Effects of short-term overfeeding with fructose, fat and fructose plus fat on plasma and hepatic lipids in healthy men

Abstract

Aims: The present study aimed to assess the effects of excess fat, fructose and fat-plus-fructose intakes on intrahepatocellular lipid (IHCL).

Methods: Healthy male subjects were studied after an isocaloric diet or a 7-day high-fructose (Fru: +3.5 g fructose/kg fat-free mass/day, +35% energy), high-fat (Fat: +30% energy as saturated-fat) or high-fructose, high-fat diet (FruFat: +3.5 g fructose/kg fat-free mass/day, +30% energy as fat, +65% total energy). IHCL was measured by (1)H magnetic resonance spectroscopy.

Results: All hypercaloric diets increased IHCL (Fru: +16%; Fat: +86%; FruFat: +133%; P<0.05). Very low-density lipoprotein (VLDL) triacylglycerols increased after Fru (+58%; P<0.05), but decreased after Fat (-22%; P<0.05), while no change was observed after FruFat.

Conclusion: Fat and fructose both increased IHCL, but fructose increased, while fat decreased, VLDL triacylglycerols. However, excess fat and fructose combined had additive effects on IHCL and neutralizing effects on VLDL triglycerides. This suggests that fructose stimulates, while fat inhibits, hepatic VLDL triacylglycerol secretion.