The present inventors focused on certain nutritional compositions known to have activity of controlling blood glucose levels. These foods were administered to rats for long periods, and real-time PCR was used to analyze the expression of genes associated with lipid metabolism in the liver and adipose tissues. As a result, the present inventors found that the expression of the PPARα gene is enhanced by these foods, and that this is accompanied by suppressed expression of fatty acid synthase and enhanced expression of a group of PPARα target genes associated with fatty acid metabolism. The present inventors also confirmed the effect of these foods in enhancing the expression of PPARγ and adiponectin, and discovered that these foods have the activity of enhancing the production of PPAR and PPAR-associated factors.