Dear Doctor: I’ve had psoriasis for close to seven years, and lately it has been flaring up more often. Is there anything I can do with my diet to control this, or even prevent it from happening?
Dear Reader: That’s a good question. Thanks to the growing body of research detailing the link between inflammation and chronic disease, there are some equally intriguing answers. To explore it further, let’s start with what psoriasis is.
When you have psoriasis, your immune system has gone a bit haywire. It’s sending faulty danger signals that cause skin cells to grow at 10 times their normal rate. That’s much faster than your body can process and shed them, and the result is raised and itchy patches of red skin, often covered with silvery scales. Typically, these appear on the knees, elbows and scalp, but may also be present on the palms of the hands, soles of the feet and along the torso.
Although there is a complex genetic component to psoriasis, environmental factors are also at play. Stress, infection, certain medications, smoking and alcohol use have all been shown to be potential triggers for flare-ups.
The results of that research we mentioned make it increasingly clear that inflammation is a factor in many chronic and degenerative diseases, including heart disease, diabetes and many cancers. Since inflammation plays a significant role in psoriasis, a lot of attention is now being paid to your question of whether diet may affect the disease.
Due to the way psoriasis behaves, drawing conclusions can be difficult. Flare-ups are followed by periods of dormancy, which give way again to subsequent flare-ups. Since the nature of the disease is to fluctuate, connecting the dots between a specific dietary or behavioral change, and the absence or presence of flare-ups, is a challenge.
Still, scientists are beginning to find answers. In studies of psoriasis patients whose diets included fish oil supplements to add omega-3 polyunsaturated fatty acids, a measurable number of participants reported fewer and less severe flare-ups. When they stopped following the diet, the benefits also waned.
Gluten sensitivity may also play a role. In a study of individuals with antibodies to gliadin, one of the proteins that are present in wheat, following a gluten-free diet lessened psoriasis symptoms. When gluten was reintroduced to the diet, flare-ups became more frequent.
If you’re interested in modifying your own diet, the National Psoriasis Foundation offers some guidelines. Foods to add to your diet include leafy green vegetables and colorful fruits such as spinach, kale, broccoli, squash and blueberries. Foods that are a natural source of omega-3 fatty oils are also on the list. They include cold-water fish, olive oil, walnuts and pumpkin seeds.
The foundation recommends that people with psoriasis avoid processed foods, refined sugar and fatty red meat. Research shows that maintaining a healthy weight is important as well.
The idea is that when you have an inflammatory disease, steering clear of foods with inflammatory effects can help. Whatever the outcome, the result is a more healthful diet.
Eve Glazier, M.D., MBA, is an internist and assistant professor of medicine at UCLA Health. Elizabeth Ko, M.D., is an internist and primary care physician at UCLA Health.