Provided is a method for blending a compound effective in preventing or improving aging of the skin into a chemically stable composition. Also provided is a method for increasing the uniform dispersibility of the compound in the composition. A compound represented by general formula (1), an isomer thereof, and/or a pharmacologically acceptable salt of these is dispersed in an oil agent having 0-2 hydroxyl groups to produce an oil-based composition, whereby decomposition of the compound is suppressed. A powder, solid fat, and/or semisolid fat is also included in the composition, whereby precipitation of the compound in the composition over time is suppressed. [In the formula, R1 represents a C1-4 linear or branched alkyl group substituted by a carboxyl group or a C1-4 linear or branched alkyl group substituted by a carboxylic acid ester group having a C1-4 alkyl chain, and R2 and R3 each independently represent a C1-4 linear or branched alkyl group.].本發明提供一種將在皮膚老化之預防或改善上有效的化合物，以化學上安定之方式摻合於組成物中的方法。再者，提供一種在前述組成物中，提高前述化合物之均勻分散性的方法。藉由使下述通式(1)所示之化合物、其異構物及/或該等之藥理學上可容許之鹽分散於具有0~2個羥基之油劑中，形成油性組成物，而抑制前述化合物之分解。又，藉由使前述組成物進一步含有粉體、固體脂肪及/或半固體脂肪，而抑制在前述化合物之組成物內之經時之沉降。[式中，R1表示經由羧基所取代的碳數1~4之直鏈或分枝之烷基、或經由具有碳數1~4之烷基鏈之羧酸酯基所取代的碳數1~4之直鏈或分枝之烷基，R2及R3各自獨立，表示碳數1~4之直鏈或分枝之烷基]。
