Diet for rheumatoid arthritis: what to eat and what does not help

How can diet help if I have rheumatoid arthritis?

Rheumatoid arthritis is an autoimmune disease. The immune system attacks the lining of the joints and causes inflammation. It leads to pain and swelling, especially in the fingers, wrists, elbows, shoulders, hips, knees and ankles. It also causes stiffness on getting up and, if it is not controlled, loss of mobility. It is more common in women.

It should not be confused with osteoarthritis, which is wear and tear of the cartilage. They share joint pain, but little else. See “Osteoarthritis and diet”.

Diet does not treat rheumatoid arthritis or replace the medication prescribed by your rheumatologist. It can help you look after your weight and muscle, support your treatment and avoid factors that worsen the outlook. It does less than the internet promises, but more than it might seem.

Is there a diet for rheumatoid arthritis?

There is no diet with evidence behind it, and it is worth saying this upfront because many diets circulate. The review that informed the European rheumatology society EULAR’s lifestyle recommendations examined foods, nutrients, supplements and whole diets.

Its conclusion is that no dietary intervention has substantial benefits for rheumatoid arthritis or osteoarthritis [1]. It found small effects, such as the effect of fish oils on pain, which are probably of little practical relevance [1].

Signs of benefit come from prevention studies. An analysis of six studies found that people who follow the Mediterranean diet more closely develop rheumatoid arthritis somewhat less often, by around 16 % [4]. This is an association and concerns the risk of developing the disease. Once the disease is present, studies of the Mediterranean diet are few and of very low quality [1].

Even so, this is the dietary pattern we recommend: the one in our anti-inflammatory eating guide. It supports overall health (weight, muscle and heart health) and is the pattern most people can sustain. You could try it for three months and discuss how you feel with your care team.

A day of meals with rheumatoid arthritis

The foods from the lists above, spread throughout the day, with nothing crossed off. An ordinary day could look like this.

• Breakfast. Wholemeal bread with tomato and extra virgin olive oil, and an egg or plain yoghurt. Coffee or herbal tea.
• Mid-morning. A piece of fruit and a handful of walnuts.
• Lunch. Salad or vegetables to start, lentils with pumpkin and carrot, and fruit.
• Afternoon snack. Plain yoghurt with fruit, or toast with cheese.
• Dinner. Vegetable purée and oven-baked mackerel or sardines with potato.

There are no gram amounts or calories on purpose: this is an example to guide you. What makes it manageable is the shopping. With tinned pulses, frozen vegetables and a tin of oily fish in the cupboard, you can get through a flare day without cooking.

Do eggs, tomatoes or citrus fruits make arthritis worse?

There is no basis for cutting them out unless a diagnosis calls for it, and this is what we are asked about most in consultations. Elimination diets have been studied in rheumatoid arthritis, from liquid and allergen-free diets to ketogenic, vegetarian and vegan diets. According to the EULAR review, they did not improve most of the outcomes assessed, including pain, mobility, swollen joints, inflammation in blood tests and morning stiffness [1].

The cost of removing foods, on the other hand, is well known. Every food group you cut out makes your diet poorer, more expensive and harder to maintain. Some people end up with a growing list of foods they have removed, and shared meals become a problem. If you suspect that a food does not agree with you, the next step is to get a diagnosis (coeliac disease, lactose intolerance or an allergy) before removing anything.

Does omega-3 help? What about vitamin D or probiotics?

Omega-3 is the only one with some evidence behind it, and that evidence points to a small effect. Fish oils slightly improved pain, with moderate-quality evidence [1]. For this reason, we do not recommend omega-3 supplements to treat arthritis. A practical option is to include oily fish, walnuts and the flaxseeds from the list in your meals.

In rheumatoid arthritis, probiotics, vitamin D and fish oils showed no effect or an effect of little practical relevance [1].

Any supplement should be prescribed by your doctor or dietitian-nutritionist. If you take anticoagulants or antiplatelet medicines, talk to your doctor before using omega-3 capsules.

What matters more than food

EULAR’s lifestyle recommendations have a section devoted to three things [2]. The first is weight. They recommend reaching and maintaining a healthy weight, with the person and their healthcare team working together [2].

If you have weight to lose, the approach is in our guide to losing fat and keeping it off; here, what changes is the pace. If you are underweight, or have lost your appetite and are losing muscle, that can also be addressed. First, your doctor rules out another cause, and then we can help as dietitians supporting weight gain.

The second is smoking. People who smoke should be supported to quit [2]. The third is exercise. It is safe and improves pain and disability, especially in osteoarthritis and axial spondyloarthritis [2].

There is a fourth factor related to diet: alcohol. The WHO says there is no safe amount of alcohol for health: the less, the better; and none during pregnancy, while breastfeeding, in childhood, before driving or if your medication does not allow it. In rheumatoid arthritis and gout, even moderate drinking can be associated with flares [2].

With psoriasis, the psoriasis diet guide explains what is worth changing in what you eat.

If eating is the difficult part

There are three common problems with this disease that no diet takes into account, and we see them in consultations every week.

Your hands. Opening a jar, peeling, chopping or draining food can be impossible on a flare day. Tinned pulses, pre-chopped frozen vegetables and easy-open tins can help.

Dry mouth. Some people with rheumatoid arthritis also have Sjögren’s syndrome, which causes low saliva production. Swallowing can then be difficult, and tooth decay is more common. Moist foods, mild sauces, sipping drinks during meals and more frequent dental check-ups can help.

Your stomach. Anti-inflammatory medicines taken for a long time, especially together with corticosteroids, can lead to gastritis or an ulcer . If this applies to you, our advice is in the gastritis eating guide. Your doctor will adjust your medication.

What mistakes do we see most often in consultations?

Starting with a list of foods to cut out. This is the approach most people give up on. First, add vegetables, pulses, fish and fruit. Once that is in place, consider whether anything needs to be reduced.

Expecting food to do the job of medication. Delaying or reducing treatment because “I’m eating better now” is the decision that costs the most. Your rheumatologist decides on any treatment changes.

Looking for the food that caused a flare. Flares come and go on their own. Almost anything you do before one settles will seem to have worked. That is why lists of foods to avoid keep growing and are never emptied.