While the problems of young lips are well known, how lips and the lip area do precisely evolve during the different steps of ageing, remained to be documented.
Actually, the most common problems affecting lips, dryness and chapping, tend to peak in the 30 somethings. For older women, other issues - such as dull colour, loss of fullness, and an increasing vaguely defined contour of lips - increase along with ageing.
In a first part of the study, the researchers of Kao Corporation have analysed facial photographs of 139 Japanese women from 16 to 78 years of age. Results show that both the thickness of the upper and lower lips, and that of both together showed a decreasing trend associated with ageing. Furthermore, the width of the lips broadened with age and fullness of the lower lip shown in lateral views was significantly reduced.
The study also found that the white upper lip area under the nose became extended with age. A more detailed investigation by age group showed these changes start around 40 years of age. According to Kao, this phenomenon is attributable to the effects of inner tissue changes and muscular drooping.
In a second part of the study, Kao researchers enrolled thirteen Japanese women aged 46-55 years in 2015, then measured and compared various lip area sites in facial photographs taken in 1992, 2002, and 2015.
Comparisons of measurements obtained in the same participants confirmed that with age the lips became extended horizontally and nose-lip distance was also increased.
The study allowed Kao to get quantitative data on a phenomenon which was generally observed but scarcely measured. The way lips and the lips area change with age has been clarified and documented. According to the Japanese group, these findings will facilitate the development of new cosmetic and make-up products.