Many people struggle to maintain a healthy body weight. But for those with psoriatic arthritis (PsA), joint pain can make weight management seem even more difficult. Members of MyPsorasisTeam have expressed challenges with their weight, including one member who shared: “Because of the combination of PsA, direct joint changes, and all the secondary effects from steroids, I really struggle with weight issues. I had a food issue before PsA but was always able to exercise it into submission. I considered bariatric surgery but can only imagine what a PsA body could do with that recovery period.”

Finding the motivation to be physically active when dealing with a PsA flare-up isn’t always easy. However, research indicates several reasons why people with PsA may benefit from being mindful about their weight.

Another member echoed the importance of weight management: “I have had PsA for more than 50 years, and it gets worse over time. Plus, my extra weight doesn’t help. I would say to anyone with PsA, try to keep your weight down.”

Not only does excess body weight put more pressure on the joints, but obesity also promotes a state of chronic inflammation and can impair the effectiveness of some arthritis medications. Read on to find out what research has to say about the connection between body mass index (BMI) and inflammatory joint disease.

Does Weight Gain Cause Psoriatic Arthritis?

High inflammation levels are a characteristic sign of all autoimmune diseases. Excess adipose tissue contributes to low-grade inflammation and may cause hormonal changes that raise the risk of conditions like PsA. For example, C-reactive protein is one of the several inflammatory biomarkers elevated in people with obesity and PsA.

About 25 percent of people with psoriasis experience joint issues. The exact cause of PsA remains unclear. Still, epidemiological studies suggest that people with a BMI over 35 have a 2.69 higher relative risk of developing psoriasis than those with a lower BMI.

The link between PsA and obesity has started to become apparent based on the results of multiple studies. For example, one study’s data suggested that overweight individuals had a 1.83 higher relative risk of developing PsA than those in the normal weight category. The risk increased along with weight, going up to 3.12 for those with obesity and 6.46 for those with a BMI over 35.

Another similar study in the United Kingdom looked at PsA incidence in 75,000 participants with psoriasis. Here, the likelihood of developing PsA also increased incrementally for those with higher BMIs.

Understanding BMI

BMI is calculated by dividing body weight in kilograms by height in meters squared. There are several free calculators online, or you can ask your doctor what your BMI is.

The different BMI categories are as follows:

• BMI under 18.5 — Underweight
• BMI between 18.5 and 24.9 — Normal weight
• BMI between 25 to 29.9 — Overweight
• BMI of 30 or greater — Obese

Although BMI can be an unreliable measurement for some individuals (such as those with a high percentage of muscle mass), for the general population, BMI can be an accurate tool for characterizing overweight or underweight individuals. Other measurements, like skinfold thickness or waist circumference, can also help your doctor identify whether you have more than the optimal amount of body fat for your frame.

How BMI Affects PsA Severity and Treatment

People with any form of inflammatory arthritis (including rheumatoid arthritis and PsA) may find that losing just a few extra pounds can make a big difference in their quality of life. Studies show that every pound of body weight puts four pounds of pressure on the knees. That means bringing your weight down by 10 pounds can feel like 40 pounds have been lifted from your joints. Not only will you likely be able to move more freely, but you may prevent some of the permanent cartilage damage that progresses more quickly when carrying extra weight.

It can be challenging for health care providers to find treatment strategies for individuals with PsA who are obese, as obesity is known to diminish the response to anti-TNF (tumor necrosis factor) biologics and some disease-modifying antirheumatic drugs (DMARDs). The dosages of intravenous Stelara (ustekinumab), Remicade (infliximab), and Simponi (golimumab) are currently adjusted based on body weight. However, higher doses of other PsA therapies don’t appear to resolve efficacy issues in people with obesity, so standard doses are given. Early findings suggest that DMARDs, including Orencia (abatacept), tocilizumab, or rituximab, may be preferable to anti-TNF agents for people with obesity. But more research is needed before specific recommendations can be made.

Being overweight with PsA can also pose an increased risk of metabolic syndrome and comorbidities like type 2 diabetes, cardiovascular disease, and gout. Although it may feel like an extra effort, keeping your BMI under control can often end up making life with PsA easier in the long run.

Can Losing Weight Help?

If you’re overweight and have PsA, losing a few pounds may offer benefits. Weight loss isn’t a guaranteed cure, but it increases the likelihood that you’ll be able to reach a level of minimal disease activity or remission from PsA symptoms. Losing weight has been shown to increase the effectiveness of prescription PsA therapies. When your joints are less stiff and painful, you may find physical activity more enjoyable, making it easier to maintain a healthy weight through that means.

What You Can Do

A combination of exercise and healthy eating can help contribute to a healthy lifestyle, especially for people with PsA. But that doesn’t mean you need to overdo it. For example, one member of MyPsoriasisTeam said: “I had to start really slow and work up, little by little. The more I did, the better I got. If I stopped for a period of time, I could tell that I was starting to get stiff again. I set daily goals and try to meet them. Doing something is far better than nothing. You don’t have to kill yourself to see results.”

In addition, eating healthy doesn’t need to be complicated. The Academy of Nutrition and Dietetics recommends simple tips for weight loss, including:

• Avoiding added sugars and solid fats
• Choosing whole grains over refined grains to get more fiber
• Opting for seafood, lean meats, and beans for protein instead of fried foods or processed meats that are high in saturated fat
• Satisfying a sweet tooth with whole fruits
• Staying away from sugar-sweetened beverages (and drinking more water)
• Watching out for oversized portions

Talk to your doctor about meeting with a physical therapist or registered dietitian for more support with exercise and nutrition. Even if you’re unable to reach an “ideal” BMI, your quality of life with PsA may still improve from moderate weight loss. Finding some relief from swollen joints and other PsA symptoms can serve as a motivator to take better care of your overall health.

Find Your Team

MyPsoriasisTeam is the social network for people with psoriatic disease. Here, more than 101,000 members from around the world come together to ask questions, offer support and advice, and meet others who understand life with psoriatic arthritis and psoriasis.

Have you noticed a connection between weight changes and how your joints feel? Do you take any actions to manage your weight as part of your psoriatic arthritis care? Share your insight in the comments below, or start a conversation by posting on MyPsoriasisTeam.