Polyphenol-blend may boost ‘health-related quality of life’ for overweight and obese adults: Study 24-Feb-2021 By Stephen Daniells Daily supplementation with a blend of polyphenol-rich extracts from grapefruit, grape, green tea, guarana and black carrot may improve health-related quality of life (HRQOL) by over 5%, says a study using Fytexia’s Fiit-ns ingredient.