9 Foods That May Make Psoriasis Worse

by Claire Gillespie Health Writer

We may not have a definitive scientific link between diet and psoriasis, but there are studies to back up theories that certain foods may trigger flares. Psoriasis isn’t simply a skin problem: it’s a chronic, inflammatory disease, and many people say they manage it better if they avoid inflammatory foods. However, never cut out any major food groups or make any significant dietary changes without checking with your doctor first.

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Red meat

Red meat contains a polyunsaturated fat called arachidonic acid, which can easily convert into inflammatory compounds and may exacerbate psoriasis symptoms. (The same goes for processed meats like sausage and bacon.) A study published in Alternative Medicine Review showed that reducing red meat intake, along with other dietary guidelines like eating minimal protein in general and increasing certain fruits and vegetables, can supplement other treatments for psoriasis.

Fresh eggplants.
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Nightshades

Fans of white potatoes, tomatoes, peppers, and eggplant, brace yourselves: these “nightshade” foods may trigger psoriasis flares. A survey of about 1,200 people with psoriasis, published in Dermatology and Therapy in 2017, found that 51 percent of patients managed to improve their symptoms by reducing their nightshade consumption. If cutting out all nightshades is too much for you, try eliminating one at a time and record the results.

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Gluten

The National Psoriasis Foundation supports the theory that people with psoriasis may have an increased sensitivity to gluten, a protein composite found in wheat, barley, rye, oat, and other cereal grains. In the Dermatology and Therapy survey of psoriasis patients, 53 percent saw skin improvement by eliminating gluten. While more research is required, the likely theory is that when the body recognizes gluten as a foreign invader, it forms antibodies, which initiate an inflammatory response.

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Junk food

If you eat junk food, you can’t get away from saturated fats, trans fats, and refined starches and sugars. All of these can promote inflammation, making junk and processed foods (including soda) a potential danger for people with psoriasis. Another risk of junk food is that it is high in calories with little or no nutritional value. A higher risk of heart and vascular problems goes hand-in-hand with psoriasis, and being overweight adds to that risk.

Soy in bowl and on spoon.
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Soy

If you eliminate cow’s milk to help manage your psoriasis, you may be tempted to drink soy milk instead. However, soy and soy oil contain high levels of omega-6 fatty acids, which promote inflammation. While there’s no evidence that soy products trigger psoriasis, this may be the case if you are sensitive to soy. Soy also contains estrogen-like compounds, and excess estrogen has been linked to systemic inflammation.

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Condiments and spices

If you think that your psoriasis flares after eating spicy meals, there might be a reason for that. Some people with psoriasis find condiments and spices to be dietary triggers. Most likely to cause trouble for people with psoriasis are pimento, cinnamon, curry, and paprika. Condiments like vinegar, mayo, Tabasco sauce, Worcestershire sauce, and ketchup may also cause problems, because they contain inflammatory substances.

Dairy products.
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Dairy

Like red meat, dairy products contain the natural inflammatory arachidonic acid. Cow’s milk may be the dairy product best avoided if you have psoriasis, as it also contains the protein casein, which has been linked to inflammation. (Egg yolks are also high in arachidonic acid.)

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Alcohol

Several studies have linked alcohol to psoriasis flares, and that darker drinks in particular are more likely to have an adverse effect. Further research is needed, but if you do drink, doctors advise only moderate drinking (for men, no more than two drinks a day, and for women, no more than one). If you take certain psoriasis medications, like methotrexate or acitretin, your doctor may recommend that you stay away from alcohol completely.

Citrus fruits.
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Citrus fruits

A psoriasis flare may be triggered by an allergic reaction, and citrus fruits like oranges, grapefruit, lemons, and limes are a common allergen. It’s not clear what the connection between citrus fruits and psoriasis is, but it may be something to do with Vitamin C content. Vitamin C can boost the immune system and make the autoimmune response worse. If removing citrus fruits from your diet helps manage your psoriasis, cut out their derivatives (like lemonade and grapefruit juice) too.

Claire Gillespie
Meet Our Writer
Claire Gillespie

Claire Gillespie writes about mental health, psoriasis, psoriatic arthritis and IBS for HealthCentral. She is a passionate about mental health awareness, and also writes about health and wellness for other sites, including Vice, SELF, Zocdoc, Reader’s Digest, and Healthline. You can follow her on Twitter @southpawclaire.