RESUMEN
Significant differences have been reported in the composition of skin surface lipid in pre-pubertal subjects when compared to pubertal subjects. Analytical studies were performed to determine whether group mean changes in the fatty acid composition of the triglyceride and wax ester fractions of sebum could be detected in pre-pubertal versus pubertal subjects. Twenty males (ages 6-9), twenty females (ages 6-9) and twelve teenagers (ages 11-16) were studied. Skin surface lipid was examined by densitometry and gas chromatography. There were significant changes in the fatty acid composition of the wax fraction of sebum in the 11-16-year-old children when compared to the 6-9-year-old group. As wax is of sebaceous gland origin, this may represent a change in sebum composition probably in response to the hormonal stimulus. Changes in the fatty acid fraction of triglycerides were also noted with age, but this may be due to the change in source of triglyceride from predominantly epidermal origin to sebaceous gland origin.