There is a tendency to trivialise the skin, says Peter Elias, a dermatologist at the University of California, San Francisco. And yet this largest organ of the body is vital to health, keeping moisture in and germs out. Many things can interfere with these functions. Dry weather draws moisture from the skin. Bathing or showering too often—more than once per day—or using harsh cleansers that strip away naturally occurring oils, can also cause problems. When the skin becomes too dry, it can become itchy and inflamed. Dryness can also cause cracks in the skin which can lead to infections.
Some people are more prone to skin dryness than others. According to the American Academy of Dermatology, olive-skinned people are less likely to have dry skin than people with black, brown or fair skin. Men also have thicker, oilier skin, so they are less likely to experience dryness. Genetic ailments, such as ichthyosis, can cause dry and scaly skin, and so can diabetes or kidney disease.
Age is also a factor. The skin naturally produces an oil called sebum that coats, protects and moisturises the skin. Oil production tends to peak during puberty—the reason for those pesky pimples—and then slowly decreases over time.
The three types of moisturiser can help. Humectants, such as hyaluronic acid and glycerin, pull moisture from inside the body onto the surface of the skin. Occlusives, such as petroleum jelly and shea butter, block water from evaporating from the skin. Emollients, such as ceramide, smooth the skin by filling in gaps between skin cells. A review published in January in Experimental Dermatology found that ceramide made skin look and feel smoother and also reduced inflammation of the skin.
If the goal is soft, well-hydrated skin, experts say that cheaper products work just as well as the boutique options. “You don’t need to break the bank,” says Nour Kibbi, a clinical associate professor of dermatology at Stanford University. Where splurging may pay off, says Abigail Waldman, a dermatologist at Brigham and Women’s Hospital in Massachusetts, is on products that reduce the signs of ageing. As people age, skin-cell production slows and the skin thins. Older people also produce less collagen, which keeps the skin plump. This combination leads to wrinkles.
Retinol and other retinoids, a class of products chemically derived from vitamin A, reduce the appearance of wrinkles by increasing cell and collagen production. A study published in JAMA Dermatology in 2007 tested the effectiveness of retinol by comparing the arms of 36 elderly people who, three times a week, had had lotion with retinol put on one arm and lotion without retinol on the other. After six months, the researchers found that the arms with retinol had fewer fine wrinkles. Nearly 20 years later, experts still recommend retinol as a way to reduce the signs of ageing.
TikTok influencers are keen to sell these so-called “anti-ageing” products to their Gen Z customers to delay or prevent ageing. But there is no benefit to prophylactic use, says Dr Waldman. “The only product on the market that is truly anti-ageing is sunscreen,” says Zoe Draelos, a dermatologist at Duke University. Sunscreen can prevent damage from ultraviolet light that can cause sunspots and wrinkles. For all their benefits, however, ingredients such as retinol and glycolic acid can also cause redness, irritation, dryness, and cracks in the skin. Which might mean another trip to the shops for even more moisturisers.■
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