LAUSR

Flavonoids and phenolic acids (polyphenols) are naturally-occurring bioactive compounds from plants, often found in high amounts in many foods and beverages. They are also present in many plant based dietary supplements, at levels up to pharmaceutical doses. The pathways of absorption and metabolism of the most common dietary polyphenols are now mostly understood. The enzymes involved, their site of action, essential transporters and exact conjugating enzymes have been characterised, and in vitro mechanistic experiments have been supported by numerous studies, using healthy volunteers, ileostomists, intestinal perfusion, and animal models. Since the types of metabolites in blood have been identified and some synthesised, we can more carefully design in vitro experiments and translate the findings into human intervention studies. The long-term health risks of excess dietary sugar consumption remains a controversial topic in nutrition. Some of the deleterious effects of dietary sugar have been linked to high blood glucose “spikes” following a meal or beverage, which are more extreme and uncontrollable in subjects with metabolic syndrome. Certain dietary polyphenols attenuate blood glucose after a high carbohydrate meal, and in addition, the absorbed polyphenols also help to repair or prevent the damage cause by high glucose. The combination of effects is essential for the overall action of dietary polyphenols where the consequence is maintenance of normal body metabolism and reduction in the risk of developing type 2 diabetes.