Dry skin doesn't only present as flaking. It can also show up as general redness, a tight feeling over the face, and even extra oil (it may seem counterintuitive to associate oil with dry skin, but some people's skin can produce more oil to compensate for a lack of moisture). 

But no matter what your dry skin looks like, it's pretty much always frustrating and uncomfortable. Not to mention, everyone's skin is different, so it can be hard to find which products and lifestyle changes can help your own complexion. However, there may be an unlikely culprit you might want to look into, especially if you've tried time and again to keep your skin moisturized with little to no success. Let's dive into the relationship between vitamin D and hydrated skin.* 

Here's the science behind this correlation, explained. 

Vitamin D is an essential micronutrient involved in nearly every single bodily system and function, including immune support, bone health, muscle function, and more—it only makes sense that the sunshine vitamin has a stake in the skin care game as well.* 

In fact, one randomized controlled trial in the journal Nutrients found a relationship between vitamin D insufficiency and dry skin: Researchers discovered that participants with lower vitamin D levels also had lower average skin moisture. "Our finding suggests a relationship between serum vitamin D3 levels and hydration of the stratum corneum [aka, the surface layer of your skin],"* the report reads. 

In terms of how, exactly, the vitamin affects skin health, we know that vitamin D has anti-inflammatory and antioxidant properties that help protect skin cells.* Plus, vitamin D plays a crucial role in thyroid health as it helps regulate the production of thyroid hormones.* These thyroid hormones play a key role in keeping your hair, skin, and nails youthful and strong (in addition to influencing metabolism, mood, sleep, etc.). 

And while we're on the topic of hair health: "We know that vitamin D is very important for the hair follicle and therefore hair growth,"* says board-certified dermatologist and hair care expert Raechele Cochran Gathers, M.D., on an episode of Clean Beauty School. "In fact, vitamin D is one of the fat-soluble vitamins needed for maintaining and creating functioning hair follicles."* Add that to the vitamin's roster of beauty benefits. 

You may be surprised to learn that most (93%) Americans have a dietary vitamin D gap, and many are insufficient or deficient in vitamin D altogether (41 and 29% of U.S. adults, respectively, to be exact). The best way to find out if you're lacking vitamin D is to have your doctor order a 25-hydroxyvitamin D test, which is also known as the 25(OH)D test. This is the biomarker for vitamin D status in your whole body. The optimal (not just "normal") amount you want to see, is 50 ng/ml. In some cases, even higher levels may be appropriate. The point to avoid (because it's the cutoff for vitamin D insufficiency) is 30 ng/ml. 

But it's pretty difficult to cross that 50 ng/ml threshold (and maintain it for life) without vitamin D supplementation.* Supplementation can help keep your vitamin D levels steady, no matter what time of year it is and how much sun you get in your daily life.* Double-board-certified integrative medicine doctor Amy Shah, M.D., said it best in her review for mbg's vitamin D3 potency+: "Achieving vitamin D sufficiency isn't a seasonal need; it's a daily endeavor." 

So if you've hit a wall trying to restore moisture in your skin, a high-quality vitamin D supplement can help give your skin the final hydration nudge it needs.* Not to mention, our vitamin D3 potency+ supplement also contains organic and virgin avocado, olive, and flaxseed oils, all of which support skin health as well.* In fact, one user even considers it her "secret weapon for radiant skin."* As she writes in a personal review: "I've been taking mbg vitamin D3 potency+ every night for about two months now, and it has made a massive improvement in my skin's clarity and hydration—even compared to the vitamin D3 supplement I was taking before."*

If you've tried to hydrate your skin without success, you might want to check your vitamin D levels. Luckily, vitamin D insufficiency is 100% fixable with a targeted daily supplement, and an effective formula can help fill that dietary gap, as well as provide other benefits to your skin and overall health.*