The Link Between Body Weight and Psoriasis

Medically Reviewed by Brunilda Nazario, MD on July 07, 2021
3 min read

Staying at a healthy weight is a good idea for everyone. But it's especially important if you have psoriasis. Research shows being overweight or obese raises your chances of getting psoriasis. It can also make symptoms worse if you have it. Weight alone, though, doesn't cause psoriasis.

The link between psoriasis and excess weight isn't clear. But experts know psoriasis is an inflammatory disease. Extra fat cells release inflammatory chemicals called cytokines that may play a role in psoriasis symptoms.

Losing even a little weight can help with itchy, flaky, and sore patches on your skin and scalp. One study found that people with psoriasis who lost weight by exercising and following a low-calorie diet saw their symptoms get better by almost 50% in 20 weeks. And that was without changing anything in their medication or treatment plan.  

Slimming down may sound like a tall order, especially if you have a lot of weight to lose. But it is possible, and every little bit helps. "You can't change the fact that you have psoriasis. But you can change your weight," says Laura K. Ferris, MD, PhD, an associate professor of dermatology at the University of Pittsburgh Medical Center.

"If you have psoriasis or psoriatic arthritis, you're at a higher risk for other health conditions like heart disease and diabetes," Ferris says. Psoriatic arthritis causes joint stiffness, swelling, and other problems. People who have psoriatic diseases, including psoriatic arthritis, are at high risk of metabolic syndrome. That's a group of medical problems that includes heart disease, abdominal obesity, and high blood pressure.

But losing weight does two things to help protect you from that. "It lowers the level of inflammation in your system," says Shari Lipner, MD, PhD, a dermatologist at Weill Cornell Medicine and New York-Presbyterian Hospital in New York City. And lowering inflammation, she adds, "lessens psoriasis symptoms while greatly reducing your risk of heart disease and other serious psoriasis-related conditions."

Losing even 5 or 10 pounds can lighten the load on your joints. That's key, because up to a third of people with psoriasis get psoriatic arthritis. Losing weight may also make your psoriasis medications work better, says Ferris.

No one diet has been shown to be better for psoriasis. But dermatologists say people who take a simple approach tend to have the best results for their skin and their waistlines.

Go for fruits, vegetables, nuts, and lean protein. And eat fewer processed foods. Drink lots of water, and steer clear of alcohol and soda. "Even diet soda is linked to weight gain," says Lipner.

It may take trial and error to figure out what works for you. "Omega-3 fatty acids help with skin and overall inflammation," says Dan Ilkovich, MD, PhD, a dermatologist at Cleveland Clinic Florida. "So I tell patients that eating fatty fish like salmon is smart."

Lipner says some people have found cutting sugar out of their diet helps their psoriasis. "There's no downside to trying it," she says.

If you're not sure how to start, talk with a dietitian who specializes in skin conditions. They can help you find a diet that's right for you.

Like a healthy diet, exercise works in two ways. It makes you burn calories, which can help you lose weight and keep it off. And it eases inflammation throughout your body. Both of those things help ease psoriasis symptoms. They also reduce your chances of health problems linked to psoriasis.

If you have a lot of weight to lose or are new to exercise, "take it one step at a time," Ilkovich says. "Start by walking for 30 minutes three or four times a week."

You can even break your workouts into 10-minute chunks. Once you feel comfortable, take it up a notch by going faster or adding a new form of exercise. Try light weights or resistance exercises like push-ups and crunches.

If you have trouble slimming down, see a doctor who specializes in weight or obesity management. You can ask your primary care doctor or dermatologist for a recommendation. It's typically best to lose weight slowly over time. So be patient. And stay focused on your health rather than the scale.

"It's motivating to know that you can do more than just take medicine to improve your psoriasis," says Lipner.