Cell Turnover
Cell Turnover — the continuous process by which skin sheds old cells from its surface and replaces them with newer cells rising from the deeper layers of the epidermis. In healthy adult skin this cycle takes roughly 28 to 40 days, though it slows with age and can be influenced by factors like sun exposure and certain ingredients.
Key points
- New keratinocytes form in the basal layer of the epidermis and gradually migrate upward toward the surface.
- A well-functioning turnover cycle helps maintain smooth texture, even tone, and an intact skin barrier.
- Turnover naturally slows with age, which can contribute to duller-looking skin and a build-up of surface cells.
- Ingredients such as retinoids and alpha-hydroxy acids are often associated with supporting a more regular shedding process.
- UV damage, hormonal shifts, and some skin conditions can alter the normal pace of turnover.
Frequently asked
How long does one cell turnover cycle take?
In healthy adults it typically takes about 28 to 40 days, though this generally lengthens as we get older.
Can skincare speed up cell turnover?
Certain ingredients like retinoids and exfoliating acids are studied for their role in supporting surface renewal, but individual results vary and this is educational information, not medical advice.
Related topics
This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.
