Does Diet Play a Role in Arthritis?
Many people assume that diet has a lot to do with the development of certain diseases, including arthritis — after all, “you are what you eat.” This notion is largely myth.
While healthy diets may increase the chances of good health, current understanding of the most common forms of arthritis suggests almost no role of diet in prevention or treatment. While it is true that diet may affect certain joint disorders, the role of diet is strongest only in rare situations.
For example, gout may be worsened by diets high in purines, a form of protein found in sardines, liver and other organ meats, but this effect is rather weak for most patients. Alcohol intake, if a major part of one’s diet, plays a stronger role. One recent study linked the risk of developing gout with alcohol intake (especially beer), and another linked it with meat and seafood intake. However, the large majority of people who drink beer meat or eat meat or seafood never develop gout.
Patients with celiac disease, a rare condition in which there is an autoimmune reaction to gluten in the diet, occasionally have arthritis as part of the illness. Though it may not always be easy, removal of gluten from the diet can reverse this condition as long as the restrictive diet is followed.
For the more common forms of arthritis and joint pain (including degenerative arthritis, rheumatoid arthritis, lupus, tendonitis and bursitis) there is no clear connection to diet. Efforts to remove certain types of food or add others in an effort to treat arthritis have met with inconclusive or disappointing results. Recent research has identified an association between low vitamin D intake and degenerative arthritis, but it is not known whether it is helpful to take extra vitamin D to prevent or treat degenerative joint disease. In the absence of a particular vitamin deficiency, no clear benefit from supplemental vitamins or nutrients has been established. Weight reduction may help to prevent or treat gout or degenerative arthritis, though clear evidence of benefit is lacking.
While diet may not cause most arthritis, the joints and the intestinal tract are closely linked in certain diseases. Inflammation of the joints (arthritis) and the intestinal tract (colitis, proctitis, ileitis) occur together in “inflammatory bowel disease,” (IBD) a group of illnesses that includes Crohn’s disease and ulcerative colitis. The cause of IBD is unknown. While the bowel problems are the major feature for most patients, up to 20 percent develop a type of arthritis that can be a serious cause of suffering and reduced function. When arthritis is present in IBD, it most commonly affects the spine (spondylitis) and/or one to three joints in the extremities, especially the ankles and knees. Diet is not thought to play in any significant role in either the joint or bowel inflammation, although the bowel inflammation may lead to poor absorption of nutrients. Treatment of the colitis is often effective in treating the arthritis in this condition; otherwise treatment is similar to what is offered for other forms of spondylitis.
Why does the myth about diet and arthritis persist? As is true in other fallacies about health and disease, much of it probably relates to wishful thinking about control: One can presumably control diet and treat the condition accordingly, while accepting an unknown, uncontrollable cause of illness and treating it with medications are much less appealing. It also seems intuitive that diet ought to matter a lot in the development of disease; perhaps it does and we just do not have a good grasp of which diets matter in which diseases.
It may be true that you are what you eat, but having arthritis or worrying that you may someday develop arthritis are not reasons to restrict your diet in most cases. Beyond the usual recommendations of maintaining a balanced diet and trying to achieve optimal body weight, the current impact of diet on arthritis is probably small or negligible. Of course, that could change — over time, a better understanding of the links between nutrition and disease may lead to revisiting the myth as truth. Given our current understanding, that day is probably not soon.