Health topics: diet and arthritis

Arthritis refers to painful inflammation of the joints. There are many types of arthritis: some acute and transient without long-term consequences, others chronic and causing decades of debilitating pain and immobility. Below is a discussion of three common types of arthritis and how diet may play a role in the disease process.

Osteoarthritis is a type of chronic arthritis characterized by inflammation and degeneration of the joint. We often speak of a “wear and tear” disease of the joint due to lifelong use; However, research has shown that osteoarthritis is not simply a disease of aging. Risk factors that we can control, such as poor biomechanics, muscle weakness and obesity, play an important role in the disease process. Diet also plays a role.

In a study published in 2015 in the journal Arthritis, researchers studied the effect of a whole-food, plant-based diet (WFPB) on osteoarthritis. They conducted a randomized controlled trial, that is, they randomly assigned participants with osteoarthritis to a WFPB diet and compared them to participants who continued their usual omnivorous diet. Within two weeks, participants following the WFPB diet reported a significant reduction in pain and improved functioning compared to the control group.

Another study involving a larger group of people found equally promising results. The 2006 studypublished in the Journal of Nutrition, Health and Aging, found that eating meat just once a week (compared to not eating meat) was associated with an increased risk of osteoarthritis of 31 percent in women and 19 percent in men. Eating meat more than once a week was associated with a 49 percent increased risk in women and 43 percent in men.

In another big study Published in Annals of Rheumatic Diseases, researchers used data from two large cohorts to examine the association between fiber (a nutrient found exclusively in plant foods) and the risk of knee osteoarthritis. Those who consumed the highest amounts of fiber had a 30% lower risk of knee osteoarthritis in one cohort and a 61% lower risk in the other cohort.

Although not fully understood, the effect of a healthy diet on osteoarthritis may be mediated by a reduction inflammation and promoting healthy body weight. Overweight and obese people are finished twice more likely to develop osteoarthritis than normal weight individuals, and even minimal weight loss can significantly reduce this risk. Because plant-based diets are partner with lower body weight and weight reduction, this can make them powerful tools in the treatment or prevention of osteoarthritis.

Rheumatoid arthritis (RA) is an autoimmune disease. The immune system normally recognizes self from non-self as a means of defending the body against foreign invaders (e.g., bacteria, parasites). In autoimmune diseases, the immune system inappropriately attacks certain parts of the body. In RA, the target is the synovium, a tissue that lines the inner surface of joints. This leads to a chronic inflammatory response that distorts the joints and surrounding tissues. Certain factors increase the risk of developing RA, including genetic factors, smoking and obesity.

Although the data is limit on the subject, some studies have shown that diet could play a role in the prevention and treatment of RA. In a 2003 study Published in Annals of Rheumatic Diseases, researchers randomized participants with rheumatoid arthritis to follow a Mediterranean diet (which emphasized fruits, vegetables, whole grains, legumes, and nuts) or to continue their diet normal. After 12 weeks, the Mediterranean diet group showed decreased disease activity, fewer swollen joints and less pain compared to those who didn’t make dietary changes.

In another randomized control trial published in the American Journal of Clinical Nutrition, researchers tested the effect of fasting for 7 to 10 days followed by a vegan diet for 3.5 months in RA patients. After one month of intervention, the vegan diet group had reduced pain, less morning stiffness, and fewer tender and swollen joints compared to the omnivore group.

Although these results are promising, larger studies are needed to validate their findings and further elucidate the effect of plant-based diets on RA.

Gout is an inflammatory disease caused by the deposition of urate crystals in various tissues of the body, including the joints. Uric acid is a breakdown product of compounds called purines, found in high concentrations in meat, seafood, and alcohol. At high levels in the body and under certain circumstances, uric acid can form crystals that trigger a painful inflammatory response. Due to differences in purine content among foods and their role in the disease process, extensive research has been conducted on the effect of diet on gout risk.

A study published this year in Clinical Nutrition included two cohorts totaling 13,935 people followed for more than eight years on average. The authors studied the effect of a vegetarian diet on the incidence of gout and found that those who followed a vegetarian diet were a third more likely to have gout than non-vegetarians, even after taking into account differences in other risk factors (e.g., age). , smoking, alcohol consumption) in their statistical model.

A big study published in 2004 in the New England Journal of Medicine followed 47,150 men over a 12-year period and compared the meat consumption of men who developed gout with those who remained healthy. They found that those who ate the greatest amount of meat and seafood were 41% and 51% more likely to develop gout, respectively, than those who ate the least amount of meat and seafood. Interestingly, they found that vegetables high in purines were not associated with an increased risk of gout.