It’s vital to know your vitamin D3 status when you have eczema/dermatitis. This is why.

You’ve probably heard that Vitamin D is important, but did you know that it can be critical if you suffer from eczema/dermatitis?

This is why one of the first questions I ask clients is whether they know their Vitamin D3 status. Do you know yours?

If you want to know more about how vitamin D or the lack thereof might be influencing your skin health, read on. Today’s article covers:

• What is vitamin D3 and why is it important?
• How gene variations can have an impact on your Vitamin D levels
• Vitamin D and its specific role in Atopic Dermatitis/Eczema
• How can Vitamin D help if you have dermatitis/eczema?
• How you can ensure that you are getting enough, whilst being careful to not have too much.

What is vitamin D3 and why is it important?

Vitamin D3 starts off as cholecalciferol which we, in the main, absorb through our skin through UVB or sunlight exposure. The cholecalciferol then goes through numerous processes in the liver and kidneys to become what is known as a biologically active form, or a form that our body can easily use, calcitriol. Vitamin D3 is, in fact, more of a hormone than a vitamin and it acts as a signaller to tell hundreds of genes what to do.

We have Vitamin D Receptors (VDR) throughout our body that are just waiting for the calcitriol to come and bind with them. This binding of the calcitriol and the VDR triggers a cascade of vital bodily processes via genes from bone health and calcium metabolism to inflammation and heart health amongst many others.

Vitamin D is most known for its effects on bone health as it helps calcium and phosphorus be absorbed from the gut, essential for the building and formation of strong bones. Low Vitamin D levels are linked to weak bones (Rickets) in children and osteomalacia (bone softening) in adults. (1)

Vitamin D is known to have anti-inflammatory properties, which is very useful if you are prone to inflamed skin as most eczema/dermatitis sufferers are. (2)

Vitamin D is thought to be important for heart health including hypertension and also brain health, due to the vast number of VDRs that can be found in brain tissue. (3)

How gene variations can have an impact on your Vitamin D levels

Gene variations you may have can, in some cases, impact on vitamin D availability or how responsive your receptors are to receiving the calcitriol.

If a client comes to me and says that their Vitamin D3 levels are always low, then I would suspect a genetic variant at play either on the GC gene which controls supply of Vitamin D Binding Protein (VDPR) important for transporting Vitamin D around the body or variances on the VDR gene itself, meaning that receptors are less keen to receive and bind to the circulating Vitamin D.

Another gene variation linked to Atopic Eczema is filaggrin. Vitamin D influences the production and function of skin proteins including filaggrin, so maintaining your Vitamin D levels if you suffer from atopic dermatitis is especially important.

Nutrigenomics testing can be helpful to see gene variances in relation to things like Vitamin D, inflammation or susceptibility to lactose or gluten intolerance amongst many others. I use Lifecode Gx as they provide a variety of reports that can help me unravel a great deal about an individual’s genes and how they are impacting their skin health.

Vitamin D and its specific role in Atopic Dermatitis/Eczema

Vitamin D is also vital for the growth and repair of skin cells. It supports your skin barrier, which means that it is more resistant to attacks, and it has anti-inflammatory properties that are, as I’ve already mentioned, crucial for skin conditions like dermatitis and psoriasis.

The interesting thing is that the science is clear. If you have eczema, it is very likely that your Vitamin D test results will show that you are Vitamin D deficient. Atopic Eczema sufferers specifically are more likely to be more Vitamin D deficient than the normal population. Have you tested your levels recently?

How can Vitamin D help if you have dermatitis/eczema?

Research has shown that maintaining vitamin D levels can lead to a significant reduction in eczema symptoms, especially inflammation and infection. This is especially clear in the winter months when exposure to sunlight is so much lower. Many of my clients report that their skin naturally improves in the summer months. (4)

As mentioned above, vitamin D helps keep your skin water and infection ‘tight’ thanks to its action on filaggrin, amongst other skin proteins. If your skin is ‘leaky’ you are more at risk of infection or even allowing a contact allergen to trigger a flare. A healthy skin barrier helps retain moisture as well, and we all know how much moisture a dermatitis sufferer needs to retain ! (5)

As you may have noticed throughout the article, an optimal (serum) level of Vitamin D3 is vital for health but is also critical for skin health and eczema.

Good sources of Vitamin D3 include:

• Sunlight – the best and most convenient way of getting natural vitamin D3. Get out into sunlight daily and try to get about 20 minutes sun exposure on bare skin. Ensure that you don’t stay out long enough to suffer a burn.
• Diet – foods including oily fish (salmon, sardines, mackerel, herrings etc) are good sources of vitamin D. So are fortified foods and egg yolks. The humble mushroom can also be a good source, especially if they’ve been left on a sunny windowsill where they have had their own levels boosted.
• Supplements – the recommended daily intake varies by age, health status and daily exposure to sunlight, but the UK Government recommends 100 micrograms or 4,000 IU for a healthy adult, per day during the winter months. My advice would be to check with your health or nutrition practitioner to see which dosage is best for you as an individual and to always take a break from supplementing during the summer months.

It is important to note that more is not necessarily better. Too much Vitamin D, specifically from supplementation, can be dangerous for your health. If in any doubt check with a health or nutrition practitioner and test to see where your starting levels are.

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References. ​

Charoenngam N, Holick MF. Immunologic effects of vitamin d on human health and disease. Nutrients. 2020;12(7):1–28.
Murdaca G, Gerosa A, Paladin F, Petrocchi L, Banchero S, Gangemi S. Vitamin d and microbiota: Is there a link with allergies? Int J Mol Sci. 2021;22(8):1–18.
Mirarchi A, Albi E, Beccari T, Arcuri C. Microglia and Brain Disorders: The Role of Vitamin D and Its Receptor. Int J Mol Sci. 2023;24(15).
Kim MJ, Kim SN, Lee YW, Choe YB, Ahn KJ. Vitamin D status and efficacy of vitamin D supplementation in atopic dermatitis: A systematic review and meta-analysis. Nutrients. 2016;8(12):8–17.
O’Regan GM, Sandilands A, McLean WHI, Irvine AD. Filaggrin in atopic dermatitis. J Allergy Clin Immunol. 2008;122(4):689–93.