Metabolic Fate Modifications of Saturated Fats After an Overfeeding

Metabolic Fate Modifications of Saturated Fats After an Overfeeding

The purpose of this study is to determine the partitioning of exogenous lipids in the postprandial period while a study of overfeeding. The method is based on the incorporation of a stable isotopic tracer (d31_palmitic acid, d31_C16) in lipoprotein triglycerides (TG-CHYLOMICRON and TG-VLDL) and in free fatty acids (FFA).

Healthy overweight and lean young men are subjected to an overfeeding during 56 days which corresponds to a supplement of 761 Kcal/day. During two exploration days (before : D0 et after : D56 overfeeding) they have ingested a breakfast with tracer (d31_palmitic acid, d31_C16, 20mg/kg) and blood and urine samples were collected every hour of each exploration day. The enrichment in deuterium was measured by gas chromatography-organic mass spectrometry (GC-OMS) in palmitic acid pool of lipid fractions.

Inclusion Criteria:

• 18 to 55 years old
• BMI 18 to 30 kg/m²
• Stable physical activity
• Safety subject during medical consultation

Exclusion Criteria:

• Medical or surgical history which may affect energy expenditure (renal -cardiovascular -hepatic- endocrine-inflammatory diseases)
• Drug use that could affect energy expenditure (steroids, nicotine substitutes, thyroid hormones)
• Eating disorder
• Intensive sportive activity
• Subjects who Smoke
• Claustrophobic subjects