A new study published in Autoimmunity Reviews by Professor Yehuda Shoenfeld, the Laura Schwarz-Kipp Chair for Research of Autoimmune Diseases at Tel Aviv University's Sackler Faculty of Medicine and Tel Hashomer, Head of Zabludowicz Center for Autoimmune Diseases at Chaim Sheba Medical Center, suggests that obesity is a primary factor behind autoimmune disorders such as Crohn’s disease and multiple sclerosis. Autoimmune diseases, in which the immune system attacks bodily tissues and systems rather than pathogenic invaders, affect 5-20% of the global community. According to this new research, obesity leads to a breakdown of the body's protective self-tolerance; creating an optimal environment for immunological chaos. Furthermore, chronic obesity generates a progressively pro-inflammatory environment that is likely to increase the disease's progression and hinder treatment applications. "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 Shoenfeld. "According to the World Health Organization, approximately 35% 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."
Shoenfeld conducted the study on mice diagnosed with multiple sclerosis, which were given a Mediterranean diet rich in unsaturated fats (promoting obesity). Interestingly, he found that Vitamin D deficiency was also a result of obesity, and once corrected, alleviated paralysis and kidney deterioration associated with the disorder. It also improved the prognosis and survival of the mice. "Modern life makes us all prone to Vitamin D deficiency," said Prof. Shoenfeld. "We live in labs, offices, and cars. When Vitamin D is secreted in fat tissue, it is not released into the body, which needs Vitamin D to function properly. Since Vitamin D supplements are very cheap and have no side effects, they are an ideal compound that should be prescribed to anyone at risk of a compromised immune system."
The team explained that the actions of adipokines (compounds secreted by fat tissue and involved in numerous physiological functions, including immune responses) also have a large part to play in the connection between obesity and immunological disease. Shoenfeld and his team conducted a separate systematic review of 329 studies on the relationship between obesity, adipokines, and immune-related conditions (in addition to their current study). "According to our study and the clinical and experimental data reviewed, the involvement of adipokines in the pathogenesis of these autoimmune diseases is clear," said Prof. Shoenfeld. When adipokines are dysfunctional (as promoted with obesity) they aid in the development of a pro-inflammatory environment as well as progressive metabolic inefficiency.