Cholesterol

What does cholesterol do for skin?

Think of the outermost layer of your skin as a brick wall: the flat, dead skin cells are the bricks, and a thin layer of fats is the mortar that keeps water in and irritants out. Cholesterol is part of that mortar. A German review explains that the fat layers between skin cells “are formed mainly from ceramides, free fatty acids and cholesterol”, and that losing them weakens the barrier.

When you see Cholesterol on an ingredient list, it is there to top up that mortar. It is common in barrier creams that also list ceramides. Your skin makes its own supply in the outer layers; the cream version is there to add to it.

Why does skin run low on barrier fats?

Age and winter are the two best documented reasons. A UK study at Unilever that collected skin fats from women with tape strips found significantly lower levels of all the major barrier fats with increasing age, and levels at every body site tested were “dramatically depleted in winter compared with spring and summer.” The authors linked this to why older skin gets dry and easily upset, especially in the winter months.

Older skin also makes less cholesterol of its own. US researchers studying skin barrier recovery noted that aged skin shows decreased fat production, “particularly a reduction in cholesterol synthesis.”

Does cholesterol help dry or damaged skin recover?

Some, when it is combined with the other barrier fats in the right balance. In a 1997 study from the University of California, San Francisco, researchers stripped the outer layer of skin with tape and then applied different fat mixtures. On the skin of 6 people around 80 years old, a mix with cholesterol as the largest share, in a 3:1:1:1 ratio with ceramides and two kinds of fatty acids, significantly sped up barrier recovery at 6 hours. The authors concluded the effect worked “provided that cholesterol is the dominant lipid and that the same mixture also accelerates barrier recovery in chronologically aged human skin.”

A 2002 study from Belgium tested a cream combining ceramides, cholesterol and linoleic acid on volunteers whose skin had been damaged with a harsh detergent. Applied twice a day for 14 days, it sped up barrier repair compared with a cream containing only two ceramides. The authors wrote that “ceramides combined with other skin lipids can improve barrier repair after damage.”

The pattern across these studies is that cholesterol works as part of a team. Products that list ceramides, cholesterol and fatty acids together follow that research more closely than a product with cholesterol alone.

How long until you notice a difference?

In the studies, barrier measurements improved within hours to 2 weeks, but those were tests on deliberately damaged skin. On everyday dry or tight skin, give a barrier cream with cholesterol 2 to 4 weeks of twice-daily use before judging it. Our guide to why everyone is talking about skin barrier repair explains what to look for.

How do you use cholesterol in a routine?

Use it in a moisturizer or barrier cream, morning and night, after any water-based serum. It pairs well with glycerin, which draws water in, and with niacinamide, which a Japanese study in skin cells found raised production of ceramides and, by a smaller amount, cholesterol. In dry winter air, a final occlusive layer on very dry spots helps keep the result, as we explain in our guide to humectant vs occlusive skincare.

Who should be careful with cholesterol?

Few people need to avoid it: the studies above did not report problems caused by cholesterol in creams. Because barrier creams are often rich, people with oily or breakout-prone skin may prefer a lighter lotion with the same fats. As with any new product, patch test first if your skin reacts easily, and see a dermatologist if dryness comes with cracking, bleeding or a rash that does not settle.