracts mental fatigue more effectively than relaxing music. Behavioral performance in tasks such as arm-pointing, the Yo-Yo intermittent test, and the 5 km time-trial, which were impaired by mental fatigue, were counteracted by personal preference music.

CONCLUSION

Relaxing music, exciting music, and personal preference music effectively counteract mental fatigue by reducing feelings of fatigue and mitigating performance decrements. Individuals engaged in mentally demanding tasks can effectively counteract concurrent or subsequent cognitive performance decrements by simultaneously listening to relaxing or exciting music without lyrics or by using music during recovery from mental fatigue. Exciting music is more effective than relaxing music in counteracting mental fatigue. Personal preference music is effective in counteracting behavioral performance decrements in motor control and endurance tasks. Mentally fatigued individuals could apply personal preference music to counteract subsequent motor control performance decrements or simultaneously listen to it to counteract endurance performance decrements. Future studies should specify and examine the effects of different music genres, tempos, and intensities in counteracting mental fatigue. Additionally, the role of music in counteracting mental fatigue in contexts such as work productivity, traffic accident risk, and sports requires further investigation, along with the underlying mechanisms.

Common Questions and Misconceptions About Energy Drinks: What Does the Scientific Evidence Really Show?

Energy drinks are a commonly consumed beverage, and studies suggest a possible performance-enhancing effect. A Google Scholar search using the keywords "energy drinks" and "exercise" yields numerous results, underscoring the voluminous research on this topic. However, there are questions regarding the effectiveness and safety of energy drinks. These questions include, but are not limited to: (1) What are the main active ingredients in energy drinks? (2) Do energy drinks assist in weight management? (3) Do energy drinks enhance aerobic performance? (4) Do energy drinks enhance athletic speed? (5) Do energy drinks improve reaction time? (6) Do energy drinks enhance lean tissue mass? (7) Can energy drinks improve cognitive performance? (8) Does the acute consumption of energy drinks elevate resting energy expenditure? (9) Is there any evidence to suggest that energy drinks are more effective than an identical serving of caffeine alone? (10) Are there sex differences in the response to energy drink consumption? (11) Do energy drinks affect sleep or sleepiness? (12) Should pregnant women avoid energy drinks? (13) Do energy drinks adversely affect cardiovascular function? (14) Does consuming energy drinks cause brain damage? (15) What are other safety considerations regarding energy drinks? (16) Is there any evidence to suggest that energy drinks are more effective than an identical serving of caffeine alone? (17) If caffeine is the main active ingredient in energy drinks and coffee, why is there a discrepancy in the adverse events reported for each? To address these questions, we performed an evidence-based scientific evaluation of the literature on energy drink supplementation.

Distribution and ecological risks of pharmaceuticals and personal care products with different anthropogenic pressures in typical watersheds in China

Due to global population growth and increased healthcare accessibility, pharmaceuticals and personal care products (PPCPs) are closely linked with human activities and have become new pollutants alongside some legacy priority pollutants, such as polycyclic aromatic hydrocarbons (PAHs). Although PPCPs have been detected in numerous river basins in recent years, a few researches have been carried out on their association with human activities. In this paper, the concentrations of PPCPs and toxicological data were compiled for over 25 representative watersheds in China in the past two decades from various sources, including PubMed, Elsevier and Springer. Comprehensive analysis of the occurrence, spatial distribution, sources and ecological risk assessment was carried out for the 30 most frequently detected PPCPs in water environments. Multivariate statistical methods, including hierarchical cluster analysis (HCA), principal component analysis (PCA) and redundancy analysis (RDA), were employed to classify PPCPs and assess their relationship with human activities. The results indicated that the concentrations of PPCPs in rivers varied significantly across studied regions, ranging from non-detect to 21,885 ng/L. Many detected compounds in PPCPs were antibiotics and their occurrence was closely linked with the economic development, effectiveness of medicines and geographical location. Household emissions were identified as the primary contributor to the occurrence of PPCPs in river basins. A strong correlation has been observed between PPCPs level and socio-economic indicators from multivariate statistical analysis. Ecological risk assessment revealed that caffeine (CAF), ibuprofen (IBU) and anhydroerythromycin (ERY) pose the greatest threat to aquatic life, particularly in the Northern China. The data compiled in this study provide insights into the impacts of PPCPs and the relationship of their ecological risks with various human activities, particularly in the typical Chinese river basins. Our results are valuable for the effective management PPCPs.

Coffee consumption and adverse cardiovascular events in patients with atrial fibrillation

BACKGROUND

There is some evidence of reduced major cardiovascular event (MACE) rates associated with moderate coffee consumption in the general population. However, there is concern about the potential risks of coffee consumption in patients with atrial fibrillation (AF). Therefore, we aimed to investigate the association between coffee consumption and MACE in AF patients.

METHODS

Data of patients with documented AF enrolled in two large prospective observational multicenter cohort studies (Swiss-AF and Beat-AF) were analyzed. Follow-up information was obtained on a yearly basis. Coffee consumption was categorized into two main groups: "daily" and "not-daily" coffee consumers as well as additional subcategories. The primary endpoint was MACE, defined as a composite of stroke or systemic embolism, myocardial infarction, hospitalization for acute heart failure, and cardiovascular mortality. Secondary endpoints were the individual components of MACE and all-cause mortality. We performed time-updated multivariable adjusted Cox regression analyses to investigate the association between coffee consumption and MACE.

RESULTS

The incidence rate for MACE was 5.09 per 100 person-years (py) in daily and 7.49 per 100 py in not-daily consumers (median follow-up duration: 4.7 years). After adjustment for pre-selected confounding variables, daily coffee consumption was associated with a 23% lower hazard for MACE compared to not-daily consumption (hazard ratio (HR) (95% confidence interval (CI)) 0.77 (0.66; 0.89)). Patients with moderate coffee consumption (2-3 cups/day) had the lowest hazard for MACE compared to patients with not-daily coffee consumption (HR (95% CI) 0.74 (0.63; 0.87)).

CONCLUSIONS

In a population of AF patients, daily coffee consumption was associated with a reduced risk for MACE, hospitalization for acute heart failure, and all-cause mortality. The results were inconclusive for stroke or systemic embolism, myocardial infarction, and cardiovascular death. In this analysis, we found no evidence of an unfavourable association of daily coffee consumption in AF Patients with adverse outcome events.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02105844.

Caffeine-Induced Upregulation of pas-1 and pas-3 Enhances Intestinal Integrity by Reducing Vitellogenin in Aged Caenorhabditis elegans Model

Background: Intestinal aging is characterized by declining protein homeostasis via reduced proteasome activity, which are hallmarks of age-related diseases. Our previous study showed that caffeine intake improved intestinal integrity with age by reducing vitellogenin (VIT, yolk protein) in C. elegans. In this study, we investigated the regulatory mechanisms by which caffeine intake improves intestinal integrity and reduces vitellogenin (VIT) production in aged Caenorhabditis elegans. Methods: We performed RNA-seq analysis, and qRT-PCR to validate and confirm the RNA-seq results. Transgenic worms with VIT-2::GFP and VIT-6::GFP were used for measuring VIT production. dsRNAi was conducted to elucidate the roles of pas-1 and pas-3 genes. Results:pas-1 and pas-3, a C. elegans ortholog of human PASM4, was upregulated by caffeine intake. They reduced VIT production by repressing unc-62, a transcriptional activator of vit expression. Interestingly, vit-2 was required for pas-1 and pas-3 expression, and RNAi of pas-1 and pas-3 promoted intestinal atrophy and colonization, suggesting a balancing mechanism for VIT levels in intestinal health. Additionally, lifespan was extended by caffeine intake (2 ± 0.05 days), however, this effect was not observed by pas-1 but not pas-3 RNAi, suggesting that the mode of action for an anti-aging effect of caffeine through pas-1 and pas-3 is distinctive. The lifespan extended by pas-1 was mediated by SKN-1 activation. Conclusions: Caffeine intake enhances intestinal health through proteasome activity and extends lifespan in aged C. elegans by upregulating pas-1 and pas-3. These findings suggest that caffeine consumption mitigates age-related proteasome impairment and maintains intestinal integrity during aging.

Dietary caffeine and its negative link to serum Klotho concentrations: evidence from the National Health and Nutrition Examination Survey

Background

This is the initial investigation assessing the association between caffeine consumption through diet and circulating Klotho concentrations, with Klotho being recognized as a key biomarker of healthspan and aging.

Methods

This cross-sectional analysis utilized data from 11,169 adults who participated in the National Health and Nutrition Examination Survey (NHANES). Caffeine consumption was evaluated using 24-h dietary recall interviews by trained professionals, and serum Klotho concentrations were measured via an enzyme-linked immunosorbent assay (ELISA). Generalized linear models and threshold effect analysis were employed to examine the relationship between caffeine intake and serum Klotho concentrations. Interaction tests and subgroup analyses were conducted to identify potential effect modifiers.

Results

After controlling for covariates, a negative correlation was observed between dietary caffeine consumption and serum Klotho concentrations, with each additional 100 mg of dietary caffeine consumption, Klotho decreased by 3.40 pg./mL (95% confidence interval [CI]: -5.73, -1.07). Participants in the fourth quartile of dietary caffeine consumption showed a 23.00 pg./mL reduction in serum Klotho concentrations (95% CI: -39.41, -6.58) compared to individuals in the first quartile. Threshold effect analysis revealed a threshold point corresponding to natural log-transformed caffeine value >3.74 (equivalent to ~41 mg/day), above which Klotho levels demonstrated a more pronounced decline. Subgroup analyses indicated that this association was more significant in participants with sedentary activity >480 min and without hypertension.

Conclusion

Our study reveals a significant, dose-dependent negative association linking caffeine intake with serum Klotho concentrations in the United States adults aged 40-79 years, with potential thresholds beyond which the effects become more pronounced. Additional studies are required to verify these results and investigate the underlying biological processes involved.

Paraxanthine provides greater improvement in cognitive function than caffeine after performing a 10-km run

RATIONALE

Intense exercise promotes fatigue and can impair cognitive function, particularly toward the end of competition when decision-making is often critical for success. For this reason, athletes often ingest caffeinated energy drinks prior to or during exercise to help them maintain focus, reaction time, and cognitive function during competition. However, caffeine habituation and genetic sensitivity to caffeine (CA) limit efficacy. Paraxanthine (PX) is a metabolite of caffeine reported to possess nootropic properties. This study examined whether ingestion of PX with and without CA affects pre- or post-exercise cognitive function.

METHODS

12 trained runners were randomly assigned to consume in a double-blind, randomized, and crossover manner 400 mg of a placebo (PL); 200 mg of PL + 200 mg of CA; 200 mg of PL + 200 mg of PX (ENFINITY®, Ingenious Ingredients); or 200 mg PX + 200 mg of CA (PX+CA) with a 7-14-day washout between treatments. Participants donated fasting blood samples and completed pre-supplementation (PRE) side effects questionnaires, the Berg-Wisconsin Card Sorting Test (BCST), and the Psychomotor Vigilance Task Test (PVTT). Participants then ingested the assigned treatment and rested for 60 minutes, repeated tests (PRE-EX), performed a 10-km run on a treadmill at a competition pace, and then repeated tests (POST-EX). Data were analyzed using General Linear Model (GLM) univariate analyses with repeated measures and percent changes from baseline with 95% confidence intervals.

RESULTS

BCST correct responses in the PX treatment increased from PRE-EX to POST-EX (6.8% [1.5, 12.1], p = 0.012). The error rate in the PL (23.5 [-2.8, 49.8] %, p = 0.078) and CA treatment (31.5 [5.2, 57.8] %, p = 0.02) increased from PRE-EX values with POST-EX errors tending to be lower with PX treatment compared to CA (-35.7 [-72.9, 1.4] %, p = 0.059). POST-EX perseverative errors with PAR rules were significantly lower with PX treatment than with CA (-26.9 [-50.5, -3.4] %, p = 0.026). Vigilance analysis revealed a significant interaction effect in Trial #2 mean reaction time values (p = 0.049, η p 2 = 0.134, moderate to large effect) with POST-EX reaction times tending to be faster with PX and CA treatment. POST-EX mean reaction time of all trials with PX treatment was significantly faster than PL (-23.2 [-43.4, -2.4] %, p = 0.029) and PX+CA (-29.6 [-50.3, -8.80] %, p = 0.006) treatments. There was no evidence that PX ingestion adversely affected ratings of side effects associated with stimulant intake or clinical blood markers.

CONCLUSIONS

Results provide some evidence that pre-exercise PX ingestion improves prefrontal cortex function, attenuates attentional decline, mitigates cognitive fatigue, and improves reaction time and vigilance. Adding CA to PX did not provide additional benefits. Therefore, PX ingestion may serve as a nootropic alternative to CA.

Common questions and misconceptions about caffeine supplementation: what does the scientific evidence really show?

Caffeine is a popular ergogenic aid that has a plethora of evidence highlighting its positive effects. A Google Scholar search using the keywords "caffeine" and "exercise" yields over 200,000 results, emphasizing the extensive research on this topic. However, despite the vast amount of available data, it is intriguing that uncertainties persist regarding the effectiveness and safety of caffeine. These include but are not limited to: 1. Does caffeine dehydrate you at rest? 2. Does caffeine dehydrate you during exercise? 3. Does caffeine promote the loss of body fat? 4. Does habitual caffeine consumption influence the performance response to acute caffeine supplementation? 5. Does caffeine affect upper vs. lower body performance/strength differently? 6. Is there a relationship between caffeine and depression? 7. Can too much caffeine kill you? 8. Are there sex differences regarding caffeine's effects? 9. Does caffeine work for everyone? 10. Does caffeine cause heart problems? 11. Does caffeine promote the loss of bone mineral? 12. Should pregnant women avoid caffeine? 13. Is caffeine addictive? 14. Does waiting 1.5-2.0 hours after waking to consume caffeine help you avoid the afternoon "crash?" To answer these questions, we performed an evidence-based scientific evaluation of the literature regarding caffeine supplementation.

Risk of metabolic syndrome linked to tobacco smoking and caffeine consumption among Palestinian university students

OBJECTIVES

The aim of the study was to determine the prevalence of metabolic syndrome (MetS) and its association with the use of tobacco smoking and caffeine consumption among Palestinian university students.

METHODS

A cross-sectional study was conducted in 2020 among university students at An-Najah National University in the West Bank. MetS was diagnosed according to the National Cholesterol Education Programme. We employed adjusted multiple logistic regression models to address the association between MetS and tobacco smoking and caffeine consumption.

RESULTS

The number of participants was 392. The findings revealed that 9.2% of the students met the diagnostic criteria for MetS, with a significantly higher prevalence in males (14.1%) than females (4.8%) (p = 0.001). The study highlighted various substance use rates among participants: 20.2% smoked cigarettes, 28.6% smoked waterpipes, 5.6% smoked e-cigarettes, and 39% consumed energy drinks. Coffee (83.9%) and black tea (84.7%) were also widely consumed. Mean values of triglyceride level (p = 0.006), systolic blood pressure (p < 0.001), and diastolic blood pressure (p = 0.016) were higher in cigarette smokers than nonsmokers. Energy drink consumers had higher levels of triglycerides than non-consumers (p = 0.015). Tea consumers had decreased mean values of fast blood sugar (p = 0.020) than non-users. The adjusted binary regression revealed that cigarette smokers were at greater risk of MetS (OR = 3.48, p = 0.009), and black tea consumers were less likely to have MetS (OR = 0.37, p = 0.032). Furthermore, increased BMI was associated with an increased risk of MetS (OR = 1.09, p = 0.008). Moreover, waterpipe smokers were at a higher risk of having high triglyceride levels (OR = 5.18, p = 0.027).

CONCLUSION

The study illustrates the health implications of tobacco and energy drink consumption on MetS among Palestinian university students, underlining waterpipe smoking as a pressing health concern linked to elevated triglycerides. These results clarify the MetS burden in Palestine and explore new risks and protective factors.

Screening the quality of legal and illegal dietary supplements by LC-MS/MS

Dietary supplements are widely consumed. However, the lack of mandatory testing results in limited data on their quality, particularly in Eastern Europe. In this study, 21 legally registered and 9 illegal supplements, seized from an underground facility by the Polish Police, were examined. Contaminants were screened by utilising high-performance liquid chromatography coupled with untargeted mass spectrometry. The analysis identified 32 contaminants in the 30 dietary supplements examined. Untargeted analysis revealed a concerning issue: the intentional adulteration of both legal and illegal supplements with pharmacologically active substances that are prohibited in this category of products. This study indicated that many dietary supplements are of low quality due to deliberate adulteration or inadequate manufacturing conditions. The presence of unregistered or unapproved substances in these supplements poses serious health risks. Strong legal regulations are essential to address this issue effectively.

Enhanced degradation of aqueous caffeine via cylindrical dielectric barrier discharge plasma: Efficacy and toxicity insights

An environmentally friendly approach for caffeine degradation was explored in this study utilizing cylindrical dielectric barrier discharge (CDBD) plasma. The current-voltage characteristics and the plasma parameters of the CDBD, such as the electron temperature, electron density, density of nitrogen excited states, vibrational temperature, and rotational temperature, were assessed through electrical and optical characterization respectively. Fourier-transform infrared spectroscopy (FTIR) was employed to evaluate the reactive oxygen and nitrogen species (RONS) in the plasma-treated air. The physicochemical properties of deionized water (DW) were measured. To gain a deeper insight into the role of RONS in caffeine degradation, their concentrations in DW were analyzed. Furthermore, the effects of initial concentration, sample volume, and pH on caffeine degradation were investigated. The highest degradation of caffeine was 94% at initial concentration of 50 mg L-1, sample volume 50 mL and in neutral pH. Liquid chromatography-mass spectrometry (LC-MS) was then used to propose the degradation pathway for caffeine. The major reactive species involved in caffeine degradation was ozone. Finally, the phytotoxicity and cytotoxicity of caffeine were assessed before and after plasma treatment with plasma-treated caffeine (PTC) showing minimal toxicity to both plants and cells.

When to sleep and consume caffeine to boost alertness

STUDY OBJECTIVES

Sleep loss can cause cognitive impairments that increase the risk of mistakes and accidents. However, existing guidelines to counteract the effects of sleep loss are generic and are not designed to address individual-specific conditions, leading to suboptimal alertness levels. Here, we developed an optimization algorithm that automatically identifies sleep schedules and caffeine-dosing strategies to minimize alertness impairment due to sleep loss for desired times of the day.

METHODS

We combined our previous algorithms that separately optimize sleep or caffeine to simultaneously identify the best sleep schedules and caffeine doses that minimize alertness impairment at desired times. The optimization algorithm uses the predictions of the well-validated Unified Model of Performance to estimate the effectiveness and physiological feasibility of a large number of possible solutions and identify the best one. To assess the optimization algorithm, we used it to identify the best sleep schedules and caffeine-dosing strategies for four studies that exemplify common sleep-loss conditions and compared the predicted alertness-impairment reduction achieved by using the algorithm's recommendations against that achieved by following the U.S. Army caffeine guidelines.

RESULTS

Compared to the alertness-impairment levels in the original studies, the algorithm's recommendations reduced alertness impairment on average by 63%, an improvement of 24 percentage points over the U.S. Army caffeine guidelines.

CONCLUSIONS

We provide an optimization algorithm that simultaneously identifies effective and safe sleep schedules and caffeine-dosing strategies to minimize alertness impairment at user-specified times.

How Does the Powder Mixture of Ibuprofen and Caffeine Attenuate the Solubility of Ibuprofen? Comparative Study for the Xanthine Derivatives to Recognize Their Intermolecular Interactions Using Fourier-Transform Infrared (FTIR) Spectra, Differential Scanning Calorimetry (DSC), and X-ray Powder Diffractometry (XRPD)

Molecular interactions between active pharmaceutical ingredients (APIs) and xanthine (XAT) derivatives were analyzed using singular value decomposition (SVD). XAT derivatives were mixed with equimolar amounts of ibuprofen (IBP) and diclofenac (DCF), and their dissolution behaviors were measured using high-performance liquid chromatography. The solubility of IBP decreased in mixtures with caffeine (CFN) and theophylline (TPH), whereas that of DCF increased in mixtures with CFN and TPH. No significant differences were observed between the mixtures of theobromine (TBR) or XAT with IBP and DCF. Mixtures with various molar ratios were analyzed using differential scanning calorimetry, X-ray powder diffraction, and Fourier-transform infrared spectroscopy to further explore these interactions. The results were subjected to SVD. This analysis provides valuable insights into the differences in interaction strength and predicted interaction sites between XAT derivatives and APIs based on the combinations that form mixtures. The results also showed the impact of the XAT derivatives on the dissolution behavior of IBP and DCF. Although IBP and DCF were found to form intermolecular interactions with CFN and TPH, these effects resulted in a reduction of the solubility of IBP and an increase in the solubility of DCF. The current approach has the potential to predict various interactions that may occur in different combinations, thereby contributing to a better understanding of the impact of health supplements on pharmaceuticals.

The Effects of Caffeine on Blood Platelets and the Cardiovascular System through Adenosine Receptors

Caffeine is the most popular and widely consumed behaviourally active substance in the world. This review describes the influence of caffeine on the cardiovascular system, with a special focus on blood platelets. For many years, caffeine was thought to have a negative effect on the cardiovascular system mainly due to increasing blood pressure. However, more recent data suggest that habitual caffeine consumption may reduce the risk of cardiovascular disease and hypertension. This could be a significant finding as cardiovascular disease is the leading cause of death worldwide. Caffeine is known to inhibit A1 adenosine receptors, through which it is believed to modulate inter alia coronary blood flow, total peripheral resistance, diuresis, and heart rate. It has been shown that coffee possesses antiplatelet activity, but depending on the dose and the term of its use, caffeine may stimulate or inhibit platelet reactivity. Also, chronic exposure to caffeine may sensitize or upregulate the adenosine receptors in platelets causing increased cAMP accumulation and anti-aggregatory effects and decrease calcium levels elicited by AR agonists. The search for new, selective, and safe AR agonists is one of the new strategies for improving antiplatelet therapy involving targeting multiple pathways of platelet activation. Therefore, this review examines the AR-dependent impact of caffeine on blood platelets in the presence of adenosine receptor agonists.

Effects of post-fermentation addition of green tea extract for sulfur dioxide replacement on Sauvignon Blanc wine phenolic composition, antioxidant capacity, colour, and mouthfeel attributes

This study examines the feasibility of replacing SO2 in a New Zealand Sauvignon Blanc wine with a green tea extract. The treatments included the control with no preservatives (C), the addition of green tea extract at 0.1 and 0.2 g/L (T1 and T2), and an SO2 treatment at 50 mg/L (T3). Five monomeric phenolic compounds were detected in the green tea extract used for the experiment, and their concentrations ranged in the order (-)-epigallocatechin gallate > (-)-epigallocatechin > (-)-epicatechin > (-)-epicatechin gallate > gallic acid. At the studied addition rates, these green tea-derived phenolic compounds contributed to ∼70% of the antioxidant capacity (ABTS), ∼71% of the total phenolic index (TPI), and ∼ 84% of tannin concentration (MCPT) of the extract dissolved in a model wine solution. Among wine treatments, T1 and T2 significantly increased the wine's colour absorbance at 420 nm, MCPT, gallic acid and total monomeric phenolic content. TPI and ABTS were significantly higher in wines with preservatives (i.e., T2 > T1 ≅ T3 > C, p < 0.05). These variations were observed both two weeks after the treatments and again after five months of wine aging. Additionally, an accelerated browning test and a quantitative sensory analysis of wine colour and mouthfeel attributes were performed after 5 months of wine aging. When exposed to excessive oxygen and high temperature (50 °C), T1 and T2 exhibited ∼29% and 24% higher browning capacity than the control, whereas T3 reduced the wine's browning capacity by ∼20%. Nonetheless, the results from sensory analysis did not show significant variations between the treatments. Thus, using green tea extract to replace SO2 at wine bottling appears to be a viable option, without inducing a negative impact on the perceptible colour and mouthfeel attributes of Sauvignon Blanc wine.

Molecular targets of caffeine in the central nervous system

Caffeine is an alkaloid obtained from plants and is one of the most consumptive drug in the form of chocolate, coffee and beverages. The potential impact of caffeine within CNS can be easily understood by mechanism of action-antagonism of adenosine receptor, calcium influx, inhibits phosphodiesterases. Adenosine a neuromodulator for adenosine receptors, which are abundantly expressed within the central nervous system. Caffeine antagonized the adenosine receptor, hence stimulate expression of dopamine. It plays pivotal role in many metabolic pathways within the brain and nervous system, it reduced the amyloid-β-peptide (Aβ) accumulation, downregulation of tau protein phosphorylation, stimulate cholinergic neurons and inhibits the acetylcholinestrase (AChE). It also possess antioxidant and antiapoptotic activity. Caffeine act as nutraceutical product, improves mental health. It contains antioxidants, vitamins, minerals and dietary supplements, by reducing the risk factor of several neurodegenerations including Alzheimer's disease, migraine, gallstone, cancer, Huntington's disease and sclerosis. This act as a stimulant and have capability to increase the effectiveness of certain pain killer. Beside positive affects, over-consumption of caffeine leads to negative impact: change in sleep pattern, hallucinations, high blood pressure, mineral loss and even heartburn. This chapter highlights pros and cons of caffeine consumption.

Effect of caffeine intake on self-reported and genetic prediction of osteoarthritis: an epidemiological study and Mendelian randomization analysis

Background

Osteoarthritis (OA) holds the distinction of being the most widespread musculoskeletal disorder. Any disruptions in the integrity of the articular cartilage can result in joint malfunction, discomfort, and impaired physical functioning. Increasing evidence indicates the negative impacts of caffeine intake on hyaline cartilage. The primary objective of this study was to delve deeper into understanding the potential link between the consumption of caffeine and the risk of developing OA.

Methods

In this study, we constructed logistic regression models to evaluate the correlation between caffeine consumption and the risk of osteoarthritis using data from the National Health and Nutrition Examination Survey. Following that, we utilized genome-wide association studies to conduct a Mendelian randomization (MR) analysis investigating the association between coffee consumption and the likelihood of developing knee OA. We employed various statistical methods, including inverse variance weighting (IVW), weighted median, weighted mode, simple mode, and MR-Egger regression, to ensure comprehensive analysis and robust conclusions. To evaluate heterogeneity and the potential impact of pleiotropy, we conducted several statistical tests, including Cochran's Q test, MR-Egger intercept test, MR Pleiotropy RESidual Sum and Outlier test (MR-PRESSO), and MR Steiger test.

Results

The weighted multivariate logistic regression analysis showed that the relationship between high caffeine intake (95-206 and ≥206 mg/day) and OA prevalence remained significantly high even after adjusting for covariates using the lowest caffeine intake (< 11 mg/day) as reference: Model 1-OR (95% Cl) = 1.365 (1.18-1.58) and 1.59 (1.38-1.83); Model 2-OR (95% Cl) = 1.21 (1.04-1.42) and 1.44 (1.23-1.68); and Model 3-OR (95% Cl) = 1.19 (1.01-1.40) and 1.30 (1.10-1.52), respectively (p < 0.05). The findings from the fixed effects inverse variance weighted (IVW) analysis revealed a statistically significant link between coffee intake and the likelihood of developing knee osteoarthritis: OR = 1.94; 95% confidence interval (Cl) =1.471-2.517; (p < 0.001). Consistent findings were obtained across various other methods, including MR-Egger regression, weighted median, weighted mode, and simple mode analyses.

Conclusion

Our study showed a positive correlation between OA prevalence and high caffeine intake (≥95 mg/day).

From bean to brain: Coffee, gray matter, and neuroprotection in neurological disorders spectrum

Coffee is a popular drink enjoyed around the world, and scientists are very interested in studying how it affects the human brain. This chapter looks at lots of different studies to understand how drinking coffee might change the brain and help protect it from neurodegenerative disorders especially like schizophrenia. With the help of available literature a link between the coffee mechanism and neurodegenerative disorders is established in this chapter. Researchers have found that drinking coffee can change the size of certain parts of the brain that control things like thinking and mood. Scientists also study how coffee's ingredients, especially caffeine, can change how the brain works. They think these changes could help protect the brain from diseases. This chapter focuses on how coffee might affect people with schizophrenia as hallucination is caused during and after excess consumption of caffeine. There's still a lot we don't know, but researchers are learning more by studying how different people's brains respond to coffee over time. Overall, this chapter shows that studying coffee and the brain could lead to new ways to help people with brain disorders. This study also draws ideas for future research and ways to help people stay healthy.

Coffee, antioxidants, and brain inflammation

Coffee is the most popular beverage in the world and, aside from tea and water, the most often consumed caffeine-containing beverage. Because of its high caffeine concentration, it is typically classified as a stimulant. There are other bioactive ingredients in coffee besides caffeine. The coffee beverage is a blend of several bioactive substances, including diterpenes (cafestol and kahweol), alkaloids (caffeine and trigonelline), and polyphenols (particularly chlorogenic acids in green beans and caffeic acid in roasted coffee beans). Caffeine has also been linked to additional beneficial benefits such as antioxidant and anti-inflammatory properties, which change cellular redox and inflammatory status in a dose-dependent manner. Pyrocatechol, a constituent of roasted coffee that is created when chlorogenic acid is thermally broken down, has anti-inflammatory properties as well. It is postulated that coffee consumption reduces neuroinflammation, which is intimately linked to the onset of neurodegenerative disorders like Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), and Huntington's disease (HD). This review provides an overview of the most recent studies regarding coffee's possible benefits in preventing brain inflammation and neurodegenerative disorders.

Flavan-3-ol monomers intake is associated with osteoarthritis risk in Americans over 40 years of age: results from the National Health and Nutritional Examination Survey database

Objectives: Osteoarthritis (OA) stands as the prevailing progressive musculoskeletal disease, serving as the primary cause of chronic pain and activity limitations among adults over 40. Flavan-3-ols, common polyphenolic compounds, are believed to harbor anti-inflammatory and anti-aging properties. This study explores the relationship between flavan-3-ol intake and osteoarthritis risk in individuals over the age of 40 in the US. Methods: This study included 7452 participants over the age of 40 from three cycles (2007-2008, 2009-2010, and 2017-2018) of the National Health and Nutrition Examination Survey. Information on OA history was obtained via home surveys. Information on flavan-3-ol monomers intake was obtained using a survey from the Food and Nutrient Database for Dietary Studies. We used a logistic regression model and restricted cubic spline to analyze the relationships between flavan-3-ol monomers and OA. Stratified analyses were also conducted in this study. Results: There were 1056 participants with OA and 6396 without OA. Compared to the first tertile (T1) group, the adjusted odds ratio with a 95% confidence interval (CI) of logistic regression model 2 for the flavan-3-ol T2 group was 1.296 (0.979-1.715) (p = 0.068), the OR for (-)-epigallocatechin was 1.292 (1.025-1.629) (p = 0.032), and the OR for (-)-epicatechin 3-gallate was 1.348 (1.013, 1.793) (p = 0.042). A dose-response curve indicated a non-linear association (p for non-linearity <0.05) between OA and total flavan-3-ol monomers (nadir point: 483.29 mg, 95% CI: 0.61-0.90). No interaction effects were found in the subgroup analysis. Conclusions: In individuals over 40 in the US, the average daily dietary intake of flavan-3-ol monomers manifests a J-shaped relationship with OA risk.

Can caffeine improve your performance? Psychophysiological effects - A systematic review

Introduction

Caffeine is a widely used ergogenic aid in society, which has made it a topic of interest due to its various benefits at cognitive, physiological, and sports levels, among others. This review aims to investigate the potential benefits of caffeine supplementation in psychophysiological performance through a structured search in the SportsDiscus/Scopus/MEDLINE and Web of Science databases (October 2022). This review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guideline, and the inclusion criteria were defined based on the PICOS model. Double-blind, randomized/semi-randomized crossover articles comparing caffeine intake with an identical placebo condition were included. Filters by age or gender of the participants were not applied. The initial search gave a result of 201 articles, which after eliminating duplicates and applying the inclusion and exclusion criteria, the final sample for this review was 8 studies. The review concluded that 3 (37.5 %) found favorable ergogenic effects, 4 (50 %) found partial effects, and 1 (12.5 %) found no effects of caffeine supplementation on variables related to psychophysiological performance. In general, both partial and negative results could be linked to insufficient doses to produce any change, likewise, habitual caffeine consumption is also a variable that could be attenuating its potential ergogenic effect. In conclusion, moderate doses of caffeine 3-6 mg/kg seem to be an effective strategy to improve the psychophysiological response in various contexts without generating detrimental effects on performance, as long as the intervention designs consider the variables that could condition its effect.

Ad libitum caffeine consumption, cognitive performance, and sleep in special forces soldiers during a 96-h combat exercise

Introduction

This observational study investigated the effects of sleep deprivation and ad libitum caffeine consumption on cognitive performance, risk behavior, and mood among 28 Israeli Special Forces (SF) soldiers (mean age: 20.57 ± 0.92 years) during a 96-hour combat exercise.

Methods

Actigraphy was used to monitor sleep and activity; cognitive function, risk-taking propensity, mood states, and self-reported sleepiness were assessed using the Psychomotor Vigilance Task (PVT), Evaluation of Risks Scale (EVAR), Profile of Mood States (POMS), Karolinska Sleepiness Scale (KSS); and caffeine consumption by questionnaire at 0, 50, and 96 hours. For analyses, participants were divided into Low (<400 mg) and High (≥400 mg) caffeine consumption groups.

Results

The soldiers hiked 108.5 ± 0.52 km and slept for 12.7 ± 0.5 h, with a notable transition from multiple short sleep epochs in the initial 50 hours to a consolidated 5-hour sleep period subsequently. In the High caffeine group, PVT reaction time was faster (p = 0.024) compared to the Low caffeine group, with fewer premature response errors (p = 0.026). However, this group showed increased risk-taking (p = 0.037), particularly reduced Self-Control (p = 0.010). No significant impact of ad libitum caffeine intake on mood was observed. However, degradation over the course of the exercise in both groups in mood states, including anger, fatigue, tension, and vigor, was noted (p < 0.05). KSS scores increased significantly at 50 and 96 h (p < 0.001).

Discussion

These results suggest that while caffeine enhances cognitive function, its ad libitum consumption did not consistently improve these measures in this cohort of SF soldiers. The study highlights the complex relationship between sleep deprivation and caffeine intake and their combined effects on soldiers' cognitive and behavioral functions, indicating a need for evidence-based caffeine use guidelines for using caffeine in military settings.

Evaluating the Reliability of Health Portals' Nutrition and Supplementation Advice for Pregnant Women: A Comprehensive Review

This article evaluates the reliability and consistency of nutrition- and supplementation-related advice for pregnant women provided by ten selected health-related Internet portals. The portals were chosen based on their perceived reliability and prominence in Google searches, with representation from both English and Polish language sources. The evaluation criteria included the adherence of the presented information to official recommendations and its evidence-based character based on specific items representing dietary aspects important in pregnancy. While the overall reliability was deemed acceptable, significant variations existed both among the portals and specific evaluated items. Notably, HealthLine, Medline Plus, and NCEZ emerged as the most evidence-based, while WebMD and Medycyna Praktyczna were identified as less reliable. Despite a number of issues, the analysed portals remain valuable sources of nutritional information for pregnant women, offering user-friendly accessibility superior to alternatives such as social media on the one hand and scientific articles on the other. Improved consistency and attention to detail, especially in relation to vitamin intake and supplementation, would improve the overall quality of health portals.

Increased Osteoblastic and Osteocytic in Vitro Cell Viability by Yerba Mate (Ilex paraguariensis)

BACKGROUND

Yerba mate (YM, Ilex paraguariensis) consumption beneficially affects the bones. However, whether YM components exert their effect on bone cells directly remains elusive.

METHODS

We evaluated how main YM components affect osteoblastic (MC3T3-E1) and osteocytic (MLO-Y4) cells in vitro when administered separately or in an aqueous extract. MC3T3-E1 and MLO-Y4 cells were exposed to three different experimental conditions: (1) Caffeine, chlorogenic acid, and their combinations; (2) Caffeine, rutin, and their combinations; (3) Aqueous YM extract.

RESULTS

All polyphenol and caffeine concentrations as well as that of their tested combinations significantly increased MC3T3-E1 cell viability from 16.6% to 34.8% compared to the control. In MLO-Y4 cells, the lowest rutin and the two highest caffeine concentrations significantly increased cell viability by 11.9, 14.9, and 13.7%, respectively. While rutin and caffeine combinations tended to increase MLO-Y4 cell viability, different chlorogenic acid and caffeine combinations did not affect it. Finally, the aqueous YM extract significantly increased MLO-Y4, MC3T3-E1, and differentiated MC3T3-E1 cell viability compared to the control without treatment.

CONCLUSIONS

YM components (rutin, chlorogenic acid, and caffeine) positively affected bone cells, mainly pre-osteoblast cells. Moreover, the aqueous YM extract significantly increased MLO-Y4, MC3T3-E1, and differentiated MC3T3-E1 cell viabilities indicating an additional relevant nutritional property of YM infusion. Further studies would be required to elucidate the underlying effector mechanism of YM on the bones and its relationship with previously described in vivo positive effects.

The Association Between Caffeine Consumption and Academic Success in Makkah Region, Saudi Arabia

BACKGROUND

 The consumption of caffeinated beverages has increased significantly, particularly, among young adults. They use caffeinated drinks for a variety of reasons. The most popular reason is to enhance mental alertness by improving brain function, wakefulness, and productivity. The high prevalence rate of caffeinated drinks among young adults may affect their academic performance level.

METHODOLOGY

 A descriptive cross-sectional study based on an electronic questionnaire via Google Forms, conducted in February 2022 after the biomedical ethics committee obtained the ethical approval at Umm Al-Qura University (UQU), College of Medicine, Makkah, Saudi Arabia, the sample size was 593 medical students in Makkah region.

RESULTS

 A total number of 593 medical students participated in this study, most of the medical students who participated (47.20%) had average GPA of 85%-95%. The largest number of medical students (45.30%) consume only one cup of caffeinated beverages per day. We reported no association between caffeinated beverages consumption and academic performance.

CONCLUSION

 Our study demonstrates that caffeinated beverages are a popular practice among medical college students. Majority of the medical students in Makkah region consume coffee as the most popular drink, while energy drinks are considered to be the least consumed drink, but energy drinks are easily affordable and available. Therefore, primary prevention of excessive consumption of caffeine is essential.

Polythiophene-wrapped Chitosan Nanofibrils with a Bouligand Structure toward Electrochemical Macroscopic Membranes

Exploring structural biomimicry is a great opportunity to replicate hierarchical frameworks inspired by nature in advanced functional materials for boosting new applications. In this work, we present the biomimetic integration of polythiophene into chitosan nanofibrils in a twisted Bouligand structure to afford free-standing macroscopic composite membranes with electrochemical functionality. By considering the integrity of the Bouligand structure in crab shells, we can produce large, free-standing chitosan nanofibril membranes with iridescent colors and flexible toughness. These unique structured features lead the chitosan membranes to host functional additives to mimic hierarchically layered composites. We used the iridescent chitosan nanofibrils as a photonic platform to investigate the host-guest combination between thiophene and chitosan through oxidative polymerization to fabricate homogeneous polythiophene-wrapped chitosan composites. This biomimetic incorporation fully retains the twisted Bouligand organization of nanofibrils in the polymerized assemblies, thus giving rise to free-standing macroscopic electrochemical membranes. Our further experiments are the modification of the biomimetic polythiophene-wrapped chitosan composites on a glassy carbon electrode to design a three-electrode system for simultaneous electrochemical detection of uric acid, xanthine, hypoxanthine, and caffeine at trace concentrations.

Caffeine Ameliorates Age-Related Hearing Loss by Downregulating the Inflammatory Pathway in Mice

OBJECTIVE

Age-related hearing loss (ARHL), also known as presbycusis, is a debilitating sensory impairment that affects the elderly population. There is currently no ideal treatment for ARHL. Long-term caffeine intake was reported to have anti-aging effects in many diseases. This study is to identify whether caffeine could ameliorate ARHL in mice and analyze its mechanism.

METHODS

Caffeine was administered in drinking water to C57BL/6J mice from the age of 3 months to 12 months. The body weight, food intake and water intake of the mice were monitored during the experiment. The metabolic indicators of serum were detected by ELISA. The function of the hearing system was evaluated by ABR and hematoxylin and eosin staining of the cochlea. Genes' expression were detected by Q-PCR, immunofluorescencee and Western blot.

RESULTS

The results showed that the ARHL mice exhibited impaired hearing and cochlear tissue compared with the young mice. However, the caffeine-treated ARHL mice showed improved hearing and cochlear tissue morphology. The expression of inflammation-related genes, such as TLR4, Myd88, NF-κB, and IL-1β, was significantly increased in the cochleae of ARHL mice compared with young mice but was down-regulated in the caffeine-treated cochleae.

CONCLUSIONS

Inflammation is involved in ARHL of mice, and long-term caffeine supplementation could ameliorate ARHL through the down-regulation of the TLR4/NF-κB inflammation pathway. Our findings provide a new idea for preventing ARHL and suggest new drug targets for ARHL treatment.

Prevalence of energy drink consumption world-wide: A systematic review and meta-analysis

BACKGROUND AND AIMS

The increasing market for energy drinks (EDs) in recent years, as well as the health risks caused by their consumption, prompt calls to estimate the prevalence of ED use among different countries. This systematic review and meta-analysis aimed to synthesize the prevalence of ED use in different continents and age groups.

METHOD

We searched two databases (i.e. PubMed and PsycInfo) on 31 March 2023 to identify studies reporting the prevalence of ED use. A total of 192 studies (196 distinct samples; n = 1 120 613; 53.37% males) from the United States, Europe, Asia, Oceania and Africa were included in the analysis. A random-effects model was applied to estimate the overall pooled prevalence at several time-periods. Subgroup analyses were performed to provide prevalence based on continent and age group. The quality of articles was assessed using Joana Brigg's Institute (JBI) critical appraisal checklist. Measurements included prevalence of ED use (i.e. life-time, past 12 months, past 30 days, past 7 days and daily use), continent and age group (i.e. children, adolescents, young adults and adults).

RESULTS

The life-time ED use world-wide-pooled prevalence was estimated to be 54.7% [95% confidence interval (CI) = 48.8-60.6; I2  = 99.80], 43.4% (95% CI = 36.1-50.6; I2  = 99.92) in the past 12 months, 32.3% (95% CI = 28.8-35.8; I2  = 99.82) in the past 30 days, 21.6% (95% CI = 18.7-24.5; I2  = 99.95) in the past 7 days and 8.82% (95% CI = 6.3-11.4; I2  = 99.95) daily ED use. Subgroups analyses showed significant differences in ED life-time use within age groups (P = 0.002) and continents (P = 0.035).

CONCLUSIONS

The world-wide prevalence of energy drink use appears to be high, particularly among adolescents and young adults.

Counteracting mental fatigue for athletes: a systematic review of the interventions

The deleterious effects of mental fatigue (MF) on athletes have been carefully studied in various sports, such as soccer, badminton, and swimming. Even though many researchers have sought ways to ameliorate the negative impact of MF, there is still a lack of studies that review the interventions used to counteract MF among athletes. This review aims to report the current evidence exploring the effects of interventions on MF and sport-specific performance, including sport-specific motor performance and perceptual-cognitive skills. Web of Science, Scopus, PubMed, and SPORTDicus (EBSCOhost) were combed through to find relevant publications. Additionally, the references and Google Scholar were searched for any grey literature. For the current review, we included only randomized controlled trials that involved athletes, a primary task to induce MF, interventions to counter MF with comparable protocols, and the outcomes of sport-specific motor performance and perceptual-cognitive skill. The selection criteria resulted in the inclusion of 10 articles. The manipulations of autonomous self-control exertion, person-fit, nature exposure, mindfulness, and transactional direct current stimulation showed that positive interventions counteract MF and improve sport-specific performance in different domains, including strength, speed, skill, stamina, and perceptual-cognitive skills. The selected interventions could significantly counteract MF and improve subsequent sport-specific performance. Moreover, self-regulation and attention resources showed the importance of the potential mechanisms behind the relevant interventions.

The caffeine dilemma: unraveling the intricate relationship between caffeine use disorder, caffeine withdrawal symptoms and mental well-being in adults

OBJECTIVE

This study aimed to explore the relationship between caffeine use disorder (CUD), caffeine withdrawal symptoms and the prevalence of depression, anxiety and stress (DASS) in adults.

DESIGN

The study utilised a cross-sectional design to assess the relationships between CUD, caffeine withdrawal symptoms and DASS.

SETTING

Participants' CUD was evaluated through the Caffeine Use Disorder Questionnaire (CUDQ), while the Depression Anxiety Stress Scale-21 (DASS-21) measured DASS levels. Caffeine withdrawal symptoms and total caffeine intake were calculated based on self-reported consumption of caffeine-rich products.

PARTICIPANTS

The study involved 618 participants with an average age of 27·8 (sd 7·8) years.

RESULTS

Participants consumed an average of 461·21 (sd 11·09) mg/d of caffeine, showing a positive correlation between CUD and total caffeine intake. The risk of CUD increased alongside levels of DASS. Individuals with caffeine withdrawal symptoms had higher CUDQ and DASS scores. A multiple linear regression model revealed significant associations between total caffeine intake (P < 0·001) and DASS-21 score (P < 0·001) with CUDQ score.

CONCLUSIONS

The study concluded that caffeine, while recognised for its potential health benefits, also exhibits properties that may lead to addiction. The development of caffeine use disorder and cessation of caffeine intake can increase DASS levels in adults, indicating the need for awareness and appropriate interventions in public health nutrition.

Impact of Caffeine Intake Strategies on Heart Rate Variability during Post-Exercise Recovery: A Systematic Review and Meta-Analysis

OBJECTIVES

The objective of this systematic review and meta-analysis is to evaluate the influence of caffeine (CAF) intake strategies, taking into account their form, timing, and dosage, on heart rate variability (HRV) indices in the post-exercise recovery period.

METHODS

The meta-analysis adhered to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines and is registered in the PROSPERO database (CRD42023425885). A comprehensive literature search was carried out across MEDLINE, Web of Science, LILACS, and SCOPUS, concluding in May 2023. We concentrated on randomized clinical trials comparing CAF supplementation effects to placebo on HRV indices post-exercise in active adults aged 18 and above. The primary endpoint was the assessment of HRV indices, measured both prior to and following exercise.

RESULTS

Of the 10 studies included, 7 were used for the meta-analysis, and all contributed to the systematic review. The research explored a variety of CAF strategies, spanning different forms (capsule, drink, gum), times (10, 45, 60 min) and doses (2.1 to 6.0 mg/kg). The outcomes revealed no substantial variations between the placebo and CAF conditions in terms of both the square root of the average of successive squared differences between adjacent RR intervals (RMSSD) (standardized mean difference (SMD) -0.03, 95% CI -0.265 to 0.197, p=0.77) and high frequency (HF) index (SMD -0.061, 95% CI -0.272 to 0.150, p=0.57). Furthermore, metaregression analysis, employing a fixed-effects model and accounting for the administered CAF doses, revealed no significant correlation between caffeine doses and HRV indices (p>0.05).

CONCLUSION

In conclusion, there is moderate-certainty evidence suggesting that different CAF intake strategies, encompassing aspects such as form, time, and dose, do not have a significant impact on HRV indices recovery post-exercise (i.e., vagal modulation).

Extrapolating the Coffee and Caffeine (1,3,7-Trimethylxanthine) Effects on Exercise and Metabolism-A Concise Review

The consumption of coffee and caffeine (1,3,7-trimethylxanthine) is part of many cultures worldwide. Their properties include serving as a neurostimulant aid, enhancing energy substrate levels, and improving general exercise performance. Both present therapeutic effects that can also be used to control chronic and metabolic diseases due to four mechanisms: adenosine receptor antagonism, increased catecholamine concentrations, a phosphodiesterase inhibitor, and a stimulator of calcium-release channels. Despite the individual genetic variabilities, distinct mechanisms have been demonstrated to improve physical performance, thermogenesis, lipolysis, insulin sensitivity, and hormonal modulation. Thus, coffee consumption and caffeine supplementation may enhance physical and mental performance and may improve metabolic variables, reducing oxidative stress, inflammation, and insulin resistance. Current data reveal vital aspects of coffee and caffeine consumption in specific populations, although further studies are needed to define clinical interventions with caffeine in obesity and chronic conditions.

Current therapeutic targets and multifaceted physiological impacts of caffeine

Caffeine, which shares consubstantial structural similarity with purine adenosine, has been demonstrated as a nonselective adenosine receptor antagonist for eliciting most of the biological functions at physiologically relevant dosages. Accumulating evidence supports caffeine's beneficial effects against different disorders, such as total cardiovascular diseases and type 2 diabetes. Conversely, paradoxical effects are also linked to caffeine ingestion in humans including hypertension-hypotension and tachycardia-bradycardia. These observations suggest the association of caffeine action with its ingested concentration and/or concurrent interaction with preferential molecular targets to direct explicit events in the human body. Thus, a coherent analysis of the functional targets of caffeine, relevant to normal physiology, and disease pathophysiology, is required to understand the pharmacology of caffeine. This review provides a broad overview of the experimentally validated targets of caffeine, particularly those of therapeutic interest, and the impacts of caffeine on organ-specific physiology and pathophysiology. Overall, the available empirical and epidemiological evidence supports the dose-dependent functional activities of caffeine and advocates for further studies to get insights into the caffeine-induced changes under specific conditions, such as asthma, DNA repair, and cancer, in view of its therapeutic applications.

Comparison of the Short-Term Effect of Coffee, Energy Drink, and Water on the Eyes in Young Healthy Subjects

PURPOSE

We aim to compare the short-term effects of energy drink (ED), coffee, and water on the eyes of young healthy male subjects.

MATERIALS AND METHODS

The right eyes of 30 healthy male subjects were included in this study. We measured the intraocular pressure (IOP), mean arterial pressure (MAP), retinal thickness (RT), choroidal thickness (CT), and retinal nerve fiber layer (RNFL) thickness using spectral domain optical coherence tomography (SD OCT). The measurements for RT and CT were taken at the fovea as well as 1,500 µm nasal and temporal to the fovea. The measurements of the subjects were performed on the first day before water consumption and at 30 minutes and 60 minutes following intake of 250 mL of water. Measurements were repeated at the same regime on the second day after drinking 250 mL of coffee containing an equal concentration of caffeine in ED (37.5 mg) and on the third day after drinking 250 mL of ED. Repeated measures one-way analysis of variance test was used for statistical analysis.

RESULTS

No significant difference was found for ocular perfusion pressure (OPP), MAP, RT, and IOP between the measurements taken on three consecutive days (p>0.05 for all). The CT values for the central, nasal, and temporal segments were significantly reduced in 0-30 and 0-60 minutes following coffee and ED intake (the range of p-value was <0.001-0.027).

CONCLUSIONS

Both coffee and ED intake caused acute and significant decreases in CT that persisted for one hour in young healthy male subjects. The impact of ED intake on CT was attributed mainly to its caffeine content.