In the past twenty years, Western countries have seen a drastic increase in autoimmune diseases. Since genes can’t change that quickly, we have to attribute it to environmental factors. One of these environmental factors could be obesity. Recent research shows that obesity can trigger and prolong a wide spectrum of autoimmune diseases including MS, rheumatoid arthritis, Crohn’s disease, and lupus.
Autoimmune diseases occur when a person’s immune system perceives the body’s own tissues as foreign invaders and attacks these tissues. The different tissues and locations of the attacks differ from one autoimmune disease to another.
Obesity appears to exacerbate these attacks. Dr. Yong Tsai, certified in clinical immunology, explains that obesity is a result of excess fat, which can generate pro-inflammatory fatty acid and instigate silent inflammation. This silent inflammation is believed to be a leading factor in the development of many autoimmune diseases.
Obesity increases risk of autoimmune disease
A study published in the journal Autoimmunity Reviews reviewed 329 articles that presented data on the relationship between obesity and autoimmune diseases. From these articles, the researchers found that obesity was a factor in the development of MS, lupus, Crohn’s, and type 1 diabetes, and was especially linked to rheumatoid arthritis and psoriatic arthritis. Obesity also worsened the course of lupus, Crohn’s, and rheumatoid and psoriatic arthritis. Additionally, it impaired the treatment response for people with rheumatoid and psoriatic arthritis and Crohn’s disease.
“We’ve been aware of a long list of causes of autoimmune disorders — infections, smoking, pesticides, lack of vitamins, and so forth. But in the last five years, a new factor has emerged that cannot be ignored: obesity,” said Professor Yehuda Shoenfeld, the lead author of the study and Head of the Zabludowicz Center for Autoimmune Diseases at Chaim Sheba Medical Center in Israel. “According to the World Health Organization, approximately 35 percent of the global community is overweight or obese, and more than ten autoimmune diseases are known to be associated with increased weight. So it’s critical to investigate obesity’s involvement in the pathology of such diseases.”
The villains that link obesity and autoimmune diseases could be adipokines, the compounds secreted by fat tissues that contribute to physiological functions such as immune response. These adipokines can become detrimental to the immune system. The researchers concluded that the connection between adipokines and autoimmune diseases is clear, and they may have a direct influence on the development of various conditions.
Vitamin D deficiency
In addition to evaluating the articles, Shoenfeld and his team performed their own research on mice suffering from multiple sclerosis and gave them a Mediterranean diet full of unsaturated fat. They found that obesity results in a vitamin D deficiency, which once corrected, eased paralysis and kidney deterioration, complications associated with MS. Correcting this vitamin D deficiency also led to improved prognosis and survival for the mice.
“When vitamin D is secreted in fat tissue, it is not released into the body, which needs vitamin D to function properly,” Professor Shoenfeld explained.
Vitamin D supplements are cheap and have virtually no side effects, and Shoenfeld recommends people take them for prevention of autoimmune diseases and alleviation of symptoms for those who already have autoimmune diseases.
Obesity creates the optimal environment for autoimmune diseases, from the abundance of adipokines to the decrease of vitamin D. Maintaining a healthy weight can help people at risk for an autoimmune disease, and can relieve symptoms and decrease severity of the prognosis.
Dr. Tsai recommends eating non-starchy vegetables, omega-3 fatty acids found in foods like salmon or olive oil, and lean meat for decreased autoimmune disease symptoms. And make sure to avoid those processed foods, refined grain products, and trans fats.