The effects of intermittent fasting regimens in middle-age and older adults: Current state of evidence

Regulation of Metabolic Aging Through Adenosine Mono Phosphate-Activated Protein Kinase and Mammalian Target of Rapamycin: A Comparative Study of Intermittent Fasting Variations in Obese Young Women

Background/Objectives: Obesity accelerates metabolic aging through oxidative stress, inflammation, and mitochondrial dysfunction. AMP-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR) are nutrient-sensing pathways regulating metabolism. AMPK promotes energy metabolism and autophagy, while excessive mTOR activity contributes to aging. Intermittent fasting (IF), including time-restricted feeding (TRF)-limiting food intake to a 6 h window (18:6)-and alternate-day modified fasting (ADMF)-alternating 24 h fasting (≤25% daily caloric intake) with unrestricted feeding-may improve metabolic regulation. However, their effects on AMPK, mTOR, and metabolic age remain unclear. Methods: This quasi-experimental pre-test-post-test control group study compared the TRF and ADMF on metabolic age, AMPK, and mTOR in young obese women. Twenty-four participants (mean age: 21.29 ± 1.76 years; body fat: 36.92 ± 3.18%; BMI: 29.68 ± 3.70 kg/m2) were initially matched by BMI and assigned to Control, TRF, and ADMF groups. A total of 4 participants (1 Control, 3 ADMF) were excluded due to outlier values, yielding final group sizes: Control (n = 7), TRF (n = 8), and ADMF (n = 5). The intervention lasted 20 days. Results: A significant decrease in AMPK levels was observed in the ADMF group (p = 0.043), while changes in the TRF and Control groups were not significant. mTOR levels showed a decreasing trend but were not statistically significant. No significant changes were found in metabolic age. Conclusions: Twenty days of intermittent fasting intervention did not significantly affect AMPK, mTOR, or metabolic age in young obese women. TRF may more effectively enhance AMPK and reduce mTOR, while ADMF may better reduce metabolic age.

Time-restricted eating in early-stage Huntington's disease: A 12-week interventional clinical trial protocol

Huntington's disease (HD) is a devastating neurodegenerative disorder characterized by a variety of debilitating symptoms including abnormal motor control, cognitive impairment, and psychiatric disturbances. Despite significant efforts, efficacious treatments to alter the course of HD remain elusive, highlighting the need to explore new therapeutic strategies, including lifestyle changes that may delay the onset of symptoms and slow disease progression. Recent research indicates that time-restricted eating (TRE), a type of intermittent fasting where caloric intake is confined to a specific time window each day, may be beneficial in treating neurodegenerative diseases like HD. TRE has been found to enhance mitochondrial function, stimulate autophagy, lower oxidative stress, and improve cognitive performance. Although TRE has shown potential in HD animal models and non-HD populations, it has yet to be analyzed for safety, feasibility, and efficacy in persons with HD. Therefore, we propose a prospective interventional, open-label, single-arm, pilot study of 25 participants with late prodromal and early manifest HD to evaluate participant adherence to TRE diet - specifically, maintaining a 6-8-hour eating window every day for 12 weeks. Secondary measures will include pre- versus post-intervention assessment of body composition via bioelectrical impedance analysis, vital signs and safety labs, serum biomarkers of neurodegeneration, and standard HD behavioral, cognitive, and motor function clinical scales. Additional exploratory measures will evaluate sleep quality, physical activity, mood, dietary composition, and mitochondrial function. We expect that the diet will be safe, feasible, and may also improve biomarkers of disease progression in persons with HD. We anticipate this study will lay the foundation for future large-scale clinical trials to further evaluate the clinical efficacy of TRE in HD. This study has been registered on July 8, 2024 with ClinicalTrials.gov registration number NCT06490367 (https://clinicaltrials.gov/study/NCT06490367).

Challenges in Providing an Overview of Results of Intermittent Fasting Interventions on Diabetes Parameters. Comment on Silva et al. Effects of Intermittent Fasting on Regulation of Metabolic Homeostasis: A Systematic Review and Meta-Analysis in Health and Metabolic-Related Disorders. J. Clin. Med. 2023, 12, 3699

We hereby comment on the systematic review "Effects of Intermittent Fasting on Regulation of Metabolic Homeostasis: A Systematic Review and Meta-Analysis in Health and Metabolic-Related Disorders" by Silva et al [...].

Intermittent Fasting: Socio-Economic Profile of Spanish Citizens Who Practice It and the Influence of This Dietary Pattern on the Health and Lifestyle Habits of the Population

Intermittent fasting (IF) is a dietary approach that has gained popularity in recent years. More and more Spanish people are following this eating pattern, which consists of alternating periods of fasting with periods of food intake. Its benefits include improved metabolic and vascular health and weight loss.

OBJECTIVES

1. To study the prevalence of IF among the Spanish population. 2. To explore how demographic factors influence the choice to adopt this dietary approach.

METHODS

A descriptive cross-sectional study was conducted on the Spanish population using the NutSo-HH questionnaire, which was constructed, validated, and disseminated by the research team through a non-probabilistic snowball sampling approach, collecting socio-demographic data and nutritional, social and lifestyle habits of the population.

RESULTS AND CONCLUSIONS

A valid sample of 22,181 people participated, of whom 4.59% (n = 1018) said they practiced IF. The data show that more middle-aged men than women practice IF. In addition, individuals who follow IF methods are less likely to have no control over their food intake, are less scared to gain weight and have a higher body image, but no differences were found related to unhealthy food and nights out. There were also no significant differences in terms of the level of education, income, size of municipality, or region of residence. In conclusion, a person who practices IF seems to have adopted a healthier lifestyle and social habits.

A National Study Exploring the Association between Fasting Duration and Mortality among the Elderly

(1) Background: The benefits of weight management are widely recognized, and prolonged fasting duration has become a common method for weight control. The suitability of time-restricted eating (TRE) for elderly individuals remains controversial. This study aims to examine the correlation between fasting duration and mortality within a nationally representative cohort of elderly individuals in the United States. (2) Methods: Data were extracted from a prospective cohort study conducted as part of the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2018. Participants aged over 60 with complete data on dietary intake and mortality follow-up information were included. Fasting duration was assessed using two 24 h dietary recalls. All the participants were categorized into fasting duration quartiles. Mortality outcomes were ascertained through the National Death Index. Cox proportional hazards regression models were utilized to analyze the association between fasting duration and mortality. (3) Results: The final analysis included 10,561 elderly participants (mean age 69.89, 45.58% male). Individuals with the longest fasting duration (over 12.38 h) had a significantly higher risk of CVD mortality compared to those with a normal fasting duration (10.58-12.38 h). This elevated CVD mortality risk was particularly pronounced in males, individuals over 70 years old, and non-shift workers. A non-linear relationship was observed between fasting duration and all-cause mortality and CVD mortality. (4) Conclusions: Prolonged fasting periods are associated with a higher risk of CVD mortality in the elderly population, although this correlation is not evident for all-cause, cancer, or other-cause mortality. A fasting duration of 11.49 h correlates with the lowest mortality risk. Additionally, elderly individuals with the shortest fasting duration exhibit elevated hazard ratios for both cancer and other-cause mortality. As with any health intervention, clinicians should exercise caution when recommending a fasting regimen that is personalized to the health condition of people who are older. Further research through randomized controlled trials should be conducted to comprehensively investigate the impact of TRE on mortality.

Effects of Modified Ramadan Fasting on Mental Well-Being and Biomarkers in Healthy Adult Muslims - A Randomised Controlled Trial

BACKGROUND

Ramadan fasting has seen increased attention in research, often with inconsistent findings. This study aims to investigate whether dietary and lifestyle modifications during Ramadan can improve well-being and health in healthy adult Muslims.

METHOD

A randomised controlled trial with two parallel groups was conducted in an outpatient clinic of a university hospital in Essen, Germany, in 2016. Healthy adult Muslims (n = 114) aged 18-60 years were randomised to a modified fasting group; i.e., they received educational material prompting dietary and lifestyle modifications pre-Ramadan, and a control group who undertook Ramadan fasting as usual. Primary outcome was quality of life (WHO-5 Well-Being Index). Secondary outcomes included sleep quality, spirituality, and mindfulness (all self-report), body weight, body mass index, body fat, waist circumference, hip circumference, blood pressure, and heart rate, as well as blood serum biomarkers. Safety was examined via adverse events.

RESULTS

The modified fasting group reported significantly higher quality of life (WHO-5) compared to the control after Ramadan (MD 5.9; 95% CI, 0.02-11.8; p < 0.05). Group differences in favour of the modified fasting were also found for satisfaction with health (MD 5.9, 95% CI 0.19-11.67), ease of life (MD 4.1, 95% CI 0.38-7.80) and mindfulness (MD 7.6, 95% CI 2.68-12.52), reductions in weight (MD, - 0.9 kg; 95% CI - 1.39 to - 0.42), BMI (MD - 0.3 kg/m2, 95% CI - 0.50 to - 0.15), hip circumference (MD - 0.3 kg/m2, 95% CI - 0.50 to - 0.15), and diastolic blood pressure (MD - 2.8 mmHg, 95% CI - 5.15 to - 0.43). About 60% of participants reported adverse events, mostly headaches/migraines, dizziness/fatigue, common cold, and gastrointestinal symptoms, with no group differences. One serious non-related adverse event each occurred in both groups.

CONCLUSION

Pre-Ramadan dietary and lifestyle advice can lead to short-term improvements in mental and physical well-being of adult Muslims observing Ramadan. As such, this study demonstrates the potential benefits of culturally appropriate health interventions in a religious context.

TRIAL REGISTRATION

ClinicalTrials.gov (Identifier NCT02775175).

Dietary fasting and time-restricted eating in Huntington's disease: therapeutic potential and underlying mechanisms

Huntington's disease (HD) is a devastating neurodegenerative disorder caused by aggregation of the mutant huntingtin (mHTT) protein, resulting from a CAG repeat expansion in the huntingtin gene HTT. HD is characterized by a variety of debilitating symptoms including involuntary movements, cognitive impairment, and psychiatric disturbances. Despite considerable efforts, effective disease-modifying treatments for HD remain elusive, necessitating exploration of novel therapeutic approaches, including lifestyle modifications that could delay symptom onset and disease progression. Recent studies suggest that time-restricted eating (TRE), a form of intermittent fasting involving daily caloric intake within a limited time window, may hold promise in the treatment of neurodegenerative diseases, including HD. TRE has been shown to improve mitochondrial function, upregulate autophagy, reduce oxidative stress, regulate the sleep-wake cycle, and enhance cognitive function. In this review, we explore the potential therapeutic role of TRE in HD, focusing on its underlying physiological mechanisms. We discuss how TRE might enhance the clearance of mHTT, recover striatal brain-derived neurotrophic factor levels, improve mitochondrial function and stress-response pathways, and synchronize circadian rhythm activity. Understanding these mechanisms is critical for the development of targeted lifestyle interventions to mitigate HD pathology and improve patient outcomes. While the potential benefits of TRE in HD animal models are encouraging, future comprehensive clinical trials will be necessary to evaluate its safety, feasibility, and efficacy in persons with HD.

Does time-restricted eating add benefits to calorie restriction? A systematic review

OBJECTIVE

A growing body of evidence has supported the health benefits of extended daily fasting, known as time-restricted eating (TRE); however, whether the addition of TRE enhances the known benefits of calorie restriction (CR) remains unclear.

METHODS

PubMed, Scopus, the Cochrane Library, and Google Scholar were searched through April 2023. This systematic review includes randomized controlled trials (RCTs) that compared CR + TRE with CR alone in energy-matched conditions of at least 8 weeks in duration that assessed changes in body weight and cardiometabolic disease risk factors in adults with overweight and/or obesity.

RESULTS

Seven studies were identified (n = 579). Two studies reported greater weight loss and reductions in diastolic blood pressure with CR + TRE compared with CR alone after 8 to 14 weeks, whereas one study reported greater improvements in triglycerides and glucose tolerance with CR + TRE (3 days/week) compared with CR alone following 26 weeks. One study reported significant increases in homeostatic model assessment of insulin resistance (HOMA-IR) levels with CR + TRE versus CR alone after 8 weeks. There were no statistically significant differences in any other outcome variable between the two interventions.

CONCLUSIONS

The addition of TRE to CR regimens resulted in greater weight loss and improvements in cardiometabolic risk factors in some studies; however, the majority of studies did not find additional benefits.

Ancestry Specific Polygenic Risk Score, Dietary Patterns, Physical Activity, and Cardiovascular Disease

It is unknown whether the impact of high diet quality and physical activity depends on the level of polygenic risk score (PRS) in different ancestries. Our cross-sectional study utilized de-identified data from 1987-2010 for self-reported European Americans (n = 6575) and African Americans (n = 1606). The high-risk PRS increased ASCVD risk by 59% (Risk Ratio (RR) = 1.59; 95% Confidence Interval:1.16-2.17) in the highest tertile for African Americans and by 15% (RR = 1.15; 1.13-1.30) and 18% (RR = 1.18; 1.04-1.35) in the second and highest tertiles compared to the lowest tertile in European Americans. Within the highest PRS tertiles, high physical activity-diet combinations (Dietary Approaches to Stop High Blood Pressure (DASH), Mediterranean, or Southern) reduced ASCVD risks by 9% (RR = 0.91; 0.85-0.96) to 15% (RR = 0.85; 0.80-0.90) in European Americans; and by 13% (RR = 0.87; 0.78-0.97) and 18% (RR = 0.82; 0.72-0.95) for DASH and Mediterranean diets, respectively, in African Americans. Top molecular pathways included fructose metabolism and catabolism linked to obesity, insulin resistance, and type 2 diabetes. Additional molecular pathways for African Americans were Vitamin D linked to depression and aging acceleration and death signaling associated with cancer. Effects of high diet quality and high physical activity can counterbalance the influences of genetically high-risk PRSs on ASCVD risk, especially in African Americans.

Intermittent fasting and Alzheimer's disease-Targeting ketone bodies as a potential strategy for brain energy rescue

Alzheimer's disease (AD) lacks effective clinical treatments. As the disease progresses, the cerebral glucose hypometabolism that appears in the preclinical phase of AD gradually worsens, leading to increasingly severe brain energy disorders. This review analyzes the brain energy deficit in AD and its etiology, brain energy rescue strategies based on ketone intervention, the effects and mechanisms of IF, the differences in efficacy between IF and ketogenic diet and the duality of IF. The evidence suggests that brain energy deficits lead to the development and progression of AD pathology. IF, which improves brain energy impairments by promoting ketone metabolism, thus has good therapeutic potential for AD.

Ancestry Specific Polygenic Risk Score, Dietary Patterns, Physical Activity, and Cardiovascular Disease

Background

It is unknown whether the impact of high diet-quality and physical activity (PA) depends on the level of polygenic risk score (PRS) in different ancestries.

Objective

Determine the associations and interactions between high-risk PRSs, dietary patterns, and high PA with atherosclerotic cardiovascular disease (ASCVD) in European Americans (EAs) and African Americans (AAs). Another aim determined the molecular pathways of PRS-mapped genes and their relationships with dietary intake.

Methods

Cross-sectional analyses utilized de-identified data from 1987-2010 from 7-National Heart, Lung, and Blood Institute Candidate Gene Association Resource studies from the Database of Genotypes and Phenotypes studies for EAs (n=6,575) and AAs (n=1,606).

Results

The high-risk PRS increased ASCVD risk by 59% (Risk Ratio=1.59;95% Confidence Interval:1.16-2.17) in the highest tertile for AAs and by 15% (RR=1.15;1.13-1.30) and 18% (RR=1.18;1.04-1.35) in the second and highest tertiles compared to the lowest tertile in EAs. Within the highest PRS tertiles, high PA-diet combinations (Dietary Approaches to Stop High Blood Pressure (DASH), or Mediterranean, or Southern) reduced ASCVD risks by 9% (RR=0.91;0.85-0.96) to 15% (RR=0.85;0.80-0.90) in EAs; and by 13% (RR=0.87;0.78-0.97) and 18% (RR=0.82;0.72-0.95) for the DASH and Mediterranean diets, respectively in AAs. Top molecular pathways included fructose metabolism and catabolism linked to obesity, insulin resistance, and type 2 diabetes in both ancestries. Additional molecular pathways for AAs were Vitamin D linked to depression and aging acceleration; and death signaling associated with cancer.

Conclusions

Effects of high diet-quality and high PA can counterbalance the influences of genetically high-risk PRSs on ASCVD risk, especially in AAs.

Intestinal microbiota: a new perspective on delaying aging?

The global aging situation is severe, and the medical pressures associated with aging issues should not be underestimated. The need and feasibility of studying aging and intervening in aging have been confirmed. Aging is a complex natural physiological progression, which involves the irreversible deterioration of body cells, tissues, and organs with age, leading to enhanced risk of disease and ultimately death. The intestinal microbiota has a significant role in sustaining host dynamic balance, and the study of bidirectional communication networks such as the brain-gut axis provides important directions for human disease research. Moreover, the intestinal microbiota is intimately linked to aging. This review describes the intestinal microbiota changes in human aging and analyzes the causal controversy between gut microbiota changes and aging, which are believed to be mutually causal, mutually reinforcing, and inextricably linked. Finally, from an anti-aging perspective, this study summarizes how to achieve delayed aging by targeting the intestinal microbiota. Accordingly, the study aims to provide guidance for further research on the intestinal microbiota and aging.

Time-Restricted Eating and Its Metabolic Benefits

Newer management strategies are being evaluated to treat obesity, which continues to increase worldwide. After 12 h of fasting, the body switches from glucose to fat metabolism, regulating protein synthesis and autophagy. These cellular responses are central to the metabolic benefits of time-restricted eating (TRE), independent of calorie restriction and weight loss, and they have heightened interest in TRE regimens. Controversy remains, however, regarding the benefits of TRE regimens. We reviewed the current literature and concluded that TRE is equivalent to calorie restriction for weight loss and has positive effects for patients with diseases such as nonalcoholic fatty liver disease, cancer, and cardiovascular disease.

Intermittent Fasting Sustainably Improves Glucose Tolerance in Normal Weight Male Mice Through Histone Hyperacetylation

To explore the mechanism by which intermittent fasting (IF) exerts prolonged effects after discontinuation, we examined mice that had been subjected to 4 cycles of fasting for 72 hours and ad libitum feeding for 96 hours per week (72hIF), followed by 4 weeks of ad libitum feeding, focusing on expression of genes for lipid metabolism in the skeletal muscle and histone acetylation in the promoter region. The 72hIF regimen resulted in metabolic remodeling, characterized by enhanced lipid utilization and mitochondrial activation in the muscle. This long-term IF (72hIF) caused stronger metabolic effects than alternate day fasting (24hIF) wherein fasting and refeeding are repeated every 24 hours. Upregulation of lipid oxidation genes and an increase in oxygen utilization were sustained even at 4 weeks after discontinuation of 72hIF, associated with histone hyperacetylation of the promoter region of uncoupling protein 3 (Ucp3) and carnitine palmitoyl transferase 1b (Cpt1b) genes. An increase in leucine owing to fasting-induced muscle degradation was suggested to lead to the histone acetylation. These findings support the previously unappreciated notion that sustainable promotion of histone acetylation in lipid oxidation genes of the muscle and adipose tissues during and after IF may contribute to sustained metabolic effects of IF.

Comparison of the effects of six-week time-restricted eating on weight loss, body composition, and visceral fat in overweight older men and women

The aim of this study was to determine the effectiveness of a six-week time-restricted eating (TRE) intervention in reducing body weight, fat loss, and visceral fat in overweight, older adult men and women (age range = 65-74 years). Another objective was to determine the feasibility of widespread use of TRE in older women and men. The study randomly assigned 116 healthy, non-smoking participants to one of two conditions: TRE or educational control participants. Participants in the TRE group were instructed to not consume calorie containing beverages or food for 16 h per day, from 8:00 pm to 12:00 pm. Participants in the control group were instructed to follow a meal plan based on their previous habits. The changes in body weight and body composition were determined using a SECA mBCA 515 analyzer. The six-week TRE intervention resulted in a significant decrease in body weight in both men and women (-1.8 kg and-1.3 kg, respectively; p = 0.03). In men, a significant decrease in visceral fat mass (-0.54 l; p ≤ 0.001) and waist circumference (-2.9 cm; p ≤ 0.015) was observed. No significant changes in either visceral fat or waist circumference were observed in women. Additionally, no change in skeletal muscle mass was observed in either the control or TRE group. More than 99 % of female and 98 % of male participants were able to adhere to the prescribed time-restricted eating (16/8) plan, suggesting that this dietary approach could have beneficial effects on the body composition of overweight older men and may also reduce body weight in overweight, older women.

The Effects of Isocaloric Intermittent Fasting vs Daily Caloric Restriction on Weight Loss and Metabolic Risk Factors for Noncommunicable Chronic Diseases: A Systematic Review of Randomized Controlled or Comparative Trials

BACKGROUND

Intermittent fasting (IF) has gained favor as an alternative regimen to daily caloric restriction (DCR). Therefore, there is a need for systematic reviews of randomized controlled/comparison trials examining the effects of isocaloric IF vs DCR on metabolic risk factors for noncommunicable chronic diseases.

OBJECTIVE

To systematically investigate the effects of isocaloric IF vs DCR on metabolic risk factors for noncommunicable chronic diseases in adults with overweight and obesity.

METHODS

Five online databases (PubMed, Scopus, Web of Science, Cochrane Central Register of Controlled Trials, and Google Scholar) were searched for articles published from January 2000 through April 2022. The updated Cochrane Risk of Bias Assessment tool for randomized controlled/comparison trials was used to assess risk of bias in the included studies. This review includes randomized controlled/comparison trials with matched energy intakes (isocaloric) between IF and DCR among adults with overweight and obesity with ≥8-week durations, that assessed risk factors related to obesity and for diabetes, cardiovascular diseases, and cancers.

RESULTS

Thirteen randomized controlled/comparison trials with matched energy intakes (isocaloric) between IF and DCR were identified. The effects of IF on weight loss and metabolic risk markers of diabetes, cardiovascular diseases, and cancers were varied but generally comparable with DCR. IF (4:3 and 5:2 diets) was superior to DCR for improving insulin sensitivity in two studies. Reductions in body fat were significantly greater with IF (5:2 diet and time-restricted eating) than DCR in two studies of isocaloric diets.

CONCLUSIONS

With matched energy intakes, IF interventions produced similar beneficial effects for weight loss and chronic disease risk factors compared with DCR. Very limited evidence suggests that IF may be more effective vs DCR for fat loss and insulin sensitivity, but conclusions cannot be drawn based on the current evidence. Future clinical studies with larger populations and longer durations are needed for further elucidation of any potential effects of IF regimens for prevention of noncommunicable chronic diseases.

Intermittent Fasting-Short- and Long-Term Quality of Life, Fatigue, and Safety in Healthy Volunteers: A Prospective, Clinical Trial

Background: Intermittent fasting (IF) is defined as an eating pattern without calorie restrictions, alternating between periods of fasting and eating. In the past decades IF has not only become a popular weight-reducing diet but is thought to improve Quality of Life (QoL) and fatigue. However, very little evidence exists for the general population. Thus, we aimed to assess the impact of a 16-h fasting period per day over a three-month study period on QoL and especially fatigue in healthy people. Methods: We conducted a prospective cohort study including healthy subjects. All participants fasted 16 h for at least five days a week while maintaining their normal lifestyle. In the study, we analysed blood samples as well as QoL through standardized questionnaires (WHO-5 questionnaire, Short Form Health 36). Furthermore, we measured the degree of fatigue with the Fatigue Assessment Scale (FAS) and Fatigue Severity Scale (FSS) as well as compliance, activity records, and weight alterations. All endpoints were evaluated at baseline, after two weeks, four weeks, and three months of IF. Results: A total of 30 participants fasted for the entire study period. The results of the WHO-5 questionnaire (15.6 ± 4.6 vs. 18 ± 3.6, p < 0.0019) demonstrated a significant increase in QoL. For long-term QoL six out of eight domains measured by the Short Form Health 36 (SF-36) significantly improved (e.g., physical health: 92.3 ± 11.6 vs. 96.5 ± 6.3, p = 0.015; mental health: 75.5 ± 12.0 vs. 81.7 ± 9.0; p < 0.001 and body pain: 74.1 ± 31.8 vs. 89.5 ± 14.9; p = 0.008) after three months. Fatigue significantly decreased from 10.3 ± 3.2 to 8.4 ± 2.5; p = 0.002 for mental fatigue and from 12.6 ± 3.8 to 10.7 ± 3.3; p = 0.002 measured by the FAS. The mean FSS-Score at baseline was 3.5 ± 1.2 compared to 2.9 ± 1.1 (scale 1−7) after three months (p < 0.001). Notably, the proliferation marker IGF-1 was significantly reduced. No clinically significant changes in laboratory parameters were observed that would have endangered a participant’s safety. Conclusions: IF according to the 16:8 regime over a fasting period of three months significantly improved several aspects of the QoL and decreased fatigue in healthy people, while maintaining a good safety profile. The practicability of this diet was also demonstrated for shift workers and people with a high percentage of active labour. Apart from the improvement in QoL and fatigue, the significant reduction in IGF-1, which can act as an accelerator of tumour development and progression, might be an indicator of the potential benefits of IF for patients with cancer.

Therapeutic Fasting: Are Patients Aged 65 and Over Ready?

While being the main potential beneficiaries of therapeutic fasting’s health benefits, the elderly are frequently thought of as being too fragile to fast. The main objective of our survey was to review the knowledge, practices, and acceptability of therapeutic fasting in subjects aged 65 years and over. From September 2020 to March 2021, an online questionnaire was sent to subjects aged 65 and over, using the mailing list of local organizations working in the field of aging. The mean age of the 290 respondents was 73.8 ± 6.5 years, 75.2% were women and 54.1% had higher education. Among the respondents, 51.7% had already fasted and 80.7% deemed therapeutic fasting interesting, 83.1% would be willing to fast if it was proven beneficial for their health, and 77.2% if it was proven to decrease the burden of chronic diseases. Subjects aged 65 to 74 years considered themselves as having the greatest physical and motivational abilities to perform therapeutic fasting. People aged 65 years, or more, are interested in therapeutic fasting and a large majority would be ready to fast if such practice was proven beneficial. These results pave the way for future clinical trials evaluating therapeutic fasting in elderly subjects.