Endotoxemia is modulated by quantity and quality of dietary fat in older adults.

Background: Aging is an important determinant of the rate of atherosclerosis development, mainly through low-grade inflammation. Diet, and particularly its fat content, modulates the inflammatory response in fasting and postprandial states.

Objective: We aimed to study the effects of dietary fat on endotoxemia in healthy older adults.

Materials And Methods: Twenty healthy older adults were randomized to three diets, lasting three-weeks each, using a crossover design: 1. A Mediterranean diet enriched in MUFA with virgin olive oil. 2. An SFA-rich diet. 3. A low-fat high-carbohydrate diet enriched in n-3 PUFA (α-linolenic acid of plant origin) (CHO-PUFA diet). At the end of each period, after a 12-h fast, the subjects received a meal with a composition similar to the dietary period just completed. We determined the fasting and the postprandial plasma levels of lipopolysaccharide (LPS) and LPS-binding protein (LBP).

Results: In the fasting state, we observed lower LPS plasma levels after the consumption of the CHO-PUFA diet (P=0.046) in comparison with the consumption of the Med and SFA-rich diets. In the postprandial measurements, we observed a statistically significant increase in plasma levels of LPS (P=0.044) and a decrease in LBP (P=0.003) after the intake of the CHO-PUFA meal, whereas no postprandial changes were observed after the ingestion of the Med and SFA-rich meals.

Conclusion: Our results, together with those obtained in a previous study, support the concept that the consumption of the Med Diet, in contrast to a low-fat PUFA diet, constitutes a more suitable dietary lifestyle for preventing the development of atherosclerosis in a population at risk, such as older adults.