The present invention provides a novel substance that promotes expression of filaggrin gene involved in improvement of the moisture retention function of skin. The inventors of the present invention found that expression of filaggrin gene fluctuates rhythmically over a roughly 24 hour cycle, screened candidate substances based on the time at which expression reaches a maximum following addition of the candidate substance, and identified zanthoxylum extract, 3-(1′-piperidine)propionic acid, geranium oil, cypress oil, rose oil, galvanum oil, pepper oil, basil oil, methyl-o-toluate, methyl anthranilate and dimethyl anthranilate as filaggrin gene expression promoting agents.
