Amino Acids

, Volume 44, Issue 2, pp 519–528

Dietary l-leucine and l-alanine supplementation have similar acute effects in the prevention of high-fat diet-induced obesity


  • Anne Freudenberg
    • German Institute of Human Nutrition in Potsdam-Rehbruecke (DIfE)
    • German Institute of Human Nutrition in Potsdam-Rehbruecke (DIfE)
  • Susanne Klaus
    • German Institute of Human Nutrition in Potsdam-Rehbruecke (DIfE)
Original Article

DOI: 10.1007/s00726-012-1363-2

Cite this article as:
Freudenberg, A., Petzke, K.J. & Klaus, S. Amino Acids (2013) 44: 519. doi:10.1007/s00726-012-1363-2


High-protein diets have been shown to alleviate detrimental effects of high-fat diets and this effect can be partially mimicked by dietary l-leucine supplementation. Here, we aimed to elucidate the early mechanisms and the specificity of leucine effects. We performed a 1-week trial with male C57BL/6 mice fed ad libitum with semisynthetic high-fat diets containing an adequate (10 % w/w, AP) or high (50 % w/w, HP) amount of whey protein, or supplemented with l-leucine corresponding to the leucine content within the HP diet (Leu) or supplemented with equimolar l-alanine (Ala). Food and water intake were monitored continuously using a computer-controlled monitor system and body composition changes were assessed using quantitative NMR. HP completely prevented the AP-induced accumulation of body fat. Leu and Ala resulted in a similar reduction of body fat accumulation which was intermediate between AP and HP. There were no significant effects on plasma glucose or insulin. Triacylglycerol content and gene expression of lipogenesis enzymes in liver as well as plasma cholesterol were reduced by HP compared to AP with Leu and Ala again showing intermediate effects. Body fat gain and liver triacylglycerols were strongly correlated with total energy intake. Water intake was rapidly increased by HP feeding and total water intake correlated strongly with total amino nitrogen intake. We concluded that the positive effects of high-protein diets on metabolic syndrome associated traits are acutely due to effects on satiety possibly linked to amino nitrogen intake and on the subsequent suppression of liver lipogenesis without evidence for a specific leucine effect.


High-protein dietl-Leucine supplementationl-Alanine supplementationSatietyEnergy intakeWater intakeMetabolic syndromeDiet-induced fatty liver

Supplementary material

726_2012_1363_MOESM1_ESM.doc (58 kb)
Supplementary material 1 (DOC 57 kb)

Copyright information

© Springer-Verlag 2012