Total Flavanols
Also known as: Total flavanols, Flavan-3-ols, Catechins, Epicatechins, Procyanidins, Flavanols
Overview
Total flavanols are a group of polyphenolic compounds found in foods like cocoa, tea, apples, and certain fruits. They include monomeric catechins and epicatechins, as well as oligomeric procyanidins. Primarily studied for their cardiovascular benefits, effects on body composition, blood lipid profiles, endothelial function, and athletic performance, flavanols exhibit antioxidant properties and modulate vascular function, lipid metabolism, and exercise tolerance. Research maturity is moderate to advanced, supported by numerous randomized controlled trials (RCTs), systematic reviews, and meta-analyses. High-quality evidence supports cardiovascular and performance benefits, though heterogeneity exists due to varying doses and sources. They are generally recognized as safe with few side effects.
Benefits
Flavanols primarily improve endothelial function, measured by flow-mediated dilation (FMD), with optimal effects at approximately 710 mg total flavanols per day, particularly 50–150 mg of (−)-epicatechin daily. Studies show reductions in LDL cholesterol and triglycerides, with modest effects on body composition parameters like BMI and waist circumference. Meta-analyses report enhanced athletic performance and exercise tolerance. Secondary benefits include antioxidant and anti-inflammatory effects contributing to cardiovascular protection, and potential modulation of lipid metabolism and insulin sensitivity. Cardiometabolic improvements are observed in both healthy individuals and those with risk factors, while athletes benefit from improved exercise capacity. Benefits on endothelial function and lipid profiles are typically observed after weeks to months of supplementation, with athletic performance enhancements noted acutely and with short-term supplementation.
How it works
Flavanols improve endothelial function by enhancing nitric oxide (NO) bioavailability, leading to vasodilation. Their antioxidant activity reduces oxidative stress and inflammation. They also modulate lipid metabolism enzymes and signaling pathways. Flavanols interact with the cardiovascular system by improving vascular function and lipid profiles, with the musculoskeletal system by enhancing exercise tolerance and performance, and with the metabolic system by influencing glucose and lipid metabolism. Molecular targets include endothelial nitric oxide synthase (eNOS) activation and inhibition of LDL oxidation. Flavanols are absorbed in the small intestine, with monomers like epicatechin having higher bioavailability than oligomers, and are metabolized by gut microbiota, influencing systemic effects.
Side effects
Total flavanols are generally recognized as safe, with no serious adverse effects reported in clinical trials at studied doses. Common side effects are rare, with mild gastrointestinal discomfort reported in some individuals. Uncommon and rare side effects are not consistently reported. No major drug interactions have been reported, but caution is advised with anticoagulants due to potential mild antiplatelet effects. There are no established contraindications, but caution is advised in individuals with allergies to source foods. Limited data exists for pregnant or lactating women, but they are generally considered safe in adults.
Dosage
The minimum effective dose is approximately 50 mg of (−)-epicatechin per day for endothelial benefits. Optimal dosage ranges are around 710 mg total flavanols daily, with 50–150 mg of (−)-epicatechin showing maximal endothelial function improvement. There is no established upper limit, but doses above 900 mg total flavanols have been studied without adverse effects but with diminishing returns. Daily supplementation is recommended, with benefits accruing over weeks. Cocoa, tea, and apple-derived flavanols are common; standardized extracts are preferred for dose accuracy. Bioavailability is enhanced by food matrix and gut microbiota health. No specific cofactors are required, but overall diet quality may influence effects.
FAQs
Are total flavanols safe for long-term use?
Yes, clinical trials indicate good safety profiles with no serious adverse effects reported with long-term use.
How soon can benefits be expected?
Improvements in vascular function can be seen within weeks; lipid changes may take longer to manifest.
Can flavanols improve athletic performance?
Evidence supports modest enhancements in exercise tolerance and performance with flavanol supplementation.
Is more always better?
No; evidence shows an inverted U-shaped dose-response, with optimal effects at moderate doses of flavanols.
Do all flavanol sources have the same effect?
No; cocoa, tea, and apple flavanols differ in composition and potency, leading to varying effects.
Research Sources
- https://pmc.ncbi.nlm.nih.gov/articles/PMC5537860/ – This systematic review and meta-analysis examined the effects of tea, cocoa, and apple flavanols on body composition and blood lipid profiles. The findings indicated that flavanol supplementation significantly improved these parameters, although the effects were modest but consistent across studies. The review highlighted heterogeneity in flavanol sources and doses as a limitation but maintained high quality through rigorous meta-analytic methods.
- https://www.mdpi.com/2072-6643/15/21/4547 – This systematic review and meta-analysis focused on the impact of flavonoid supplementation on athletic performance. The analysis of RCTs revealed that flavonoid supplementation enhanced athletic performance and exercise tolerance significantly. The study acknowledged variability in flavonoid types and exercise protocols as limitations but provided comprehensive literature coverage.
- https://pubs.rsc.org/en/content/articlehtml/2019/fo/c9fo01747j – This meta-analysis investigated the effects of cocoa flavanols on endothelial function, assessed via flow-mediated dilation (FMD). The study found that optimal endothelial function improvement occurred at approximately 710 mg total flavanols per day, with the dose-response exhibiting an inverted U-shape. The analysis was limited to cocoa flavanols, which may restrict generalizability to other sources, but it employed high-quality dose-response modeling.
- https://pubmed.ncbi.nlm.nih.gov/37960199/ – This study investigates the impact of flavanol-rich foods on cognitive function and cardiovascular health. It suggests that regular consumption of flavanols may improve cognitive performance and reduce the risk of cardiovascular diseases by enhancing blood vessel function and reducing oxidative stress. The findings support the potential of dietary flavanols as a preventive strategy for age-related cognitive decline and cardiovascular issues.
- https://pubmed.ncbi.nlm.nih.gov/16794447/ – This research explores the effects of cocoa flavanols on blood pressure and vascular function. The study indicates that cocoa flavanols can significantly lower blood pressure and improve vascular health, particularly in individuals with hypertension. The results suggest that incorporating cocoa flavanols into the diet may be a beneficial approach for managing blood pressure and promoting cardiovascular well-being.
