When it comes to skin types, having dry skin can be one of the most frustrating. It shows up in symptoms like flaky, itchy and dull skin that is sensitive and feels tight. And on top of having dry skin, it can also be dehydrated — lacking water — which, while not a skin type, is another condition to deal with.
But when it comes to dry skin, improving the skin barrier — the outermost layer of the skin that protects and helps retain water and moisture — is the most important. The skin barrier is made of oils that bind the skin cells together and has about 10-30 percent water content. When that skin barrier is healthy, the skin is properly moisturized, supple, flexible and better adept at naturally shedding dead skin cells. And when it is not, it appears dull, flaky and rough. If it gets too dry, it can also be seen with red scaly patches, fine lines or cracks or even deep cracks that can bleed.

What Causes Dry Skin?
Ceramides are lipids that help form the skin barrier and help retain moisture — but some people’s bodies do not produce enough of this protein, thanks to their genetic makeup. And this leads to drier skin. “The point of them is to not just create a barrier, but also help the skin build up its ability to hold its own water,” says Nancy Samolitis, M.D., board-certified dermatologist at Facile Dermatology + Boutique in West Hollywood, CA.
The most common causes are over-washing
or washing with drying products
and not moisturizing.
People who experience dry skin can also experience conditions such as atopic dermatitis — a type of eczema — or ichthyosis vulgaris. These are associated with dry skin because they involve a defective skin barrier. Other genetic changes that can predispose people to have dry skin is a mutation in the filaggrin gene, a gene responsible for making a protein called profilaggrin, which is an important protein in the skin barrier. In fact, 20-30 percent of people with atopic dermatitis have a filaggrin gene mutation, and it can be inherited. “[The filaggrin gene] helps strengthen [the skin barrier] and is also involved in the production of molecules involved in the ‘natural moisturizing factor’ [oil] in the skin, which helps to maintain hydration in the skin,” says Marisa Garshick, M.D., board-certified dermatologist at MDCS in New York.
As we age, skin also tends to get drier because of the natural mechanisms that keep our skin healthy kind of slow down with age. “People tend to be oilier when they’re teenagers because they have hormones stimulating their oil glands, but women’s hormones decline with age, so the lower the estrogen is, the drier the skin is,” says Samolitis.
Dry skin can also be a consequence of factors ranging from low humidity in the wintertime; central heating, which can result in drier air; prolonged exposure to water, especially hot water; or irritating or harsh products that strip the skin of its natural oils.
“The most common causes of dry skin [are] over-washing or washing with drying products and not moisturizing,” says Heidi Waldorf, M.D., a board-certified dermatologist at Waldorf Dermatology Aesthetics. “Soaps containing alkaline detergents can strip the important proteins and lipids that make up the brick and mortar of a healthy skin barrier.” But it is not just about topical products, any type of sun damage can affect the skin. “As your skin gets sun damaged, it’s not able to repair and protect itself as well,” says Samolitis.
Your Dry Skin Routine
Skincare
Limiting excess exposure to water and irritating ingredients, and maximizing moisturizer is key to helping and restoring the skin barrier. “Moisturizers that contain glycerin, urea, hyaluronic acid or other humectants or alpha hydroxy acids, which exfoliate and improve hydration, are good choices,” says Waldorf. “The ideal moisturizer contains a humectant to pull moisture in like a sponge, an emollient to smooth the areas between skin cells and give a silky feel and an occlusive to seal in moisture.”
Serums containing hyaluronic acid are also a great choice, and they can work even better when combined with occlusive and emollient ingredients, which complement the humectant properties of hyaluronic acid. “Look for occlusive ingredients like petroleum or dimethicone to form a protective seal over the skin,” adds Joshua Zeichner, M.D., director of cosmetic and clinical research at Mount Sinai Hospital in New York City. “Also look for emollient ingredients like natural oils that act as emollients to smooth rough cells and fill in cracks in the outer skin layers.”
Last but not least, be careful of cleansers. “There are cleansers that don’t strip the moisture out of your skin, but if you’re searching for that squeaky-clean feel, it’s removing some of your skin barrier,” says Samolitis. “Look for a creamy or oil-based cleanser.”
Diet
Although the relationship with diet and skin can be controversial, there are certain foods that can dry out the skin: coffee, alcohol and salt. “Salt and water try to live in balance in our bodies,” says Garshick. “If you consume too much salt and don’t drink enough water, your body tries to take water from your skin, which leads to dry and dehydrated skin.” And both caffeine and alcohol are diuretics, which means they can increase the frequency of urination and eliminate too much water if consumed in excess.
There is some thought that consuming foods high in omega-3s and omega-6s can help dry skin by strengthening the skin barrier. This includes fish like salmon, tuna, trout and olive oils. In fact, the skin is the first place to show signs of omega-3 deficiency because it is typically expressed in fatty acid deficiency, and it can manifest in rough patches on the skin, dandruff or chicken skin. Additionally, nuts are rich in vitamin E, which is known to protect the skin from oxidative cell damage and protect the skin barrier from external damage like UV rays.

And while you may assume that you need to drink water to add hydration back to dry skin, there is a lack of research on how much drinking water really affects the outer layers of the skin.
In fact, experts have found that this principle does not really apply to thirsty skin — once you are hydrated enough with the recommended water intake a day, eight 8-ounce glasses of water, more may not have any effect on your skin.
All in all, dry skin is a skin type that is mostly genetic and also includes a compromised skin barrier. You can definitely make an already existing condition worse with certain practices, but with a proper skincare routine, you can tackle dry skin before it hits. “Remember to follow these guidelines every day, all year round,” says Waldorf. “Don’t wait to feel dry.”