This is the second part of a two-part series that reviews water-soluble and fat-soluble vitamins for psoriasis.
Psoriasis is a chronic inflammatory condition that commonly affects the skin. Approximately 1-2% of the population is impacted by psoriasis. For some patients, managing psoriasis is accomplished through topical creams, while others require systemic therapy with injections, immune modulating pills or frequent light therapy in a dermatology office.
Nutrition is one element of a patient’s life that they can control. Specifically, vitamins are cheap and easily accessible, and there is mounting evidence to show medical forms of oral vitamin A and topical vitamin D work in combination with other therapies for psoriasis.[2-4] Focusing on vitamins that have proven to be beneficial in psoriasis is one way in which people may be able to take a bit more control of their disease.
Vitamins are essential compounds in our foods that sustain us. They come in all sorts of varieties and are found in different foods. Each vitamin has a very different role to play in our bodies and each is absorbed or made by our bodies in a unique way. There are two major groups of vitamins: fat-soluble and water-soluble. The difference just represents how our bodies can absorb vitamins and get rid of the excess. This article focuses on the fat-soluble vitamins: vitamins D, A, E, K.
Vitamin D is a major vitamin associated with bone health. It regulates calcium levels and helps the body absorb calcium to maintain strong bones. It can be found in all sorts of dairy products, eggs, and a variety of meats. Sunlight is an efficient way we get enough vitamin D. However, many people may be sensitive to the sun with a risk for skin cancers, and would benefit from obtaining vitamin D from their diet instead.
One symptom of psoriasis is scaly lesions that develop on the skin since the skin cells divide too quickly. Vitamin D can combat this increase by reducing the cells from dividing too quickly. Another way vitamin D improves psoriasis is its ability to stop immune cells from making inflammation signals.[5,6] Vitamin D does this is by inhibiting a receptor on the surface of cells, called TLR-2. When TLR-2 becomes activated, it starts a pathway that results in inflammation. Vitamin D is able to reduce the signal from occurring altogether, thereby decreasing inflammation.[5,6]
Some research studies have shown that patients with psoriasis have vitamin D deficiency as well. One study showed that vitamin D was decreased in 97% of patients with psoriasis. It also seems that the more vitamin D deficient a patient may be, the worse their psoriasis may become. And even patients with psoriasis have shown improvement of their skin with vitamin D supplementation.
Vitamin D is a safe supplement and it is likely that patients are deficient in the first place. It appears safe to supplement with 2,000 IU per day, but a doctor can always measure vitamin D levels with a quick blood test! Vitamin D supplementation should be discussed with a healthcare provider to see if it is safe for you.
Vitamin A is the vitamin you probably heard about the most when you were growing up. People would likely talk about how you needed to eat your carrots to improve your eyesight. Well, they were not wrong. Vitamin A is very important for healthy vision, but it also plays a lot of other roles in the body including the function of immune cells (neutrophils, macrophages, and NK cells) and the support of human development and reproduction.[9,10] It can be found in a lot of different foods including meats and fish, brightly colored vegetables and fruits, and dairy products.
Vitamin A has a few routes to improving psoriasis, but it all revolves around inflammation. Oral medications that are very similar to vitamin A, called synthetic retinoids (acitretin, etretinate), have been studied to show vitamin A’s impact on psoriasis.[2,11,12] It turns out that acitretin decreases inflammation by decreasing factors that signal systemic inflammation.[11,12] It even prevents a special cell in the skin, the mast cell, from functioning properly. Mast cells are immune cells that play a role in psoriasis inflammation, so if mast cells are low then psoriasis may improve.
Some research has shown that psoriasis patients are deficient in vitamin A. One study showed that in psoriasis skin lesions there was a decrease in vitamin A. Another study showed that patients with psoriasis had decreased levels of vitamin A in their blood. Vitamin A has immune system functions and helps improve psoriasis, but more studies should be done to see if the majority of those patients lack vitamin A.
Vitamin A should not be supplemented without checking with a doctor first as it can have negative side effects if there is too much in the body. But it is a great vitamin to think about for a well-rounded approach to psoriasis management.
Vitamin E is best known for its antioxidant properties. This means it gets rid of harmful molecules inside cells that can damage our skin cells and other cells throughout the body. This makes it an important vitamin in various organs. Vitamin E can be found in nuts, green vegetables, and cooking oils like olive oil.
Vitamin E also decreases inflammation in the skin. A growing body of research has been done with olive oil and its anti-inflammatory effects in mice.[18-20] Alzheimer’s disease, lupus, and arthritis have all been induced in mice and the addition of olive oil was then studied. In all 3 mouse models, olive oil supplementation showed improvement of these diseases.[18-20] Olive oil is a high source of vitamin E, but there are many other sources of vitamin E with even higher amounts.
But what about psoriasis? Vitamin E supplementation, along with a few other compounds, was shown to improve psoriasis in one study. And another found decreased amounts of vitamin E in both eczema and psoriasis lesions. While vitamin E has great potential, research is ongoing to determine if it truly does improve psoriasis and other inflammatory conditions in humans.
Vitamin E is a safe supplement and can be found in a variety of foods. It has not been shown to improve psoriasis, but it does seem to impact inflammation overall.
Vitamin K is not a common vitamin many people talk about, but it has quite a number of functions. It is mostly known for creating factors in the blood to help it clot—this is vitamin K1. But there is a different type of vitamin K that has anti-inflammatory properties—vitamin K2.
In various studies, vitamin K2 decreases inflammation by stopping the production of signals that cause inflammation.[24-26] Other studies have looked at vitamin K2 in another inflammation-driven condition, rheumatoid arthritis. In these studies, vitamin K2 supplementation decreased the overall inflammation values on blood tests.[27,28] There have yet to be any studies with vitamin K on psoriasis specifically. There is an ongoing discussion about pairing vitamin K2 with vitamin D, although there is little research available on this.
Vitamin K2 is more difficult to find, but it is a safe supplement. There are no reported side effects with the most common available dosages of vitamin K2 which occur in micrograms.[29,30] More research is needed to ensure it does truly improve psoriasis.