Dr. Nancy Agmon-Levin and colleagues of the Chaim Sheba Medical Center in Israel recently reviewed the evidence that vitamin D is involved in autoimmune disorders.
Autoimmune disorders occur when the body’s immune system is tricked into thinking that self is foreign and self needs to be destroyed. Thus the immune system makes antibodies that attack various tissues in the body.
Vitamin D administration helps autoimmune disorders by making qualitative and quantitative changes in the immune system (less Th1 and more Th2). This makes the body more tolerant of self and less likely to mount autoimmune responses. Vitamin D also increase the number of T regulatory cells.
In this review, the authors break down many of the autoimmune diseases vitamin D has been implicated in, and what observational studies show:
- Systemic lupus erythematosus can affect any organ. Such patients have lower vitamin D levels and low vitamin D levels correlate with disease severity.
- Antiphospolipid syndrome is a disorder in which antibodies attack lipid cell membranes and such patients have lower vitamin D levels and low levels correlate with disease severity.
- Rheumatoid arthritis is the most common autoimmune disorder in which antibodies attack cartilage. Such patients have lower vitamin D levels and low levels are correlated with disease severity.
- Systemic sclerosis is not well understood, although such patients have low vitamin D levels and the lower the level the worse the disease.
- Multiple sclerosis is a common autoimmune disorder of middle age adults in which antibodies attack the sheaths of nerves. Such patients have low vitamin D levels, and the lower the level, the worse the disease.
- Autoimmune thyroid disease, like that which causes most thyroid disease, is a condition in which antibodies attack the thyroid and such patients have low vitamin D levels and low levels correlate with disease severity.
- Celiac disease is an autoimmune reaction to dietary gluten and disease severity is associated with lower levels of vitamin D.
- Insulin dependent diabetes, also known as type 1 diabetes, is correlated with low vitamin D levels. Increased disease severity is associated with lowest vitamin D levels.
- Crohn’s disease in an inflammatory disorder of the bowel, and severity is linked to the lowest vitamin D levels.
- Primary biliary cirrhosis is an autoimmune disorder with a female to male ratio of 9:1 in which antibodies attack the small bile ducts in the liver. Such patients have low levels of vitamin D and disease severity is correlated with the lowest levels.
- Alopecia areata is an autoimmune disease leading to patchy baldness, and such patients have low levels of vitamin D.
Had enough? The authors wisely conclude,
“Evidence regarding the purported benefit of vitamin D supplementation on a multitude of health benefits has been reported worldwide. Furthermore, given the fact that supplementation of vitamin D in its native form is harmless and inexpensive, we believe that time has come to advocate for wider use of vitamin D supplementation.”