How Diet May Improve Your Psoriasis

What the Current Science Says

Loin of Tuna and Tuna Steak
Teubner/Getty Images

It is clear that what you eat has a tremendous impact on your overall health. In recent years, there have been suggestions that diet may also help play a role in controlling the symptoms of psoriasis, an autoimmune disorder characterized by dry, itchy, and flaky skin. Although the research supporting this hypothesis is anything but conclusive, there is growing evidence that certain foods and food practices may be beneficial to people living with the disease.

Gluten-Free Diet

Like all autoimmune disorders, psoriasis is caused when the immune system suddenly and inexplicably attacks normal cells and tissues. With psoriasis, the attack spurs an inflammatory response in the dermal layer of skin which accelerates the growth of cells in the outermost epidermal layer, leading to the formation of skin patches called plaques.

There is evidence that a gluten-free diet may help temper the autoimmune assault. Gluten is a substance found in cereal grains such as wheat, rye, and barley. Celiac disease, a common autoimmune disorder, is characterized by an abnormal immune reaction to gluten, triggering gastrointestinal symptoms and, in some cases, a pustular (pus-filled) skin eruption known as dermatitis herpetiformis.

The same types of eruption are seen with pustular psoriasis, suggesting a possible link. There is even evidence that psoriasis and celiac disease are integrally linked, sharing similar disease pathways or autoantibody properties.

A 2015 study in the journal Dermatology reported that, among 218 people with psoriasis, the rate of celiac disease autoantibodies was four times higher than the general population.

Further research is needed to determine why this occurs and whether the autoantibodies found with psoriasis may be stimulated by gluten in the same way as celiac disease.

Omega-3 Fatty Acids

All autoimmune disorders are characterized by an inflammatory response. It is hypothesized that, by eating foods that are inherently anti-inflammatory, the incidence or severity of psoriasis symptoms may be relieved. After all, many of the drugs used to treat psoriasis work by tempering the immune response so that inflammation is reduced.

Much of the focus of current research has been placed on food rich in omega-3 fatty acids, such as:

  • Oily fish, like sardines, mackerel, and tuna
  • Fish oil
  • Nuts, especially walnuts
  • Seeds, like chia seeds and flaxseed
  • Soybeans and tofu

From an epidemiologic standpoint, there is some evidence to support the hypothesis. Greenland Inuits, whose diets are composed largely of oily fish, have very low rates for psoriasis and rheumatoid arthritis (a.k.a. autoimmune arthritis). By comparison, Greenland Inuits who immigrated to Denmark and adopted a meat-based diet have far higher rates.

While this may suggest a causal relationship, studies investigating the use of fish oil to treat psoriasis have been largely mixed.

A 2014 review of studies in the Journal of the American Academy of Dermatology reported that fish oil supplements can often help relieve erythema (patchy redness) in people with psoriasis but not necessarily the scaling, itching, or formation of plaques.

To this end, it is possible that Greenland Inuits have a genetic mechanism that allows them to utilize fish oil in a way that reduces inflammatory diseases. In the absence of this genetic advantage, it is unlikely that people with psoriasis will see substantial improvement by increasing their dietary intake of omega-3 fatty acids.

Low-Fat Diet

Scientists are not entirely certain why, but obesity—defined as a body mass index (BMI) of 30 kilograms per meter squared (kg/m2) or more—is associated with an increased risk of psoriasis symptoms. Many believe that metabolic syndrome, the build-up of adipose (fat-storing) cells mainly around the waist, triggers persistent inflammation which, in turn, promotes psoriasis.

A 2019 study in PLoS Medicine found that, for every 1 kg/m2 increase in BMI, there was a 9 percent increased risk of psoriasis symptoms in both children and adults.

With that being said, the scientists concluded that obesity didn't so much cause psoriasis as promote the flare of symptoms in people with a genetic predisposition for the disorder.

While it may be a bit of jump to suggest that a low-fat diet can reduce the risk or severity of psoriasis, it is known that the high intake of dietary fat (particularly saturated and trans fats) is inextricably linked to obesity and metabolic syndrome. A low-fat diet not only aids in weight loss but help decrease the overall body fat.

Furthermore, a reduced-fat diet with routine exercise appears to significantly reduce the frequency and severity of psoriasis in people with obesity.

According to a 2014 study in the British Journal of Dermatology, a 20-week weight loss plan involving diet and exercise reduced the severity of psoriasis by 48 percent in overweight or obese people who were resistant to psoriasis treatment. By contrast, a matched set of individuals counseled on diet and exercise only experienced a 25.5 percent reduction.

A Word From Verywell

Although it is too soon to conclude that any of these dietary interventions will treat or prevent psoriasis, it is clear that a nutritious diet with the right amount of healthy fats can help you achieve your ideal weight while reducing the inflammatory burden on your body. Even if things like omega-3 fatty acids don't have a direct impact on your condition, their benefits to your overall health are inarguable.

If you are unsure how to compose a safe and healthy diet, ask your doctor for a referral to a qualified nutritionist or dietitian. Avoid fad diets, quick fixes, and anything that claims to "cure" psoriasis. None of these work and may only cause you harm.

Was this page helpful?

Article Sources