Could a healthy diet reduce rheumatoid arthritis risk?

There’s no surefire way to prevent rheumatoid arthritis (RA), a chronic inflammatory disease that can damage joints and other parts of the body. Risk factors include your sex (people assigned female at birth are at higher risk), being middle-aged or older, having a family history, excess body weight, and smoking.

You can’t change some of these things. But you can likely reduce your RA risk by quitting tobacco, making sure you’re not exposed to occupational risks like inhaled silica (which can be a hazard for people who work in construction, manufacturing, and related jobs), having good dental hygiene, maintaining a healthy weight, and being physically active. And there’s another powerful tool that may cut the risk: a healthy diet.

The authors of a May 2020 narrative review published in the journal Nutrients looked at a variety of studies investigating how different diets and types of food may affect a person’s risk of developing RA, or their symptoms once they’ve been diagnosed with RA. They suggest that a healthy dietary pattern may possibly bring down inflammation and lessen symptoms.

In particular, they found positive effects from long-term vegetarian or vegan diets, as well as polyunsaturated fatty acids (like oils from fish, flax seeds, and walnuts). Not only did these dietary interventions help symptoms, but they also slowed the progress of the disease, potentially lowering the drug dosages in treatments and improving the long-term outlook.

Another study published later that year in the journal Nutrition & Metabolism suggested that a healthy dietary pattern helps to lower the risk of RA. Researchers tested two diet types, the Western diet and a healthy diet, and found that not only did the healthy diet lower the risk of developing RA, but that following a Western diet—with plenty of red meat, processed meat, added sugar, refined carbs, and potatoes—increased the risk.

Aim for a healthy diet

Foods that are part of a healthy diet include lots of vegetables, fruits, whole grains, lean protein like fish, healthy fats (such as vegetables oils like olive or canola oil), nuts, legumes like beans and peas, and omega-3 fatty acids found in fatty fish such as salmon.

Choosing these foods means you’re opting for anti-inflammatory eating habits. Inflammation is the body’s response to infection or injury, but it can also be influenced by what you eat. Your body may react to certain foods similar to how it reacts to an infection by increasing inflammation. Too much inflammation can contribute to a variety of diseases—including RA. Some foods may help the body keep inflammation under control.

Avoid foods that may increase inflammation

You’ll want to reduce your intake of red and processed meats (like steak or deli meats). These foods are high in unhealthy saturated fats. You’ll also want to limit your alcohol consumption. Avoiding added sugars is also important.

In a 2020 narrative review published in the journal Nutrients, the authors summarized the known data from studies about RA and beverage selection. The review noted that although more research is still needed, so far studies have shown that regularly consuming sugary drinks like sugar-sweetened soda can raise the risk of developing RA, and for those who already have RA, it can negatively affect the progression of the disease. This may be particularly true for young people in their 20s and 30s.

One of the many reasons why dietary sugars, like those in sodas and juices, are harmful is that they can reduce the number of helpful bacteria in the gut. RA is an autoimmune disease, and some researchers have drawn links between RA and the health of the gut microbiome, which plays a role in regulating the immune system. These links have not yet been proven, and research is ongoing.

It’s also important to avoid other ultra-processed foods, like frozen meals, fast food, and packaged cookies and snacks. These manufactured foods account for the majority of calories eaten in the United States and almost 90 percent of our added sugars. Plus, they have been linked to higher risks of many chronic illnesses, such as heart disease and stroke.

A healthy grocery-store rule of thumb: Stick to the outside aisles, where the fresh produce and fish are. Shop sparingly in the aisles in the center, where grocers tend to stock the packaged snacks, processed foods, and sweets.