Food & Disease: How Diet May Affect Rheumatic & Musculoskeletal Diseases

EULAR 2021—Ask any rheumatologist what is among the most common questions patients ask and the answer will certainly include a variation of “Which foods should I be eating, and which foods should I avoid?” Questions surrounding pro-inflammatory and anti-inflammatory diets abound, and it can be challenging to reply to these inquiries with evidence-based responses.

During EULAR 2021, Elena Nikiphorou, MBBS/BSc, MD (Res), FRCP, PGCME, FHEA, consultant rheumatologist and an honorary senior lecturer at King’s College London, U.K., addressed this topic in a lecture on diet in rheumatic and musculoskeletal diseases.

Dr. Nikiphorou began her presentation by noting that diet undoubtedly plays a role in inflammation. Using the mosaic autoimmunity model, she described the interplay between the environmental, genetic, immunological and hormonal pathways that ultimately lead to the development of autoimmunity in patients.1 Individual dietary components sometimes play clear roles in contributing to inflammatory pathways, such as how salt intake leads to upregulation of pro-inflammatory macrophages, an increase in Th17 cell activity and interleukin (IL) 17 levels, and a decrease in regulatory T cell function.

Aside from pro- and anti-inflammatory features of various foods, a healthy diet can help reduce body mass index (BMI) and prevent the onset of comorbidities, such as cardiovascular disease and osteoporosis, which can complicate matters for patients with rheumatic disease.

Diets

A typical Western diet often includes high levels of refined carbohydrates, salt, sugar and omega-6 fatty acids, and low levels of fiber and long-chain omega-3 fatty acids, Dr. Nikiphorou said. Good sources of omega-3 fatty acids include olive oil, soybean oil, flaxseed oil, sardines, mackerel and salmon. Unfortunately,many of these healthy foods are lacking in the diets of most Americans.

The intake of sugary beverages may, on its own, be a risk factor for the development of certain forms of autoimmune disease. In a prospective study of nearly 80,000 women enrolled in the Nurses’ Health Study, regular consumption of sugar-sweetened soda was associated with an increased risk of seropositive rheumatoid arthritis (RA), independent of other dietary and lifestyle factors.²

Good and consistent evidence exists that the Mediterranean diet is effective in reducing the risk of cardiovascular disease and overall mortality, Dr. Nikiphorou explained.^3,4 This diet mostly entails consumption of fruits and vegetables, beans, nuts, whole grains, fish, olive oil, and small amounts of dairy and red wine. Several components of this diet—including oily fish, cocoa and the resveratrol found in red wine—appear to be associated with reduced inflammation. This association may indicate why patients with RA may benefit by adopting a Mediterranean diet.