The terms are often used interchangeably, but technically dry skin and dehydrated skin are not the same thing (and this has proved as fuel for countless Reddit threads). When our skin’s outermost layer — its barrier — isn’t working properly, it leads to symptoms we’d think of as dryness: itchy, flaky, and dull skin.
What’s the difference between dry skin and dehydrated skin?
Dry skin lacks oil. It’s a skin type — meaning that your skin just isn’t genetically programmed to produce the amount of sebum it needs. Without the sebum and its lipids, the skin isn’t able to retain moisture as well as it should, nor fortify skin’s protective barrier.
Dehydrated skin, on the other hand, occurs when your skin doesn’t have any water. It’s usually the result of external factors, says Mona Gohara, M.D., associate clinical professor of dermatology at Yale University. Unlike dry skin, which is just the result of natural dysfunction within skin, dehydration is typically self-imposed, says Gohara. “I’ve seen so many patients who just overdo with skincare products — over-exfoliating by scrubbing too hard, too frequently, which deteriorates the barrier and just leaves skin raw.” Even your lifestyle, like the weather and your diet, can limit your skin’s ability to retain water.
How to Tell if You Have Dry or Dehydrated Skin
Without that moisturizing sebum, dry skin appears flaky and rough, and it may feel itchy or uncomfortable. You’ll often see it around the mouth or nose as well as near the eyebrows. Dry skin is common on the body as well.
Dehydration, on the other hand, is a mixed bag. Redness is common, and there’s no issue with sebum here; in fact, dehydrated skin is also oilier (and more breakout-prone). Our natural inclination may be to strip away every drop of oil and slather on harsh treatments, but this only worsens breakouts and perpetuates the dehydration cycle. “Dumping a bunch of benzoyl peroxide on there essentially burns a hole through your barrier,” says Gohara.
If you’re not sure which you’re working with, consider the pinch test. It’s simple: Lightly pinch your cheek or arm. If your skin doesn’t return to normal immediately, it may have less turgor (or snap to it, so to speak), and may thus be dehydrated.
How do I treat dry skin?
Step 1: Exfoliate properly
While dry skin isn’t caused by the excess of dead cells on the skin surface, they can prevent moisturizing ingredients from reaching the impaired skin barrier that so desperately needs them. However, there’s a right way to exfoliate. That is, exfoliate twice a week max, and stick with chemical formats — not physical scrubs, which can create micro-tears in the skin. (Check out our best practices for exfoliation.)
Step 2: Replenish with oils
Then, focus hydrating your skin and babying the barrier with gentle, restorative ingredients. As dry skin lacks oil, it only makes sense to restore what’s lacking in the form of the essential fatty acids, which fortify the skin barrier and seal in moisture. Along with fatty acids, ceramides, found naturally within skin’s barrier, are incredibly healing.
Step 3: Rethink retinoids
If your skin barrier is impaired to the point that it’s inflamed — think redness or stinging — then hold off on certain ingredients, such as retinoids. These work by speeding up cell turnover, which can further harm the skin barrier. Once you’ve got dry skin under control, you can slowly incorporate them into your routine.
Step 4: Time it right
Undoubtedly, the best time to apply these ingredients is at night: “This is when you’re going to get the most bang for your buck in terms of hydration,” says Gohara. “Skin cells are naturally regenerating at this time, so hydrating ingredients will get more depth.” In addition: “It’s a controlled environment. It’s not like you’re putting on your moisturizer and then going outside into 30 mph winds, which could get in the way of the ingredients doing their job.”
How do I treat dehydrated skin?
Step 1: Reassess your routine
First, stop whatever aggressive skin behavior landed you here to begin with — that includes over-cleansing and over-exfoliating skin. If you’re using multiple acids in your nightly routine, for instance, consider limiting it to one until you’ve figured out the source of dehydrated skin.
Step 2: Incorporate a serum
While serums are not interchangeable with moisturizer, they can still deliver moisturizing ingredients to the skin. Serums that contain hyaluronic acid, for instance, can replenish hydration in the deeper layers of skin. Layering on moisturizer afterwards will help lock that in and prevent trans-epidermal water loss.
Step 3: Take a whole-body approach
Be sure you’re treating your whole body well. Getting adequate sleep, keeping stress levels in check, and eating a nutrient-rich diet alone can’t fix your skin — but they sure do help.