Chapter 3: Factors Affecting the Inter-individual Variability in the Cardiometabolic Response to Berry (Poly)phenols

Available literature suggests that berry (poly)phenols – especially anthocyanins, ellagitannins, phenolic acids, flavan-3-ols, and flavonols – have the potential to improve cardiometabolic risk factors such as hypertension, dyslipidemia, endothelial dysfunction, and arterial stiffness. Heterogeneity in the cardiometabolic effects amongst different population groups is also consistently reported. While factors such as bioavailability, gut microbiota, and genetic factors have been proposed as possible causes, the inter-individual variability in the vascular response to berry (poly)phenols has not been explored in detail. This chapter explores the evidence from human clinical trials, reviews, and meta-analysis of randomized-controlled trials (RCT). After summarizing the evidence related to the potential cardiometabolic health improvements following berry (poly)phenol consumption, we will address the influence of factors of inter-individual variability, including sex, body mass index (BMI), smoking, health status, and age. Finally, we will describe the limitations of the current evidence and the need for future studies to be specifically designed to assess inter-individual variability and analyze cardiometabolic effects on sub-populations and individuals.