Postprandial lipaemia induces an acute decrease of insulin sensitivity in healthy men independently of plasma NEFA...

Area of Science:

• Metabolic Health
• Endocrinology
• Nutrition Science

Background:

• Western diets frequently induce prolonged postprandial lipaemia, lasting up to 18 hours daily.
• Understanding the metabolic consequences of postprandial lipaemia is crucial for public health.

Purpose of the Study:

• To investigate the hypothesis that postprandial lipaemia diminishes insulin sensitivity.
• To differentiate the effects of elevated triglycerides versus non-esterified fatty acids (NEFA) on insulin sensitivity.

Main Methods:

• A randomized crossover study involving ten healthy volunteers.
• Administration of two virtually isocaloric meals designed to elicit varying postprandial lipid responses.
• Assessment of insulin sensitivity using an intravenous glucose tolerance test (IVGTT) with minimal model analysis, conducted in postabsorptive and postprandial states.

Main Results:

• Both meals significantly increased triglyceride levels postprandially.
• Meal 1, but not Meal 2, significantly elevated non-esterified fatty acid (NEFA) levels.
• Insulin sensitivity decreased by 53% after Meal 1 and 45% after Meal 2, indicating a comparable reduction regardless of NEFA levels.
• Postprandial triglyceride levels were similar between meals, but NEFA levels were higher after Meal 1.

Conclusions:

• Postprandial lipaemia leads to a significant reduction in insulin sensitivity.
• Elevated plasma triglyceride-rich lipoproteins appear to be the primary driver of decreased insulin sensitivity during postprandial lipaemia.
• The effect on insulin sensitivity is independent of concurrent changes in plasma NEFA levels.