Beschreibung:
Dietary intake of the lipophilic antioxidant α‐tocopherol (α‐T) is poor with a significant proportion of Americans having suboptimal α‐T status. Although its bioavailability is limited in the absence of co‐ingesting fat, the extent to which quantity and composition of fat affects α‐T bioaccessibility (BA), and its potential to be absorbed, is not well established. We hypothesized that bovine dairy fat would dose‐dependently increase α‐T BA and that dairy milk containing primarily saturated fat would increase BA to a greater extent than soy milk containing primarily unsaturated fat. In vitro digestion was used to examine the BA of α‐T (36 mg) added to soy milk (2.5 g fat) or dairy milk containing fat at <0.5 g (non‐fat milk), 2.5 g (low‐fat milk), 5 g (reduced‐fat milk), and 8 g (whole milk). α‐T recovery following simulated gastric through small intestinal digestion was 87‐94.5% with no difference (P>0.05) between dairy or soy milks. α‐T BA increased in a fat‐dependent manner (P<0.05) from 37.3±1.7% in non‐fat milk to 55.2±0.7% in low‐fat milk to 61.7±1.9% in reduced‐fat milk, and to 69.7±2.6% in whole milk. BA of α‐T in soy milk (53.5 ± 3%) and low‐fat milk with equivalent quantities of fat were not significantly different. Fat quantity (0‐8 g), regardless of dairy or soy milk, was highly correlated to α‐T BA (r = 0.92, P<0.05). Thus, dietary fat dose‐dependently increases α‐T BA independent of degree of lipid saturation and supports a need to define the optimal quantity of fat on α‐T bioavailability in clinical studies. Supported by Dairy Research Institute.