The effects of cinnamon supplementation on blood lipid concentrations: A systematic review and meta-analysis

A historical, evidence-based, and narrative review on commonly used dietary supplements in lipid-lowering

Dietary supplements augment the nutritional value of everyday food intake and originate from the historical practices of ancient Egyptian (Ebers papyrus), Chinese (Pen Ts'ao by Shen Nung), Indian (Ayurveda), Greek (Hippocrates), and Arabic herbalists. In modern-day medicine, the use of dietary supplements continues to increase in popularity with greater than 50% of the US population reporting taking supplements. To further compound this trend, many patients believe that dietary supplements are equally or more effective than evidence-based therapies for lipoprotein and lipid-lowering. Supplements such as red yeast rice, omega-3 fatty acids, garlic, cinnamon, plant sterols, and turmeric are marketed to and believed by consumers to promote "cholesterol health." However, these supplements are not subjected to the same manufacturing scrutiny by the Food and Drug Administration as pharmaceutical drugs and as such, the exact contents and level of ingredients in each of these may vary. Furthermore, supplements do not have to demonstrate efficacy or safety before being marketed. The holistic approach to lowering atherosclerotic cardiovascular disease risk makes dietary supplements an attractive option to many patients; however, their use should not come at the expense of established therapies with proven benefits. In this narrative review, we provide a historical and evidence-based approach to the use of some dietary supplements in lipoprotein and lipid-lowering and provide a framework for managing patient expectations.

A Mechanistic Review on Therapeutic Potential of Medicinal Plants and their Pharmacologically Active Molecules for Targeting Metabolic Syndrome

Metabolic syndrome (MetS) therapy with phytochemicals is an emerging field of study with therapeutic potential. Obesity, insulin resistance, high blood pressure, and abnormal lipid profiles are all components of metabolic syndrome, which is a major public health concern across the world. New research highlights the promise of phytochemicals found in foods, including fruits, vegetables, herbs, and spices, as a sustainable and innovative method of treating this illness. Anti-inflammatory, antioxidant, and insulin-sensitizing qualities are just a few of the many positive impacts shown by bioactive substances. Collectively, they alleviate the hallmark symptoms of metabolic syndrome by modulating critical metabolic pathways, boosting insulin sensitivity, decreasing oxidative stress, and calming chronic low-grade inflammation. In addition, phytochemicals provide a multimodal strategy by targeting not only adipose tissue but also the liver, skeletal muscle, and vascular endothelium, all of which have a role in the pathogenesis of MetS. Increasing evidence suggests that these natural chemicals may be useful in controlling metabolic syndrome as a complementary treatment to standard medication or lifestyle changes. This review article emphasizes the therapeutic potential of phytochemicals, illuminating their varied modes of action and their ability to alleviate the interconnected causes of metabolic syndrome. Phytochemical-based interventions show promise as a novel and sustainable approach to combating the rising global burden of metabolic syndrome, with the ultimate goal of bettering public health and quality of life.

A Scoping Review of the Clinical Evidence for the Health Benefits of Culinary Doses of Herbs and Spices for the Prevention and Treatment of Metabolic Syndrome

Metabolic syndrome (MetS) is a growing global health problem. Evidence suggests that diets rich in phytochemical-containing herbs and spices can contribute to reducing the risk of chronic diseases. This review assesses the scope of evidence supporting the use of herbs and spices in the diet for the prevention or treatment of MetS and its associated health conditions. A search of the PubMed, Scopus and Google Scholar databases was carried out to assess the available clinical evidence for culinary doses of commonly used herbs and spices. Trials that were measuring health factors related to metabolic disorders in healthy individuals, or the health of individuals with MetS or associated diseases, were included. Out of a total of 1738 papers identified, there were 142 relevant studies on black pepper, chilli, cardamom, cinnamon, coriander, cumin, fennel, fenugreek, garlic, ginger, nigella seed, rosemary, sage and turmeric. No relevant research was found for cloves, mint, oregano, parsley or thyme. Cinnamon, fenugreek and ginger were the herbs/spices with the most published trials on them and that showed promise for glycaemic control. Cardamom appears to have potential to reduce inflammatory markers, and cinnamon, ginger and turmeric to reduce blood lipids. Patients with type 2 diabetes were the population most likely to be included in studies, but the preventative benefits of herbs/spices in healthy populations were also investigated, particularly for chilli, ginger and cinnamon. There is evidence for the beneficial effect of culinary doses of many common herbs/spices in the prevention and treatment of MetS and associated disorders.

The effect of cinnamon consumption on lipid profile, oxidative stress, and inflammation biomarkers in adults: An umbrella meta-analysis of randomized controlled trials

AIMS

Cinnamon is a polyphenol-rich spice that has beneficial effects on markers of cardio metabolic health such as lipid profile, oxidative stress, and inflammation. Despite the accumulating evidence from meta-analyses on the effects of cinnamon on these markers, their findings are controversial. Thus, this umbrella meta-analysis was performed to evaluate the present evidence and provide a conclusive clarification.

DATA SYNTHESIS

We searched the following international databases from inception to January 2022: PubMed, Scopus, Web of Science and Embase, and Google Scholar. Our findings of eleven meta-analyses showed that cinnamon consumption can significantly improve total cholesterol (TC) (WMD = -1.01 mg/dL; 95% CI: -2.02, -0.00, p = 0.049), low-density lipoprotein-cholesterol (LDL-C) (WMD = -0.82 mg/dL; 95% CI: -1.57, -0.07, p = 0.032), and high-density lipoprotein-cholesterol (HDL-C) (WMD = 0.47 mg/dL; 95% CI: 0.17, 0.77, p = 0.002) levels but not triglyceride (TG) levels (WMD = -0.13 mg/dL; 95% CI: -0.58, 0.32, p = 0.570). Our results did not show any significant effect of cinnamon on malondialdehyde (MDA) levels (WMD = -0.47; 95% CI: -0.99, 0.05, p = 0.078) and C-reactive protein (CRP) levels (WMD = -1.33; 95% CI: -2.66, 0.00, p = 0.051) but there was enhanced total antioxidant capacity (TAC) in patients with type 2 diabetes (T2DM) and polycystic ovary syndrome (PCOS) (WMD = 0.34; 95% CI: 0.04, 0.64, p = 0.026) and increased levels of interleukin-6 (WMD = -1.48; 95% CI: -2.96, -0.01, p = 0.049).

CONCLUSIONS

Our results support the usefulness of cinnamon intake in modulating an imbalanced lipid profile in some metabolic disorders, particularly PCOS, as well as in improving TAC and interleukin-6. The review protocol was registered on PROSPERO as CRD42022358827.

Unravelling Effects of Rosemary (Rosmarinus officinalis L.) Extract on Hepatic Fat Accumulation and Plasma Lipid Profile in Rats Fed a High-Fat Western-Style Diet

The objective of the study was to investigate the preventive effect on obesity-related conditions of rosemary (Rosmarinus officinalis L.) extract (RE) in young, healthy rats fed a high-fat Western-style diet to complement the existing knowledge gap concerning the anti-obesity effects of RE in vivo. Sprague Dawley rats (71.3 ± 0.46 g) were fed a high-fat Western-style diet (WD) or WD containing either 1 g/kg feed or 4 g/kg feed RE for six weeks. A group fed standard chow served as a negative control. The treatments did not affect body weight; however, the liver fat percentage was reduced in rats fed RE, and NMR analyses of liver tissue indicated that total cholesterol and triglycerides in the liver were reduced. In plasma, HDL cholesterol was increased while triglycerides were decreased. Rats fed high RE had significantly increased fasting plasma concentrations of Glucagon-like peptide-1 (GLP-1). Proteomics analyses of liver tissue showed that RE increased enzymes involved in fatty acid oxidation, possibly associated with the higher fasting GLP-1 levels, which may explain the improvement of the overall lipid profile and hepatic fat accumulation. Furthermore, high levels of succinic acid in the cecal content of RE-treated animals suggested a modulation of the microbiota composition. In conclusion, our results suggest that RE may alleviate the effects of consuming a high-fat diet through increased GLP-1 secretion and changes in microbiota composition.

Supplements for Lipid Lowering: What Does the Evidence Show?

PURPOSE

In this review, the regulation, proposed hypolipidemic mechanism, and efficacy of common dietary supplements (DSs) marketed for cardiovascular health are discussed.

RECENT FINDINGS

Data demonstrate modest but inconsistent lipid-lowering effects with common DSs such as probiotics, soluble fibers, plant sterols, green tea, berberine, guggul, niacin, and garlic. Furthermore, data is limited regarding turmeric, hawthorn, and cinnamon. Red yeast rice has shown to be a beneficial DS, but its safety and efficacy are dependent upon its production quality and monacolin K content, respectively. Finally, soy proteins and omega-3 fatty acid-rich foods can have significant health benefits if used to displace other animal products as part of a healthier diet. Despite the rising use of DSs, data demonstrate unpredictable results. Patients should be educated on the difference between these DSs and evidence-based lipid-lowering medications proven to improve cardiovascular outcomes.

Antiobesity effects of onion (Allium cepa) in subjects with obesity: Systematic review and meta-analysis

Onions are rich in bioactive compounds and have been found to prevent various chronic diseases, including obesity. We performed a systematic review and meta-analysis to investigate the antiobesity effect of onions. Studies were identified in PubMed/MEDLINE, Embase, Web of Science, and CENTRAL focusing on clinical trials evaluating the antiobesity effects of onion in obese subjects. The risk of bias in the studies was evaluated using Cochrane's Risk of Bias tool. The effect of onions was analyzed using data from the selected studies, and the results were indicated by weighted mean difference with 95% CI. The I 2 static test was used to examine heterogeneity between the studies. A total of 38 studies were reviewed, of which five clinical trials meeting the criteria were selected. As investigational products, onion peels were used in four studies and onions were used in one study. Following systematic review, it was determined that the risk of bias was generally low, and body weight, BMI, waist circumference, and triglyceride levels were significantly reduced in the onion groups compared to the placebo. In conclusion, onion intake had an antiobesity effect by reducing body weight and body fat, and this effect was particularly pronounced with onion peel.

Exploring the Impact of Nutrition on Non-Alcoholic Fatty Liver Disease Management: Unveiling the Roles of Various Foods, Food Components, and Compounds

There is a need to introduce standardized treatment options for non-alcoholic fatty liver disease (NAFLD) due to its global prevalence and the complications of this disease. Many studies have revealed that food-derived substances may be beneficial in dealing with this disease. Therefore, this review aims to evaluate the recently published studies on the food-derived treatment options for NAFLD. A comprehensive search of the PubMed database using keywords such as "NAFLD", "nutrition", "food", "derived", "therapy", and "guidelines" yielded 219 relevant papers for our analysis, published from 2004 to 2023. The results show the significant benefits of food-derived treatment in NAFLD therapy, including improvements in liver histology, hepatic fat amounts, anthropometric measures, lipid profile, and other metabolic measures. The availability of the substances discussed makes them a significant adjuvant in the treatment of this disease. The usefulness of Viusid as additional therapy to diet and physical activity should be emphasized due to improvements in liver histology; however, many other substances lead to a decrease in liver fat amounts including, e.g., berberine or omega-3 fatty acids. In addition, the synbiotic Protexin seems to be useful in terms of NAFLD treatment, especially because it is effective in both obese and lean subjects. Based on the latest research results, we suggest revising the therapeutic recommendations for patients suffering from NAFLD.

Comparative Effects of Low-Dose Rosuvastatin, Placebo, and Dietary Supplements on Lipids and Inflammatory Biomarkers

BACKGROUND

Supplements are commonly used by individuals with indications for lipid-lowering therapy, but evidence of their effectiveness to lower low-density lipoprotein cholesterol (LDL-C) is lacking, particularly when compared with statins.

OBJECTIVES

The trial objective was to compare the efficacy of a low-dose statin with placebo and 6 common supplements in impacting lipid and inflammatory biomarkers.

METHODS

This was a single-center, prospective, randomized, single-blind clinical trial among adults with no history of atherosclerotic cardiovascular disease (ASCVD), an LDL-C of 70 to 189 mg/dL, and an increased 10-year risk of ASCVD. Participants were randomized to rosuvastatin 5 mg daily, placebo, fish oil, cinnamon, garlic, turmeric, plant sterols, or red yeast rice. The primary endpoint was the percent change in LDL-C from baseline for rosuvastatin 5 mg daily compared with placebo and each supplement after 28 days. The primary endpoint was evaluated in a hierarchical fashion with rosuvastatin first compared with placebo, then each supplement in a prespecified order using analysis of covariance.

RESULTS

A total of 190 participants completed the study. The percent LDL-C reduction with rosuvastatin was greater than all supplements and placebo (P < 0.001). The difference in LDL-C reduction with rosuvastatin compared with placebo was -35.2% (95% CI: -41.3% to -29.1%; P < 0.001). None of the dietary supplements demonstrated a significant decrease in LDL-C compared with placebo. Adverse event rates were similar across study groups.

CONCLUSIONS

Among individuals with increased 10-year risk for ASCVD, rosuvastatin 5 mg daily lowered LDL-C significantly more than placebo, fish oil, cinnamon, garlic, turmeric, plant sterols, and red yeast rice. (Supplements, Placebo, or Rosuvastatin Study [SPORT]; NCT04846231).

Cinnamon: an aromatic condiment applicable to chronic kidney disease

Cinnamon, a member of the Lauraceae family, has been widely used as a spice and traditional herbal medicine for centuries and has shown beneficial effects in cardiovascular disease, obesity, and diabetes. However, its effectiveness as a therapeutic intervention for chronic kidney disease (CKD) remains unproven. The bioactive compounds within cinnamon, such as cinnamaldehyde, cinnamic acid, and cinnamate, can mitigate oxidative stress, inflammation, hyperglycemia, gut dysbiosis, and dyslipidemia, which are common complications in patients with CKD. In this narrative review, we assess the mechanisms by which cinnamon may alleviate complications observed in CKD and the possible role of this spice as an additional nutritional strategy for this patient group.

Kidney and lipids: novel potential therapeutic targets for dyslipidemia in kidney disease?

INTRODUCTION

Altered lipid distribution and metabolism may lead to the development and/or progression of chronic kidney disease (CKD). Dyslipidemia is a major risk factor for CKD and increases the risk of cardiovascular events and mortality. Therefore, lipid-lowering treatments may decrease cardiovascular risk and prevent death.

AREAS COVERED

Key players involved in regulating lipid accumulation in the kidney; contribution of lipids to CKD progression, lipotoxicity, and mitochondrial dysfunction in kidney disease; recent therapeutic approaches for dyslipidemia.

EXPERT OPINION

The precise mechanisms for regulating lipid metabolism, particularly in kidney disease, are poorly understood. Guidelines for lipid-lowering therapy for CKD are controversial. Several hypolipemic therapies are available, but compared to others, statin therapy is the most common. No clinical trial has evaluated the efficacy of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) in preventing cardiovascular events or improving kidney function among patients with CKD or kidney transplant recipients. Attractive alternatives, such as PCSK9-small interfering RNA (siRNA) molecules or evinacumab are available. Additionally, several promising agents, such as cyclodextrins and the FXR/TGR5 dual agonist, INT-767, can improve renal lipid metabolism disorders and delay CKD progression. Drugs targeting mitochondrial dysfunction could be an option for the treatment of dyslipidemia and lipotoxicity, particularly in renal diseases.

Cinnamic Acid Attenuates Peripheral and Hypothalamic Inflammation in High-Fat Diet-Induced Obese Mice

Obesity is closely linked to chronic inflammation in peripheral organs and the hypothalamus. Chronic consumption of a high-fat diet (HFD) induces the differentiation of Ly6c^high monocytes into macrophages in adipose tissue, the liver, and the brain, as well as the secretion of pro-inflammatory cytokines. Although cinnamon improves obesity and related diseases, it is unclear which components of cinnamon can affect macrophages and inflammatory cytokines. We performed in silico analyses using ADME, drug-likeness, and molecular docking simulations to predict the active compounds of cinnamon. Among the 82 active compounds of cinnamon, cinnamic acid (CA) showed the highest score of ADME, blood–brain barrier permeability, drug-likeness, and cytokine binding. We then investigated whether CA modulates obesity-induced metabolic profiles and macrophage-related inflammatory responses in HFD-fed mice. While HFD feeding induced obesity, CA ameliorated obesity and related symptoms, such as epididymal fat gain, insulin resistance, glucose intolerance, and dyslipidemia, without hepatic and renal toxicity. CA also improved HFD-induced tumor necrosis factor-α, fat deposition, and macrophage infiltration in the liver and adipose tissue. CA decreased Ly6c^high monocytes, adipose tissue M1 macrophages, and hypothalamic microglial activation. These results suggest that CA attenuates the peripheral and hypothalamic inflammatory monocytes/macrophage system and treats obesity-related metabolic disorders.

Effects of cinnamon supplementation on lipid profiles among patients with metabolic syndrome and related disorders: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Studies in animals and humans have reported numerous beneficial effects of cinnamon. However, its hypolipidemic efficacy in patients with metabolic syndrome (MetS) and related disorders is still controversial. This meta-analysis aimed to evaluate the lipid-regulating effects and safety of cinnamon in a population with MetS and related disorders.

METHODS

Studies that met the inclusion criteria were retrieved from PubMed, Embase, Cochrane Library, and Web of Science. Randomized placebo-controlled trials of cinnamon or its extracts in the treatment of MetS and related metabolic diseases were the main eligibility criteria. The Cochrane Handbook was used to guide the study selection, quality assessment, and data analysis. All statistical analyses were performed using Stata 15.0.

RESULTS

Twelve studies involving 773 subjects were included in the meta-analysis. The overall results showed that cinnamon could significantly reduce total cholesterol (weighted mean difference [WMD]: -0.19 mmol/L [-7.34 mg/dL]; 95% confidence interval [CI]: -0.24, -0.14 [-9.27, -5.41]), triglyceride (WMD: -0.10 mmol/L [-8.85 mg/dL]; 95% CI: -0.16, -0.04 [-14.16, -3.54]), and low-density lipoprotein cholesterol (WMD: -0.16 mmol/L [-6.18 mg/dL]; 95% CI: -0.20, -0.11 [-7.72, -4.25]). In the subgroup analysis, cinnamon did not exhibit a significant effect on lipid profiles in European and American patients. Larger doses of cinnamon tended to exhibit better regulation of lipid profiles and high-dose cinnamon (≥1.5 g/d) significantly increased high-density lipoprotein cholesterol (WMD: 0.07 mmol/L [2.70 mg/dL]; 95% CI: 0.03, 0.11 [1.16, 4.25]).

CONCLUSION

The current evidence shows that cinnamon can regulate lipid profiles in patients with metabolic disorders.

Cinnamaldehyde treatment during adolescence improves white and brown adipose tissue metabolism in a male rat model of early obesity

Early obesity is a serious health problem and nutritional therapeutic strategies during young age may improve health outcomes throughout life. Cinnamaldehyde, major component of cinnamon, exhibits several beneficial metabolic effects....

Cinnamon as Dietary Supplement Caused Hyperlipidemia in Healthy Rats

Objective

Cinnamon is a cooking spice and a medicinal herb. It is increasingly used as a health supplement due to its perceived benefit to prevent and or manage type 2 diabetes and metabolic disorders. However, it is unclear if regular consumption of this medicinal plant will interfere with normal physiological functions. Therefore, this study investigated the impact of daily cinnamon supplements on glucose and lipid metabolic profiles in healthy rats.

Methods

Male rats (Sprague Dawley, 8 weeks) were supplied with cinnamon in their diet (equivalent to ∼1 g/day in humans) for two weeks. Blood glucose and lipid levels, as well as metabolic markers in both liver and abdominal white adipose tissue, were measured.

Results

Cinnamon significantly increased fat mass and blood cholesterol and low-density lipoprotein (LDL) levels, but reduced fasting blood glucose level by 12%. Liver functional enzymes were normal in rats consuming cinnamon. However, several lipid metabolic markers were impaired which may contribute to dyslipidemia, including two main switches for energy metabolism (sirtuin 1 and peroxisome proliferator-activated receptor-gamma coactivator-1α) and the LDL receptor. However, de novo lipid synthesis enzymes and inflammatory markers were also reduced in the liver by cinnamon treatment, which may potentially prevent the development of steatosis. Markers for lipid oxidation were downregulated in fat tissue in cinnamon-treated rats, contributing to increased fat accumulation.

Conclusion

Daily low-dose cinnamon supplementation seems to promote abdominal adipose tissue accumulation and disturb lipid homeostasis in healthy rats, raising the concerns regarding daily use in healthy people.

What is the influence of cinnamon supplementation on liver enzymes? A systematic review and meta-analysis of randomized controlled trials

Existing evidence has uncovered the potential health benefits of cinnamon intake; however, its effect on liver function is unclear. Thus, the aim of this systematic review and meta-analysis was to examine the effect of cinnamon supplementation on liver enzymes. Relevant articles were identified through a systematic search in PubMed/Medline, Scopus, Web of Science, Cochrane Library, and Embase up to September 2020. All trials assessing the effect of oral cinnamon supplementation on serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) in adults were included. The pooled effect sizes were obtained using the random-effects model and expressed as mean difference (MD) and 95% confidence intervals (CI). A total of seven original trials (nine treatment arms) involving a total of 256 subjects were included in the final analysis. The pooled analysis indicated that cinnamon supplementation had no significant effect on serum levels of ALT, AST, and ALP. However, there was a significant reduction in ALT levels in patients with type 2 diabetes (MD: -4.01 U/L; 95% CI: -6.86, -1.15) and in trials with low-dose supplementation (<1,500 mg/d), follow-up duration longer than 12 weeks, and in the elderly patients (aged>50 years). The beneficial effects of cinnamon intake were also shown in AST levels in patients with type 2 diabetes and trials with long-term follow-up (>12 weeks). Longer-term, oral cinnamon supplementation may improve serum levels of liver enzymes in patients with type 2 diabetes. Further high-quality studies are needed, especially in populations with abnormal liver enzyme levels, to firmly establish the clinical efficacy of cinnamon on liver function.

The effect of herbs and spices on risk factors for cardiometabolic diseases: a review of human clinical trials

Herbs and spices are recommended to increase flavor and displace salt in the diet. Accumulating evidence suggests herbs and spices may improve risk factors for cardiometabolic diseases. In this narrative review, an overview of evidence from human clinical trials examining the effect of herbs and spices on risk factors for cardiometabolic diseases is provided. Human clinical trials examining supplemental doses of individual spices and herbs, or the active compounds, have yielded some evidence showing improvements to lipid and lipoprotein levels, glycemic control, blood pressure, adiposity, inflammation, and oxidative stress. However, cautious interpretation is warranted because of methodological limitations and substantial between-trial heterogeneity in the findings. Evidence from acute studies suggests intake of mixed herbs and spices as part of a high-saturated fat, high-carbohydrate meal reduces postprandial metabolic impairments, including lipemia, oxidative stress, and endothelial dysfunction. Limited studies have examined the postprandial metabolic effects of incorporating mixed herbs and spices into healthy meals, and, to our knowledge, no trials have assessed the effect of longer-term intake of mixed herbs and spices on risk factors for cardiometabolic diseases. To inform evidence-based guidelines for intake of herbs and spices for general health and cardiometabolic disease risk reduction, rigorously conducted randomized controlled trials are needed, particularly trials examining herb and spice doses that can be incorporated into healthy dietary patterns.

The beneficial effects of cinnamon among patients with metabolic diseases: A systematic review and dose-response meta-analysis of randomized-controlled trials

This systematic review and meta-analysis aims to summarize and conclude the clinical evidence regarding the use of cinnamon among patients with metabolic diseases. A comprehensive literature search without any limitation on language was conducted using the following bibliographical databases: ISI Web of Science, Embase, Scopus, PubMed, and Google Scholar. Search was conducted up to 23 January 2020. A total of 35 clinical trials were included for final analysis. Pooling of results showed a significant reducing effect of cinnamon on total cholesterol (TC) (weighted mean difference (WMD) = -11.67 mg/dL; P = 0.010), triglyceride (TG) (WMD = -16.27 mg/dL; P < 0.001), low density lipoprotein-cholesterol (LDL-C) (WMD = -6.36 mg/dL; P < 0.001), serum glucose (WMD = -11.39 mg/dL; P < 0.001), serum insulin (WMD = -1.27 μIU/mL; P = 0.028), and waist circumstance (WC) (WMD = -1.68 cm; P = 0.016). These lowering effects on TG, TC, LDL-C, and serum glucose levels were robust in studies that used cinnamon supplementation dose ≤1.5 g. Also, our findings of the present meta-analysis showed that cinnamon supplementation could have favorable effects on high density lipoprotein-cholesterol (HDL-C, WMD = 1.35; P = 0.038) as well as systolic (WMD = -3.95 mmHg; P = 0.018) and diastolic (WMD = -3.36; P = 0.001) blood pressure among patients with metabolic diseases. The present meta-analysis suggests that cinnamon might exert beneficial effects on various cardiometabolic risk factors among patients with metabolic diseases.

Phytonutrient supplements and metabolic biomarkers of cardiovascular disease: An umbrella review of meta-analyses of clinical trials

Phytonutrients exert several pharmacological effects on humans. In this study, we performed an umbrella review of the association of phytonutrient supplements (PNSs) with biomarkers of cardiovascular disease. Relevant published systematic reviews and meta-analyses of clinical trials were identified by searching PubMed, Embase, and Cochrane Library until July 4, 2020. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) for summarized effects and I² statistics of heterogeneity were extracted from individual studies or reanalyzed using a random-effects model. Of the 50 included studies, pooled effects of PNSs on blood pressure, lipid profiles, and glycemic control were reported in 16, 25, and 14 articles, respectively. The findings appeared to be highly heterogeneous among individual trials of included systematic reviews and meta-analyses. Ginger (WMD = -6.36 mmHg, 95% CI = -11.27, -1.46) and Hibiscus sabdariffa (WMD = -7.58 mmHg, 95% CI = -9.69, -5.46) were associated with lowered systolic blood pressure, whereas Aloe vera, Nigella sativa, and spirulina were associated with beneficial effects on both lipid profiles and glycemic control. In summary, this umbrella review has provided up-to-date evidence for the effect of PNSs on biomarkers related to hypertension, dyslipidemia, and diabetes. The results must be interpreted with caution due to potential heterogeneity.

The effect of cinnamon supplementation on liver enzymes in adults: A systematic review and meta-analysis of randomized controlled trials

AIMS

The aim of this study was to perform a systematic review and meta-analysis of randomized controlled trials (RCTs) to examine the effect of cinnamon supplementation on liver enzymes.

METHODS

A systematic search was performed in electronic databases including PubMed-Medline, Scopus, and ISI Web of Science up to November 2020. We used a random effects model to estimate pooled effect size of alanine aminotransferase (ALT), alkaline phosphatase (ALP), and aspartate aminotransferase (AST) levels.

RESULTS

Seven RCTs (9 treatment arms) fulfilled the eligibility criteria of the present meta-analysis. Overall, meta-analysis could not show any beneficial effect of cinnamon supplementation on AST, ALT, and ALP. Subgroup analyses showed that the effect of cinnamon supplementation on ALT was significant at the dosages of <1500 mg/day (Hedges's: -0.61; 95 % CI: -1.11, -0.10; P = 0.002), in trials lasting>12 weeks (Hedges's: -0.83; 95 % CI: -1.36, -0.30; P = 0.01), and in trials conducted of both gender (Hedges's: -0.72; 95 % CI: -1.45, -0.01; P = 0.04).

CONCLUSION

In summary, cinnamon supplementation had no significant effect on liver enzymes in adults. However, the effect of cinnamon on ALT levels was significant at the dosages of <1500 mg/day, in trials lasting>12 weeks, and in trials conducted of both gender. Nevertheless, further studies should be performed to confirm our results.

Efficacy of Cinnamon as an Adjuvant in Reducing the Glycemic Biomarkers of Type 2 Diabetes Mellitus: A Three-Month, Randomized, Triple-Blind, Placebo-Controlled Clinical Trial

The major aim of this randomized, placebo-controlled, triple-blind clinical trial was to evaluate the efficacy of cinnamon as an adjuvant treatment in reducing glycemic levels in people with type 2 diabetes, compared to a placebo. The study was conducted between August and December 2019, with 160 people with type 2 diabetes, in five Primary Health Units, in Parnaíba, Brazil. Inclusion criteria were: persons of both genders using oral antidiabetic agents, with glycated hemoglobin ≥ 6.0%, and between 18 and 80 years of age. The primary outcome was change in glycated hemoglobin levels after 90 days of intervention. Other biomarkers evaluated were fasting blood glucose, insulin level, and HOMA-IR index. Participants were divided equally into two groups of 80 individuals each, and were given 3 g capsules of either cinnamon or placebo to be taken in combination with their usual oral antidiabetic agents. After 90 days, participants in the cinnamon group had statistically significant reductions of 0.2% of glycated hemoglobin and 0.55 mmol/L of fasting venous glucose, when compared with the placebo group. Cinnamon reduced the glycemic measures of persons with type 2 diabetes, albeit with modest reductions. TRIAL: RBR-2KKB6D.

In-situ reactive heat breaking cell wall by SO3 hydration: innovative cell-wall breaking technique to enhance extraction of cinnamaldehyde from cinnamon

Cinnamaldehyde (CA) is one of the major active pharmaceutical ingredient of cinnamon bark. Hydrodistillation (HD) is usually used in CA extraction, however, the extraction yield is lower. The cell wall is a key factor limiting the extraction of essential oils. In-situ reactive heat breaking cell wall (RHB) could destroy the cell wall, which was conducive to the diffusion of CA. The aim of this work was to examine the effect of RHB pretreatment to HD extraction. Response surface methodology (RSM) was used to optimize RHB pretreatment parameters, and Box-Behnken Design (BBD) method was performed to evaluate the effects of different operating parameters. The maximum yield was increased to 3.31 ± 0.11% (w/w) from 2.08 ± 0.042% (w/w) after RSM optimization. Scanning electron microscopic (SEM) analysis showed that RHB destroyed and disrupted the cell wall of cinnamon bark. The GC analysis demonstrated that the purity of cinnamaldehyde was improved and no new components were presented in the extraction product from the cinnamon via RHB pretreatment. In conclusion, RHB is an effective pretreatment method for the CA extraction, and also may be used in the other herbal medicine extraction.

The Association between Dyslipidemia, Dietary Habits and Other Lifestyle Indicators among Non-Diabetic Attendees of Primary Health Care Centers in Jeddah, Saudi Arabia

Diet and other lifestyle habits have been reported to contribute to the development of dyslipidemia in various populations. Therefore, this study investigated the association between dyslipidemia and dietary and other lifestyle practices among Saudi adults. Data were collected from adults (≥20 years) not previously diagnosed with diabetes in a cross-sectional design. Demographic, anthropometric, and clinical characteristics, as well as lifestyle and dietary habits were recorded using a predesigned questionnaire. Fasting blood samples were drawn to estimate the serum lipid profile. Out of 1385 people, 858 (62%) (491 men, 367 women) had dyslipidemia. After regression analysis to adjust for age, body mass index, and waist circumference, an intake of ≥5 cups/week of Turkish coffee, or carbonated drinks was associated with increased risk of dyslipidemia in men (OR (95% CI), 2.74 (1.53, 4.89) p = 0.001, and 1.53 (1.04, 2.26) p = 0.03 respectively), while the same intake of American coffee had a protective effect (0.53 (0.30, 0.92) p = 0.025). Sleep duration <6 h, and smoking were also associated with increased risk in men (1.573 (1.14, 2.18) p = 0.006, and 1.41 (1.00, 1.99) p = 0.043 respectively). In women, an increased intake of fresh vegetables was associated with increased risk (2.07 (1.09, 3.94) p = 0.026), which could be attributed to added salad dressing. Thus, there are sex differences in response to dietary and lifestyle practices.

Effect of cinnamon supplementation on blood pressure and anthropometric parameters in patients with type 2 diabetes: A systematic review and meta-analysis of clinical trials

BACKGROUND AND AIMS

The present systematic review and meta-analysis was conducted to investigate the effect of cinnamon supplementation on blood pressure and anthropometric indices in patients with type 2 diabetes.

METHODS

PubMed, Embase, Scopus, Web of Science and Cochrane Library were systematically searched to find relevant records up to 22 August 2019. Standard mean difference (SMD) and 95% confidence interval (CI) were used to evaluate the effect of cinnamon supplementation on the outcomes of this study. In the case of heterogeneity, fixed and random effect models were used. The obtained data were analyzed by Stata 13. After excluding irrelevant records, 9 eligible articles were included.

RESULTS

This meta-analysis found a significant reduction in systolic blood pressure (SBP) (SMD: -0.532, 95% CI: [-1.032, -0.033], P = 0.037) and diastolic blood pressure (DBP) (SMD: -0.681, 95% CI: [-1.297, -0.065], P = 0.030) of patients with type 2 diabetes following cinnamon supplementation. Based on the results of the present study, cinnamon supplementation had no significant effect on the body weight (BW) (SMD: -0.309, 95% CI: [-0.793, 0.175], P = 0.211), body mass index (BMI) (SMD: -0.550, 95% CI: [-1.244, 0.144], P = 0.120). and waist circumference (WC) (SMD: -0.235, 95% CI: [-0.518, 0.047], P = 0.103).

CONCLUSIONS

Cinnamon supplementation significantly decreased SBP and DBP of patients with type 2 diabetes. Although cinnamon intake caused changes in anthropometric parameters, the observed changes were not statistically significant.

Effects of probiotic, cinnamon, and synbiotic supplementation on glycemic control and antioxidant status in people with type 2 diabetes; a randomized, double-blind, placebo-controlled study

Purpose

The aim of this study was to investigate the effect of probiotic bacteria of Lactobacillus acidophilus, cinnamon powder and their combinations on the glycemic and antioxidant indices in patients with type 2 diabetes.

Methods

A total of 136 patients randomized with type 2 diabetes entered the study and were randomly divided into four groups who were matched for age and gender. Thereafter, alongside their routine pharmacotherapy, each group followed one of the following diets: Group A: Lactobacillus acidophilus 10⁸ cfu and 0.5 g of powdered cinnamon (synbiotic). Group B: Lactobacillus acidophilus (probiotic), Group C: powdered cinnamon. Group D: rice flour powder as placebo. At the beginning and end of the intervention, fasting blood sugar (FBS), HbA1c, advance glycation end products (AGE), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and antioxidant enzymes of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) were measured.

Results

Following 3 months of treatment, the mean FBS level was decreased significantly in probiotic, cinnamon, and synbiotic supplementation groups compared with control (P < 0.01). FBS levels in probiotic, cinnamon, and synbiotic groups were significantly decreased compared with the control group (P = 0.001, P = 0.063 and P = 0.001, respectively). The mean HbA1C in probiotic, cinnamon, and synbiotic groups were also decreased (P = 0.001, P = 0.001 and P = 0.04, respectively). The mean AGE in synbiotic group was significantly decreased (P = 0.037). Probiotic, cinnamon and synbiotic all could improve antioxidant enzyme activity modestly. However, the most significant effect was seen in probiotic group.

Conclusions

According to the current results, the use of probiotic supplements (individually or in combination with cinnamon) leads to a reduction in blood glucose and an increase in antioxidant enzymes in people with type 2 diabetes.

Identification of Cinnamaldehyde as Most Effective Fatty Acid Uptake Reducing Cinnamon-Derived Compound in Differentiated Caco-2 Cells Compared to Its Structural Analogues Cinnamyl Alcohol, Cinnamic Acid, and Cinnamyl Isobutyrate

Naturally occurring cinnamon compounds such as cinnamaldehyde (CAL) and structurally related constituents have been associated with antiobesity activities, although studies regarding the impact on intestinal fatty acid uptake are scarce. Here, we demonstrate the effects of CAL and structural analogues cinnamyl alcohol (CALC), cinnamic acid (CAC), and cinnamyl isobutyrate on mechanisms regulating intestinal fatty acid uptake in differentiated Caco-2 cells. CAL, CALC, and CAC (3000 μM) were found to decrease fatty acid uptake by 58.0 ± 8.83, 19.4 ± 8.98, and 21.9 ± 6.55%, respectively. While CAL and CALC at a concentration of 300 μM increased serotonin release 14.9 ± 3.00- and 2.72 ± 0.69-fold, respectively, serotonin alone showed no effect on fatty acid uptake. However, CAL revealed transient receptor potential channel A1-dependency in the decrease of fatty acid uptake, as well as in CAL-induced serotonin release. Overall, CAL was identified as the most potent of the cinnamon constituents tested.

Anti-hypertensive effects of cinnamon supplementation in adults: A systematic review and dose-response Meta-analysis of randomized controlled trials

Background & Objectives: Despite controversies, no earlier study has systematically summarized findings from earlier studies on the effect of cinnamon supplementation on blood pressure. Therefore, current systematic review and meta-analysis was done on the effect of cinnamon supplementation on systolic blood pressure (SBP) and diastolic blood pressure (DBP) in adults.Methods: Relevant studies published up to July 2019 were searched through PubMed/Medline, Scopus, ISI Web of Science, Embase and Google Scholar. All randomized clinical trials investigating the impact of oral cinnamon supplementation on any of the blood pressure parameters including SBP or/and DBP were included.Results: Out of 469 citations, 9 trials that enrolled 641 subjects were included. Cinnamon supplementation resulted in significant reduction in SBP (Weighted Mean Differences (WMD): -6.23 mmHg, 95% CI: -10.69 to -1.77, P = 0.006) and DBP (WMD: -3.93 mmHg, 95% CI: -6.33 to -1.52, P = 0.001). Greater effects on SBP were detected in trials using ≤2 g cinnamon, lasted ≥12 weeks and participants aged <50 years' old. DBP was also reduced by using lower doses. However, no significant non-linear associations were found between cinnamon supplementation dosage and study duration with both SBP (For dosage: P_{non-linearity} = 0.35, for duration: P_{non-linearity} = 0.21) and DBP (For dosage: P_{non-linearity} = 0.27, for duration: P_{non-linearity} = 0.41).Conclusions: We found a significant reduction in both SBP and DBP following cinnamon supplementation in adults. It could be proposed as a hypotensive supplement in hypertension management.

ATP-citrate lyase (ACLY) in lipid metabolism and atherosclerosis: An updated review

ATP citrate lyase (ACLY) is an important enzyme linking carbohydrate to lipid metabolism by generating acetyl-CoA from citrate for fatty acid and cholesterol biosynthesis. Mendelian randomization of large human cohorts has validated ACLY as a promising target for low-density-lipoprotein-cholesterol (LDL-C) lowering and cardiovascular protection. Among current ACLY inhibitors, Bempedoic acid (ETC-1002) is a first-in-class, prodrug-based direct competitive inhibitor of ACLY which regulates lipid metabolism by upregulating hepatic LDL receptor (LDLr) expression and activity. ACLY deficiency in hepatocytes protects from hepatic steatosis and dyslipidemia. In addition, pharmacological inhibition of ACLY by bempedoic acid, prevents dyslipidemia and attenuates atherosclerosis in hypercholesterolemic ApoE^-/- mice, LDLr^-/- mice, and LDLr^-/- miniature pigs. Convincing data from clinical trials have revealed that bempedoic acid significantly lowers LDL-C as monotherapy, combination therapy, and add-on with statin therapy in statin-intolerant patients. More recently, a phase 3 CLEAR Harmony clinical trial ("Safety and Efficacy of Bempedoic Acid to Reduce LDL Cholesterol") has shown that bempedoic acid reduces the level of LDL-C in hypercholesterolemic patients receiving guideline-recommended statin therapy with a good safety profile. Hereby, we provide a updated review of the expression, regulation, genetics, functions of ACLY in lipid metabolism and atherosclerosis, and highlight the therapeutic potential of ACLY inhibitors (such as bempedoic acid, SB-204990, and other naturally-occuring inhibitors) to treat atherosclerotic cardiovascular diseases. It must be pointed out that long-term large-scale clinical trials in high-risk patients, are warranted to validate whether ACLY represent a promising therapeutic target for pharmaceutic intervention of dyslipidemia and atherosclerosis; and assess the safety and efficacy profile of ACLY inhibitors in improving cardiovascular outcome of patients.

Assessment of Human Health Risk of Toxic Elements Due to Cinnamon Ingestion in the Diet

Recent studies highlighted the beneficial action of cinnamon on postprandial glycemia and LDL-cholesterol concentrations, both in healthy subjects and type 2 diabetic patients. Inclusion of 3 to 6 g of cinnamon in diet revealed a beneficial effect on glucose metabolism control in non-diabetic adults during postprandial period. Given the levels of toxic elements present in cinnamon species from different countries, such large daily intakes of cinnamon can easily exceed their maximum permissible limits and, consequently, induce adverse health effects. This study aimed to investigate the elemental concentration profile in cinnamon powder products available in the Portuguese market and to assess the cumulative non-carcinogenic risk to human health due to the exposure to mixtures of such elements through the inclusion of 6 g of cinnamon in diet. Concentrations of Cu, Zn, Fe, Al, Cl, Mn, and Sr were determined by wavelength dispersive X-ray fluorescence spectroscopy in different lots of eight branded and one bulk cinnamon powder products. Linear mixed models have revealed significant differences in concentrations of Zn, Fe, Al, and Cl between brands. In particular, bulk cinnamon samples presented the highest contents of Fe (475.0-490.0 mg kg^-1) and Al (1139.0-1336.0 mg kg^-1). The non-carcinogenic risk was assessed following EPA's guidelines through the hazard quotient (HQ). Estimated HQ values were lower than the USEPA guideline of 1. Additionally, the hazard index (HI), representing the combined non-carcinogenic effects of all toxic elements, revealed no potential human health risk for heavy consumers of cinnamon (HI = 0.660). AbstractGraphical ᅟ.

Effects of a nutraceutical combination of monacolin, γ-oryzanol and γ-aminobutyric acid on lipid profile and C-reactive protein in mice

INTRODUCTION

The aim of this study was to evaluate the efficacy of two nutraceutical agents aimed to improve lipid profile in a sample of mice.

MATERIAL AND METHODS

Fifty mice were randomly divided into four groups. Control mice were fed a standard diet (SD), while the other three groups were fed with a high-fat diet (HFD) for 4 weeks. At the end of the run-in period, mice fed with the SD continued to follow the SD, while mice fed with the HFD were divided into three groups: one continued with the HFD, one continued to follow the HFD + a blend of natural components derived from rice and fermented rice (monacolin K 3%, γ-oryzanol, and γ-aminobutyric acid) (S1), and the other one followed the HFD + one nutraceutical containing monacolin K 3% alone for 24 weeks.

RESULTS

The results showed that mice treated with HFD + S1 and HFD + S2 had lower levels of TC compared to mice fed with the HFD alone (p < 0.01, and p < 0.05, respectively). Moreover, mice treated with HFD + S1 had lower TC and LDL-C levels compared to mice fed with HFD + S2 (p < 0.05). Mice treated with HFD + S1 or S2 had lower Tg levels compared to mice fed with the HFD (p < 0.05).

CONCLUSIONS

We can conclude that a combination of monacolin K 3%, γ-oryzanol, and γ-aminobutyric acid is more effective than monacolin K 3% alone in reducing the negative effects of a HFD in a sample of specific pathogen-free mice.

Cinnamon supplementation positively affects obesity: A systematic review and dose-response meta-analysis of randomized controlled trials

BACKGROUND & AIMS

Data about the effects of cinnamon supplementation on obesity measures are conflicting. This systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to summarize the effects of cinnamon intake on body weight (BW), Body Mass Index (BMI), Waist Circumference (WC), and fat mass (FM) in adults.

METHODS

Online electronic search engines including PubMed, SCOPUS, Cochrane Library, and Google Scholar were searched to find pertinent articles until September 2018. Data were pooled using the random-effects method and were expressed as weighted mean difference (WMD) and 95% confidence intervals (CI). The non-linear association was assessed using fractional polynomial modeling.

RESULTS

Out of 679 records, 12 trials that enrolled 786 subjects were included. The pooled results showed that cinnamon administration significantly decreased BW (WMD: -1.02 kg, 95% CI: -1.66 to -0.38, P = 0.002), BMI (WMD: -0.51 kg/m², 95% CI: -0.74, -0.28, P < 0.001), WC (WMD: -2.40 cm, 95% CI: -4.48, -0.33, P = 0.02), and FM (WMD: -1.02%, 95% CI: -1.80, -0.24, P = 0.01). Greater effects on BW were observed in subjects aged <50 years old and those with a baseline BMI of ≥30 kg/m². The cinnamon administrations significantly reduced FM at the dosages of ≥2 g/d, when administered for ≥12 weeks. Cinnamon administration resulted in BW and WC reduction in non-linear fashion (P = 0.04).

CONCLUSIONS

Cinnamon supplementation significantly affects obesity measures. It could be recommended as a weight-reducing supplement in obesity management.

Effect of cinnamon (Cinnamomum Zeylanicum) supplementation on serum C-reactive protein concentrations: A meta-analysis and systematic review

OBJECTIVE

The effect of cinnamon (Cinnamomum Zeylanicum) on serum C-reactive protein (CRP), an acute phase protein commonly used as a marker of inflammation, is uncertain. Therefore, the objective of the present study was to conduct a systematic review and meta-analysis of published randomised controlled trials (RCTs) of cinnamon to determine the effect on levels of serum CRP, relative to controls.

DESIGN

Studies were identified by a search of electronic databases including PubMed, Cochrane Library, Google Scholar and Scopus before August 2018. Combined and stratified analyses were used. Weighted mean differences (WMD) and its 95% confidence interval were estimated for net change in serum CRP by using random-effects model. The heterogeneity of meta-analysis was assessed by χ² and I² test.

RESULTS

Six studies were identified, and data from 285 participants were included. Pooled analysis showed significant reductions in serum CRP (WMD: -0.81 mg/L, 95% CI: -1.36 to -0.26, p = 0.004), with significant heterogeneity between selected studies. Improvements in sub-group analysis were observed when baseline CRP levels were greater than 3 mg/dL, and in trials of >12 weeks duration. Doses <1500 mg/day and ≥1500 mg/day were effective in lowering serum CRP (WMD: -0.56 mg/dL, 95% CI: -1.01 to -0.10, p = 0.02 and WMD: -2.13 mg/dL, 95% CI: -4.08 to -0.19, p = 0.03), respectively, with significantly reduced heterogeneity in trials with lower doses of cinnamon <1500 mg/day (test for heterogeneity: P = 0.22 and I2 = 33%). No changes were found in controls.

CONCLUSION

Cinnamon supplementation improves levels of serum CRP, particularly in chronic conditions, where basal CRP levels are raised. Further well-designed studies are warranted to confirm or not the above-mentioned findings.