Emulsifying dietary fat modulates postprandial endotoxemia associated with chylomicronemia in obese men: a pilot randomized crossover study

Abstract

Background: Postprandial hyperlipemia is recognized as a major cardio-metabolic risk factor, recently linked to the co-absorption of pro-inflammatory lipopolysaccharides with dietary lipids. This causes endotoxemia that is involved in the pathophysiology of obesity and insulin resistance, but to date the impact of food formulation is unknown. We tested a novel concept that endotoxin absorption can be modulated by fat emulsified structure in the meal, and potentially differently in obese vs. lean men.

Methods: In a randomized controlled crossover study, eight normal-weight and eight obese age-matched healthy men ingested two isocaloric, isolipidic breakfasts of identical composition including 40 g of milk fat that was emulsified or unemulsified. Plasma- and chylomicron-endotoxemia and chylomicron-triglycerides were measured during 8 h after breakfast ingestion.

Results: After emulsion consumption, parallel to an enhanced chylomicronemia, obese subjects presented an early and sharp increase in chylomicron-endotoxemia at 60 min (P time = 0.02), which was higher than (i) after spread fat in obese subjects (P < 0.05) and (ii) after both spread and emulsified fat in normal-weight subjects (P < 0.05). However in obese subjects, the iAUC of plasma endotoxemia over 8 h was lower after emulsion than after spread fat (P < 0.05) whereas in NW subjects such reduction of plasma LPS-iAUC was not observed (P = 0.67).

Conclusion: This study provides initial evidence that optimizing fat structure in the meal can be part of a dietary strategy to lower the metabolic impact of postprandial endotoxemia in obese men.

Trial registration: Registered at ClinicalTrials.gov # NCT01249378 on July 13, 2010.

Figures

Fig. 1

Consort flow diagram of the study participants

Fig. 2

Postprandial chylomicronemia expressed as cumulative iAUC of CMRF-TAG (a, b) and associated endotoxemia expressed as CMRF-LPS along postprandial time (c, d) in normal-weight (a, c) and obese (b, d) subjects. Black bars identify results after spread fat consumption whereas hatched bars identify results after emulsified fat consumption. a-b * P < 0.05, ** P < 0.01, paired Student’s t-test. §P < 0.05, unpaired Student’s t-test vs. NW subjects. c-d Two-way ANOVA used to test meal and time effects on CMRF-LPS (Pmeal, Ptime and Pmealxtime). d * P < 0.05, paired Student’s t-test. § P < 0.05, unpaired Student’s t-test vs. NW subjects. # P < 0.10 vs. 60 min, one-way ANOVA followed by Tukey test

Fig. 3

Postprandial cumulative plasma endotoxemia over 8 h in (a) normal-weight and b obese subjects. Black bars identify results after spread fat consumption whereas hatched bars identify results after emulsified fat consumption. b * P < 0.05 paired Student’s t-test