Bioavailability and metabolism of dietary lipids

Abstract More than 90% of the lipids are present in the diet as triglycerides (TG), carrying three esterified dietary fatty acids (FAs) per triglyceride molecule. Phospholipids (PLs) are other important carriers of dietary FAs. Altogether, the daily intake of dietary FAs from TG and PLs will not ultimately lead to the same amount of FAs being released in the gut, and reaching the bloodstream or target organs, including the colon in the case of unabsorbed lipids. This chapter (i) summarizes the fate of dietary lipids during digestion that determines their bioaccessibility, (ii) describes cellular mechanisms of intestinal lipid absorption that drives the dietary FA release into the bloodstream, (iii) reviews how molecular and supramolecular lipid structures carrying dietary FAs (such as TG vs. PLs, emulsion vs. bulk oil, emulsifier type, etc.) can modulate their bioaccessibility and bioavailability, (iv) reviews their impact on health and metabolism as related to their supplied form of interest in the field of food and supplement formulation and processing standpoint, and (v) presents the recent “food matrix” concept that must be taken into account when studying the bioavailability and metabolism of dietary lipids.