A range of treatments are available for psoriasis, from skin ointments to drugs that alter your immune system. But can easing the symptoms of this common condition be as simple as changing the foods we eat?

For the more than 8 million people in the U.S. who live with psoriasis, diet may play a bigger role than we think in how our bodies handle inflammation. Margaret Wesdock, a registered dietitian at Johns Hopkins Medicine, offers insight on which foods to eat and which to avoid if you have psoriasis.

What is the relationship between psoriasis and your diet?

Psoriasis is a chronic (long-term) autoimmune skin disorder. “The body mistakenly attacks its own tissue,” explains Wesdock. “It starts overproducing skin cells, which lays down plaques on your skin.” Plaques are red, scaly patches that can be itchy or painful. Sometimes psoriasis is accompanied by psoriatic arthritis, an inflammatory joint condition.

Neither of these conditions is caused by anything you eat, but there’s an important link between your diet and psoriasis. Many foods are known to cause inflammation throughout the body. In some people, this widespread irritation can make the symptoms of psoriasis worse.

How do foods cause inflammation?

Studies are ongoing about how certain foods trigger an inflammatory response. Research suggests that some foods, especially highly processed ones, put your body’s defense mechanisms into overdrive.

For example, fatty foods can increase inflammation in adipose tissue (body fat), which is throughout your body. Ongoing fat tissue inflammation (common in people who are overweight or obese) greatly increases your risk of psoriasis. It also increases your risk of type 2 diabetes, heart disease and other chronic health conditions.

Foods to Avoid With Psoriasis

Many of the same high calorie foods that can lead to weight gain and increase the risk for obesity, diabetes and heart disease are also inflammatory. There are several categories of inflammatory foods that can make psoriasis symptoms worse.

Alcohol

Excessive alcohol consumption makes your liver work overtime. It has to produce chemicals to metabolize the alcohol, which can lead to long-term inflammation if you drink heavily or regularly. Alcohol can also damage the good bacteria in your gut, which can lead to inflammation in your colon and intestines.

Dairy

Many dairy products tend to be high in fat, which can lead to inflammation. Products that contain cow’s milk also contain casein, a protein that some people have trouble digesting. People who are lactose intolerant don’t have enough of the digestive enzyme lactase. Chronic gastrointestinal irritation from these conditions can make inflammation worse. For some people, psoriasis symptoms improve when they cut dairy from their diet.

Foods containing refined carbohydrates

Refined carbohydrates are highly processed (think white bread, white rice, pasta, pastries and some breakfast cereals). They’ve been stripped of fiber and whole grains and tend to contain a lot of sugar, which can cause your blood sugar to spike. Refined carbohydrates also increase advanced glycation end products, which are substances in your blood that can lead to inflammation.

Foods with saturated fats and trans fats

Fats in red meat, cheese, fried food, margarine, fast food and many processed snacks are known to trigger inflammation in the body. These fats increase the amount of low-density lipoprotein (LDL) in your blood, also called “bad cholesterol.” Studies suggest there may be a link between excess fat in the body and development of psoriasis and worsening of psoriasis symptoms.

Foods high in added sugar

Added sugars in soda, fruit juices, candy, baked goods and other sweets are different from natural sugars in food such as fruit. Our bodies produce insulin to process sugar, but too much added sugar forces our bodies to store that extra energy in fat cells and inflame the fat tissue. Foods with lots of added sugars can also lead to increased levels of inflammatory proteins called cytokines. Some studies suggest that artificial sweeteners such as aspartame may also lead to chronic inflammation.

Foods that contain gluten

Research suggests that people with psoriasis tend to have higher rates of celiac disease. In people with celiac disease, gluten (a protein in wheat and some other grains) triggers an autoimmune response that causes the body to attack tissues in the small intestine. People with celiac disease need to avoid gluten completely, though some people without the disease have found that reducing gluten in their diet lessens psoriasis flare-ups.

How can you measure inflammation in the body?

While certain foods are known to cause inflammation, not everyone reacts the same way to these foods. “I’ve had some patients who felt that wheat was making their psoriasis worse. Another patient noticed more flare-ups when she ate nuts,” says Wesdock.

Some tests can measure inflammation with biomarkers, which are substances in your blood that spike when your body reacts a certain way to foods such as fats or sugar. For example, a simple test can check for increased levels of C-reactive protein (CRP) in your blood. The liver makes extra CRP if there’s inflammation in your body. Doctors might use this test to determine how likely you are to develop a chronic condition like heart disease.

As you adjust your diet to ease psoriasis symptoms, be sure to work with your psoriasis doctor to monitor symptoms and inflammation levels.

Foods to Eat if You Have Psoriasis

Just as some foods trigger inflammation, others can help combat inflammation. In general, having a balanced whole-foods diet is the best approach to reduce inflammation throughout the body. It may reduce psoriasis flare-ups or make your symptoms less severe. Following a Mediterranean diet for psoriatic arthritis or psoriasis can also reduce chronic inflammation that contributes to heart disease, type 2 diabetes, cancer and other conditions.

The best foods if you have psoriasis include:

• Fish, lean protein or plant-based proteins such as tofu or tempeh
• Fruits and vegetables
• Legumes (beans and lentils)
• Nuts and seeds
• Olive oil
• Small amounts of low-fat dairy
• Whole grains

There’s no evidence that vitamins or supplements help ease psoriasis symptoms. The best way to get all the vitamins and minerals you need is from the foods you eat. But it’s generally safe to take a daily multivitamin. Talk to your doctor or a registered dietitian about other supplements that might be right for your needs.

How can I get started with a psoriasis diet?

If you’re going to change your diet to combat psoriasis, Wesdock recommends starting slowly. Jumping into a highly restrictive diet isn’t usually sustainable and may deprive you of important nutrients. Instead, start by cutting out some highly processed foods.

Substitute the pastries and cookies with fresh fruit. Opt for herbal tea or water flavored with fresh fruit, mint or cucumber. If you think there’s a specific food or ingredient that’s triggering psoriasis flare-ups, talk to your doctor or a registered dietitian.

Being overweight or obese can also make psoriasis worse, so you may want to start a weight loss plan that includes fewer calories and smaller portion sizes. Any psoriasis treatment diet should be accompanied by healthy lifestyle choices. Get plenty of sleep and regular exercise, and try to reduce stress in your life. If you smoke, talk to your doctor about a plan to quit.