Cell turnover is the continuous process by which new skin cells - born at the deeper layer of tissue in your epidermis - replace old and dead ones on the surface of your skin and subsequently replacing them with younger cells. It is responsible for keeping your skin looks young and healthy─ helping rid your complexion of fine lines and blemishes, reducing pigmentation, and preserving elasticity.

During this process, the dead cells should slough off naturally. Still, the aging process, along with free radical damage and other environmental stressors, can lead to build-up on the skin, conditions like acne, wrinkles, age spots, hyperpigmentation, and more.

This guide will explain how the skin cell turnover process works, and the key factors affecting it and share why it matters for skin conditions such as acne, wrinkles, hyperpigmentation, and more.

What is exactly Skin Cell Turnover?

Skin cell turnover is an important process in our body by creating new skin cells to replace existing ones. Your skin is exposed to damage every day, whether by Sun UV radiation, scratches or bruises, rashes, bacteria, fungus, and numerous other sources. To fix this damage and keep your skin healthy, your body needs to produce a new supply of skin cells constantly. During this process, new cells move up from the deepest layer of the skin - called the subcutaneous layer - up to the dermis, and finally to the epidermis — the thin layer of skin exposed to the air – as dead cells. 

On average, the cell turnover process takes an estimated 14-21 days before the early 20s, 28 days between 20s and 30s, 45 to 60 days in 40s, and 60-90 days for 50 years old and more; it is a continual process that is always going on. Not only does your body replace old cells with new ones, but it also removes the dead cells that can accumulate on the surface layer of your skin through a process called exfoliation.

Like all biological processes, this process can be affected by various factors; for example, your diet, hormones, sleep patterns, stress level, sun exposure, weather, and seasonal variations all play a big role in promoting healthy skin cell turnover.

While your skin can handle the cell turnover process just fine on its own eventually, the new skin cells will push abreast of their own, and therefore the old ones will fall off whether you exfoliate or not; they exfoliate on their own. However, pollution and other factors result in a clogged pore and get a dull-looking skin. So, to protect your skin, you must exfoliate!

Chemical or Physical exfoliation?

You can use either physical or chemical methods to exfoliate your skin, and as both get the job done in different ways, you may be asking yourself, "What's the difference?" and "Which is better?”. 

Exfoliation is an essential step in your skincare daily routine to maintain that healthy glow, improve skin texture and tone, and prevent pesky breakouts. Exfoliation works to remove the oldest layer of your skin cells and make a place for new cells to come in. 

Physical exfoliants

Physical exfoliants are products or tools that require rubbing or scrubbing actions. They play a big role in speeding up our natural exfoliation rate to keep skin soft, smooth, and healthy; it is essential because the natural exfoliation process decreases as we age. This kind of exfoliation contains tiny particles such as salt grains, sugar, jojoba beads, or nutshell granules to remove dead skin cells on the skin surface. Physical exfoliation removes dead skin cells and stimulates blood circulation, which may help with lymph drainage and reduce puffiness.

Chemical exfoliants

The most common chemical exfoliants are Alpha Hydroxy Acids (AHAs), Beta Hydroxy Acids (BHAs), and Fruit enzymes sourced from natural substances such as sugar cane, grapes, citrus, and milk,

• AHA’s: Most Alpha Hydroxy Acids (AHA) - Glycolic Acid & Lactic Acid - are naturally sourced from sugar, milk, and fruit, and they’re gentle and much better for sensitive skin than scrubs. Physical exfoliants sand the skin’s surface, whereas acids break apart the bonds that hold dead skin in situ without causing collateral irritation. And they have a bonus when used regularly by increasing cell turnover; you’re going to encourage the creation of new collagen, so you’ll see a firming effect over time. However, please note that AHAs like glycolic acid can leave your skin sensitive to the sun, so make sure to apply 30 SPF broad-spectrum sunscreen.
• BHA’s: Salicylic acid (BHA) Salicylic acid is a part of the beta-hydroxy acid family (BHA), a carbon-based organic ingredient naturally sourced from willow bark. It is a great ingredient for deep skin exfoliation, especially to decrease the appearance of blackheads and whiteheads. This fat-soluble acid penetrating follicles and skin, loosening the attachments between cells in the outer layer of the skin. These attachments are called desmosomes that hold the skin together, dissolving the dead skin cells clogging your pores. Salicylic Acid (BHA) is great for people with traditionally problematic or acne skin. It also works to constrict the pore diameter, which helps reduce the risk of future pores clogging and the appearance of blackheads or whiteheads.
• Fruit enzymes: Enzymatic exfoliants are another form of a chemical exfoliant as a best option for sensitive skin. Enzyme chemical exfoliators can be sourced, for example, from Papaya ''Papain'' or Pineapple ''Bromelain; they dissolve and digest keratin protein into smaller particles, revealing smoother skin. Enzymes are fruit-derived and lack acids or granules working on the skin's surface and slowly digest cellular build-up, making them the perfect way to introduce your skin to exfoliation.

Cell turnover and aging? 

On average, Cell turnover takes an estimated 40 to 56 days for your skin to completely turn over. Still, that timeline only lengthens as we age. This slowdown has several effects on the appearance of your skin because dead cells can linger for longer on your skin, which increases the risk of wrinkles, sagging and make hyperpigmentation - which is patches in skin that are unusually darkened due to excessive production of melanin - more common.

Skin Cell Turnover and Acne

Acne develops when a mixture of dead skin cells and sebum - a kind of natural oil produced by your body’s sebaceous glands - collects inside hair follicles. When the dead skin cells and sebum build up inside the follicle, the follicle can clog, resulting in acne.

How to encourage my Cell Turnover? 

You can encourage quicker cell turnover internally and topically through a specific diet and specially formulated skin care products. Your body requires vitamins and minerals for optimal skin health, and you can better ensure that you get them all by eating a variety of fresh vegetables, fruits, whole grains, and lean proteins, and (Omega) fatty fish. Vitamin A (retinol) is one of the vitamins linked to skin cell turnover.