Meta-Analysis of the Effects of Foods and Derived Products Containing Ellagitannins and Anthocyanins on Cardiometabolic Biomarkers: Analysis of Factors Influencing Variability of the Individual Responses

Abstract

Understanding interindividual variability in response to dietary polyphenols remains essential to elucidate their effects on cardiometabolic disease development. A meta-analysis of 128 randomized clinical trials was conducted to investigate the effects of berries and red grapes/wine as sources of anthocyanins and of nuts and pomegranate as sources of ellagitannins on a range of cardiometabolic risk biomarkers. The potential influence of various demographic and lifestyle factors on the variability in the response to these products were explored. Both anthocyanin- and ellagitannin-containing products reduced total-cholesterol with nuts and berries yielding more significant effects than pomegranate and grapes. Blood pressure was significantly reduced by the two main sources of anthocyanins, berries and red grapes/wine, whereas waist circumference, LDL-cholesterol, triglycerides, and glucose were most significantly lowered by the ellagitannin-products, particularly nuts. Additionally, we found an indication of a small increase in HDL-cholesterol most significant with nuts and, in flow-mediated dilation by nuts and berries. Most of these effects were detected in obese/overweight people but we found limited or non-evidence in normoweight individuals or of the influence of sex or smoking status. The effects of other factors, i.e., habitual diet, health status or country where the study was conducted, were inconsistent and require further investigation.

A Review of Factors Affecting Anthocyanin Bioavailability: Possible Implications for the Inter-Individual Variability

“…Anthocyanins and anthocyanin-rich foods have been shown to display several biological activities which may have positive implications on human health, including anti-inflammatory, anti-diabetic, and antioxidant activities [2,3]. Especially important is their role in preventing cardiovascular health disease through modulation of risk factors such as blood pressure, platelet aggregation, and vascular function [1,5,6]. Furthermore, the intake of anthocyanins seems to have promising effect on cognitive function in humans, with both acute and long-term intakes [4].…”

Adherence to UK dietary guidelines is associated with higher dietary intake of total and specific polyphenols compared with a traditional UK diet: further analysis of data from the Cardiovascular risk REduction Study: Supported by an Integrated Dietary Approach (CRESSIDA) randomised controlled trial

“…Following DG did lead to increase in specific polyphenols that have been associated with health benefits (e.g. anthocyanins, flavanones, isoflavones, phenolic acids and lignans (84)(85)(86)(87) ). This suggests that consuming at least 5 portions of F&V/d and >50 % of cereal intake as wholegrain will lead to an enrichment in dietary polyphenol profiles above and beyond the large amounts of polyphenols supplied by beverages.…”

Polyphenols in human nutrition: from thein vitroantioxidant capacity to the beneficial effects on cardiometabolic health and related inter-individual variability – an overview and perspective

“…However, higher efficacy was demonstrated in the participants with BMI ≥ 25 kg/m 2 and in non-medicated individuals, revealing the inter-individual variability (117) . Similarly, the beneficial effects of ellagitannins and anthocyanins on selected cardiometabolic risk factors were found to be more prominent in overweight and obese subjects (118) , and the effects of hydroxycinnamic acids may be greater in individuals at higher cardiometabolic risk (119) .…”