[Nutritional importance of phenolic compounds in the diet]

Phenols are one of the major groups of nonessential dietary components appearing in vegetable foods. They are a wide chemical compounds group that are considered as secondary plant metabolites, with different activity and chemical structure, including more than 8,000 different compounds. Phenols, has traditionally been considered as antinutritive compounds due to the adverse effect of one of their main components, tannins, on protein digestibility. However, actually there is an increased interest in these compounds because they have been associated with the inhibition of atherosclerosis and cancer. The bioactivity of phenolics may be related to their antioxidant behaviour, which is attributed to their ability to chelate metals, inhibit lipoxygenase and scavenge free radicals. This review make a global view on the main phenolic compound groups, their organoleptic effects in vegetable foods, their physiological effects in humans, their metabolism, bioavailability as well as their content in the diet.