You’ve probably heard some people with psoriatic arthritis (PsA) say they have less joint pain when they take gluten out of their diet. But not everyone is bothered by it.
That may leave you wondering: Is there a link between gluten and PsA?
A Closer Look
PsA is a kind of arthritis that happens in people with the skin disease psoriasis, which is also an autoimmune disease. Between 18% and 42% of people with psoriasis will go on to develop PsA.
PsA can make your joints painful and swollen and cause joint damage.
Gluten is a protein found in most bread, pasta, beer, and other foods made from wheat, rye, barley, or triticale (a mixture of wheat and rye). It can also be in things like vitamins and cosmetics.
Some people get sick when they come in contact with gluten. They may have gluten intolerance or gluten sensitivity, with symptoms like diarrhea, anxiety, abdominal pain, anemia, or headache.
Or they may have a more serious autoimmune disease called celiac disease. It can lead to intestinal damage and the inability to absorb nutrients.
People with psoriasis are three times more likely to get celiac disease, and those with celiac are more likely to get psoriasis, studies show.
Because many people with psoriasis develop PsA, some experts think there might be a link between gluten and PsA.
But it’s unclear how many people have both PsA and celiac disease. More research is needed to understand how they may be connected.
So far, it doesn’t look like you can get PsA just because you eat gluten. There’s also no reason to think you can prevent PsA by avoiding gluten.
One large study of over 85,000 people found no link between how much gluten someone ate or drank and their odds of being diagnosed with PsA.
Can a Gluten-Free Diet Help?
While it’s not recommended for everyone with PsA, there’s some evidence that a gluten-free diet may lessen severity in people who also have celiac disease, gluten sensitivity, or gluten intolerance.
The Medical Board of the National Psoriasis Foundation says avoiding gluten may help people who have both PsA and gluten intolerance or celiac disease.
But it doesn’t recommend any specific diet for PsA. It also doesn’t suggest people who have it be screened for gluten issues.
It’s unclear how many people have both PsA and gluten issues like celiac disease. More research is needed to understand ways they may be connected and whether a gluten-free diet can help.
What’s the Link?
One theory is that psoriatic disease and celiac disease share common inflammatory and genetic pathways. That doesn't prove that one causes the other.
But they both might develop because of a similar process that happens in your body. This is an area of ongoing research.
Along with celiac disease, people with psoriasis or PsA are more likely to have other autoimmune diseases. They include:
- Inflammatory bowel disease (IBD) such as Crohn’s
- Rheumatoid arthritis
- Lupus
- Multiple sclerosis (MS)
- Thyroid disease
What Are Celiac Disease and Non-Celiac Gluten Sensitivity?
These are two conditions linked to gluten intolerance. But it can be hard to tell them apart based on how they make you feel.
They share symptoms including:
- Belly pain
- Bloating or gas
- Diarrhea
- Brain fog
- Fatigue
- Joint pain
But there are some key differences between the two. For example:
Celiac disease is a serious autoimmune disease. If you have celiac disease, your immune system responds abnormally to gluten. That can lead to damage in the lining of your small intestine.
You may hear some people refer to celiac disease as a gluten allergy. But that’s not the right way to describe it, and an allergist can’t diagnose you. But you can have an allergy to wheat, which contains gluten.
Non-celiac gluten sensitivity (NCGS) is an intolerance. It’s also known as a syndrome. That means you get unpleasant symptoms when you eat gluten, but doctors don’t know why.
But it doesn’t trigger the same immune response that celiac disease does. It also doesn’t cause long-term damage.
Should You Get Tested for Celiac Disease or Gluten Sensitivity?
Probably not – but maybe, in certain circumstances.
Doctors don’t usually check for gluten issues unless there’s a good reason. And the National Psoriasis Foundation doesn’t recommend that all people with PsA get screened for gluten issues in part because those tests have a high rate of false positives.
But tell your doctor if you’re worried about a gluten intolerance or if you have a close family member with celiac disease.
You’ll need to see a gut specialist called a gastroenterologist. They’ll likely ask you some questions before they do any tests. Some examples might include:
- Do you have frequent diarrhea?
- Are you tired all the time?
- Do you have a history of iron-deficiency anemia?
- Are your PsA symptoms not responding to treatment?
Depending on your answers, you may need one or more of the following:
- Blood tests
- Biopsy of your small intestine (upper endoscopy)
- Genetic testing
- Gluten elimination diet
You may want to test for celiac disease before taking gluten out of your diet. That’s because your gut can look normal if you haven’t had gluten in a while.
As for non-celiac gluten sensitivity, there isn’t a good way to know for sure if you have it. But your doctor can rule out celiac disease or wheat allergy.
Then, they may ask you to avoid gluten products for a few months to see if you feel better.
Check with your doctor before you start a gluten-free diet. It can be hard to know which foods to leave out.
And you may not get all the nutrients you need when you change your diet. A health professional can help you safely move to a new way of eating.