Vitamins are important for maintaining normal body functions. Vitamin D is known to play a crucial role in bone health, but studies are showing that it supports healthy skin as well. Eczema (also known as atopic dermatitis) is an inflammatory skin condition that develops as a result of an overactive immune system. The condition disrupts skin-barrier function.

Vitamin D levels and skin health are connected, and studies show that supplementing your diet with vitamin D may be helpful in treating conditions like eczema. Before beginning use of any supplements, be sure to talk with your health care provider or dermatologist about which dose is right for you.

What Is Vitamin D’s Role in the Body?

Also known as calciferol, vitamin D is a fat-soluble vitamin that is important for skin and bone health. This nutrient helps the body absorb calcium in the stomach, promoting healthy bones. Vitamin D also helps reduce inflammation and promotes a healthy skin barrier, both of which are important for managing eczema. Recent research also suggests that low doses of vitamin D are associated with certain cancers and cardiovascular diseases.

This vitamin can be found in foods or taken as a supplement. The body can also make its own vitamin D when the ultraviolet (UV) rays from sunlight hit the skin.

There are two types of vitamin D — D2 and D3. Vitamin D2 (ergocalciferol) mostly comes from plants. Vitamin D3 (cholecalciferol) is made by your body or obtained from animal products like liver or fish. Both forms of vitamin D can also be taken as dietary supplements.

Vitamin D Deficiency

Levels of vitamin D in the body can be measured by a blood test that looks at the concentration of serum 25-hydroxyvitamin D. A healthy range typically falls between 20 and 40 nanograms per milliliter.

However, the National Health and Nutrition Examination Survey found that 40 percent of adults and 61 percent of children in the United States have low vitamin D levels. Those who are at an increased risk of having lower levels include people with an elevated body mass index (BMI), women, and Black Americans, according to the National Eczema Association. Reduced sun exposure due to indoor jobs, sunscreen use, and decreased consumption of vitamin D-rich foods partially explains the low vitamin D levels.

Lower serum vitamin D levels are linked to a loss of bone density, which can eventually lead to fractures and osteoporosis. In children, lack of vitamin D can cause a rare pediatric disease known as rickets, which causes bones to bend. More recently, researchers have linked low levels of vitamin D to certain cancers and cardiovascular diseases.

Vitamin D and Skin Barrier Function

The many types of cells within the skin have specific functions. For example, keratinocytes, which make up the majority of skin cells, are responsible for producing vitamin D when exposed to UV light.

Keratinocytes play an important role in repairing wounds and help maintain the skin barrier by fighting off invading pathogens. They also use vitamin D, along with calcium, to make new skin cells and repair damage. Together, these cells work with the immune system to fight and protect the body. However, when a person experiences an imbalance in keratinocyte activities, they can develop atopic eczema. Vitamin D may play a role in immune system changes and cell differentiation (the process of cells maturing into their functions), both of which can affect atopic dermatitis.

Eczema and Vitamin D Deficiency

For a long time, scientists thought vitamin D mainly played a role in bone health. However, more recent studies have found that it is involved in other processes, such as immune system regulation and new cell growth (proliferation), especially in the skin.

Now researchers believe that skin conditions, such as eczema and psoriasis, are connected with vitamin D deficiency. Because the skin barrier is disrupted in eczema, researchers have suggested that vitamin D and the cells that make it also play a role in eczema development. The link to psoriasis is more established, with topical vitamin D analogs commonly used as treatment for psoriasis.

Some studies associate lower serum vitamin D measurements with a higher risk of developing eczema, particularly in children and adolescents. Other studies found mixed results regarding the effects of vitamin D levels on the severity of eczema symptoms — for example, some findings associate lower levels with worse symptoms, and others show no connection between vitamin D levels and eczema symptoms. More research needs to be done to clarify the link.

A few factors might influence the association between lower vitamin D levels and eczema. For example, studies have found a higher prevalence of eczema in people who live in higher-latitude locations that gets less sun exposure throughout the year. The weather in these areas can also affect eczema risk.

Genetics also may play a role. Some individuals who develop eczema have changes in the genes that help break down vitamin D. As a result, these people may not create as much vitamin D compared with others, which has been found to increase the risk of severe eczema.

Does Supplementing With Vitamin D Help Treat Eczema?

Because study results show that low vitamin D levels likely play a role in the development of eczema, researchers have looked at how supplements could affect eczema symptoms.

Some researchers found that supplementing with vitamin D reduces the severity of eczema. Others reported less positive results, showing no significant improvement in symptoms with vitamin D supplementation. The topical vitamin D analogs used to treat psoriasis do not seem to help atopic dermatitis.

If you’re interested in learning more about your vitamin D levels and whether you should take a supplement, talk with your dermatology care provider. They can help determine whether vitamin D supplements would be helpful for you.

Can You Overdose on Vitamin D?

Although there are many benefits to getting extra vitamin D when your levels are low, too much of the nutrient can become harmful. The daily U.S. recommended dietary allowance (RDA) is 600 international units (IUs) of vitamin D for people aged 19 years or older. For adults over 70, the RDA increases to 800 IUs daily.

A person can develop hypervitaminosis D, or vitamin D toxicity, Ωfrom taking too high a dose of supplements. This condition develops only from supplementation, not from sun exposure or diet, because the body naturally regulates those levels.

High vitamin D levels can lead to a harmful buildup of calcium in the blood, known as hypercalcemia. This can lead to symptoms such as frequent urination, vomiting, and weakness. If you continue to consume too much vitamin D, accumulation of the mineral can cause bone pain or lead to calcium stones in the kidneys.

If you begin showing signs of hypervitaminosis D, consult your doctor. They may test your blood vitamin D levels to see if the dose you use is too high.

What Do MyEczemaTeam Members Say About Vitamin D?

Some MyEczemaTeam members have shared their experiences with taking vitamin D or other supplements to help their skin. One member said, “Started taking vitamin D and noticed that the flares are not as bad as they once were. My nights are a little more comfortable.”

Another MyEczemaTeam member shared, “So it’s been two weeks since I started vitamin D and E supplements, and I’m back to my baseline level of rash! I hope this is a real improvement.”

Meet Your Team

MyEczemaTeam is the social network for people with eczema. More than 43,000 members come together to ask questions, give advice, and share their stories with others who understand life with eczema.

Do you take vitamin D supplements to help with your eczema? What has your experience been like? Leave a comment below or start a conversation on your Activities page.