June 2026

Age is usually counted in birthdays, but biology does not always follow the calendar. Two people can be the same chronological age but show very different signs of skin aging. One may have smoother, more resilient skin, while another shows earlier wrinkles, dryness, uneven tone, or loss of elasticity. This difference points to the concept of biological skin age: how well the skin functions at the cellular and molecular levels. Like other aspects of aging, skin aging is shaped not [more…]

Skin aging is commonly divided into two categories: intrinsic aging, which reflects the natural decline of cellular function over time, and extrinsic aging, which results from environmental stressors such as UV radiation, pollution, oxidative stress, and lifestyle factors. While these categories describe the sources of aging-related damage, they do not fully explain the molecular mechanisms that cause skin cells to progressively lose their youthful repair capacity. One emerging proposed concept is skin epigenetic hydroxylation incompetence, or SEHI. This idea suggests [more…]