There may be links between vitamin D and psoriasis. Some research suggests that low levels of vitamin D can trigger the immune system. It is possible that boosting vitamin D levels may help reduce symptoms of psoriasis.

Vitamin D, also known as the sunshine vitamin, is very important for maintaining and supporting the health of bones, teeth, the immune system, and other parts of the body, including the skin. As such, scientists have found links between vitamin D and some skin conditions, including psoriasis.

This article will look at the relationship between psoriasis and vitamin D, how to get more vitamin D, and whether or not an extra dose of this vitamin can help people with psoriasis.

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Vitamin D plays a role in many bodily functions. Research indicates that this includes different roles in the proper functioning of the skin, including an involvement in inflammatory skin conditions, such as psoriasis.

Evidence notes that low vitamin D levels are common among people with long-term psoriasis. At present, the precise role of vitamin D in psoriasis is unclear. Some individuals with psoriasis may have lower levels of vitamin D due to a number of factors, such as covering their skin to decrease sunlight exposure.

However, other evidence suggests that low levels of vitamin D may trigger the immune system and could result in the development of conditions such as psoriasis. Vitamin D may also influence keratinocytes in the skin, which are the most abundant cell in the outer layer of the skin. Low levels may cause these cells to proliferate and lead to the development of thick, scaly plaques that are a common symptom of psoriasis.

While further research is still necessary to understand the connection between vitamin D and psoriasis, it may be possible that low vitamin D levels may favor the development of psoriasis. As such, many treatments for psoriasis may include vitamin D, or similar substances, to treat and reduce symptoms.

Below are some ways that people living with psoriasis can attempt to boost their vitamin D levels.

Food

Good dietary sources of vitamin D can include:

  • cod liver oil
  • oily fish, such as trout, salmon, and mackerel
  • fortified cereals, juices, and dairy produce
  • egg yolk

A person’s diet can provide a safe source of vitamin D, with most people getting sufficient vitamin D through a healthful diet and careful exposure to the sun’s UVB rays. The Office of Dietary Supplements (ODS) suggests a daily value for vitamin D as 20 micrograms (mcg) or 800 international units (IU). A tablespoon of cod liver oil or 3 ounces of trout provides 1,360 IU and 645 IU, respectively.

Sunlight

The sun enables the body to produce vitamin D. However, sunlight can result in damage to the skin and may increase the risk of skin cancer. For this reason, sunlight exposure may not be an advisable treatment for everyone with psoriasis. People with psoriasis should ask a doctor for advice before increasing their exposure to sunlight.

Similarly, tanning beds are not suitable for treating for psoriasis because they may also increase the risk of skin cancer and other skin problems. People with psoriasis should not use a tanning bed.

Instead, a healthcare professional may suggest UVB treatment as an option.

UVB light therapy

Light therapy, or phototherapy, is a treatment that uses UV light to reduce swelling and slow the excessive skin cell production that psoriasis causes. While there are many different types of light therapy available, practitioners most often use UVB light therapy to treat psoriasis.

While this option uses UVB rays, which triggers the production of vitamin D in the skin, it may be other factors rather than the additional vitamin D that improves symptoms of psoriasis.

Click here to learn more about phototherapy at home.

Supplements

Vitamin D supplements are available in 2 forms: vitamin D2 and vitamin D3. Plants and fungi produce vitamin D2 and animals, including humans, produce vitamin D3. A doctor may recommend supplements for those who may be at risk of a deficiency, such as those living in areas with limited sunlight or people with limited sun exposure due to being inside most of the time.

A 2022 case series suggests that oral vitamin D supplementation could offer complete remission of psoriasis without any adverse events. It indicates that taking doses of vitamin D3 ranging from 30,000–60,000 IU over a period of 2–6 months, followed by a lower daily maintenance dose could control symptoms of psoriasis.

It adds that a supervised, daily oral supplement could be given safely as an effective treatment for psoriasis. However, more research is necessary to determine the efficacy, optimal dosing, and any adverse effects of vitamin D administration in people with psoriasis. There is currently no specific recommendation for adults to use vitamin D supplements. Anyone with psoriasis who is considering supplements should speak to a doctor first.

Medication

A doctor may prescribe creams and other topical applications containing a synthetic form of vitamin D, known as analogues, to treat the symptoms of psoriasis. These vitamin D like chemicals are typically safe options that people can continue using long-term, alongside other treatment options, and often include calcipotriene and calcitriol as active ingredients.

Some studies have found that applying vitamin D to the skin, especially combined with corticosteroids, might be an effective treatment. To reduce the risk of side effects, a person should apply a thin layer once or twice daily and should not exceed a 200 gram dose a week. A doctor may also advise taking small breaks between topical treatments to allow the skin to recover.

People with psoriasis often have low levels of vitamin D, but the reason is unclear. Low levels of vitamin D can result from:

  • poor diet
  • low absorption or high excretion, due, for example, to inflammatory bowel disease
  • lack of exposure to sunlight
  • certain medical conditions

In addition, people are more likely to have a deficiency if they:

  • are older in age
  • have a high BMI
  • are breastfed infants
  • have dark skin
  • have little exposure to the sun, due, for example, to winter cloud cover, an indoor lifestyle, or wearing clothing that covers all the body

If there is a chance that a person has low vitamin D levels, a doctor can use a blood test to check. If the levels are low, they may advise the person to take oral supplements to increase their levels.

According to the ODS, taking too high a dose of a vitamin D supplement can lead to:

  • loss of appetite
  • excessive urination
  • irregular heart beat
  • high calcium levels in the blood, increasing the risk of kidney stones and cardiovascular problems

Before altering the diet, or using any supplements, it is advisable for a person to consult their doctor. They will be able to provide guidance and help prevent any adverse effects and interactions with other drugs.

At present, there is not much evidence to suggest that other vitamins or supplements may help reduce symptoms of psoriasis.

However, oily fish are a good source of vitamin D, and some people with psoriasis believe that omega-3 fatty acid supplements can help ease their psoriasis. Omega-3 fatty acids may reduce inflammation, which suggests it could help with inflammatory conditions, such as psoriasis.

Currently, however, there are not enough long-term clinical trials to show whether these supplements are effective for treating psoriasis.

Some evidence suggests there may be a link between vitamin D and psoriasis. Research indicates that vitamin D may influence inflammatory conditions, such as psoriasis, and people with the condition often have low levels of vitamin D. Many treatment options for psoriasis also use analogues of vitamin D or help supply the body with sufficient levels.

However, scientists do not yet understand how the two interact and more research is necessary to determine if increasing vitamin D levels is beneficial. Before making any changes to their lifestyle to increase vitamin D, it is advisable for people to consult their doctor about possible options.

Sources:

Barrea, L., et al. (2017). Vitamin D and its role in psoriasis: An overview of the dermatologist and nutritionist. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5486909/

Calcipotriene ointment. (2020). https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=1bc020e0-b5ae-4cda-aa5b-87fa0452a6bc

Calcitriol ointment. (2020). https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=7fa4ab07-3d8e-4300-91f3-b1e17cba8691

Dietary modifications. (2020). https://www.psoriasis.org/dietary-modifications/

Does light therapy (phototherapy) help reduce psoriasis symptoms? (2017).
https://www.ncbi.nlm.nih.gov/books/NBK435696/

Filoni, A., et al. (2018). Association between psoriasis and vitamin D. https://journals.lww.com/md-journal/Fulltext/2018/06220/Association_between_psoriasis_and_vitamin_D_.68.aspx

Ghiasvand, R., et al. (2017). Indoor tanning and melanoma risk: Long-term evidence from a prospective population-based cohort study. https://academic.oup.com/aje/article/185/3/147/2893688

Maestro, M. A., et al. (2019). Vitamin D and its synthetic analogs. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6727385/

Mahtani, R., et al. (2022). Daily oral vitamin D3 without concomitant therapy in the management of psoriasis: A case series. https://www.sciencedirect.com/science/article/pii/S2772613422000014

Phototherapy. (2021). https://www.psoriasis.org/phototherapy/

Psoriasis treatment: Phototherapy. (n.d.). https://www.aad.org/public/diseases/psoriasis/treatment/medications/phototherapy

Psoriasis treatment: Synthetic vitamin D. (n.d.). https://www.aad.org/public/diseases/psoriasis/treatment/medications/synthetic-d

Umar, M., et al. (2018). Vitamin D and the pathophysiology of inflammatory skin diseases. https://www.karger.com/Article/Fulltext/485132

Vitamin D. (2022). https://www.hsph.harvard.edu/nutritionsource/vitamin-d/

Vitamin D: Fact sheet for health professionals. (2021). https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/