Taking vitamin D daily or a combination of vitamin D with omega-3 fatty acids (which are abundant in seafood) may lower the risk of autoimmune disease, according to a study published in the BMJ journal.
The effect is stronger after two years of using these substances.
According to the researchers, these results are important because supplementation with vitamin D and omega-3 acids is safe, and there are currently no other known methods of reducing the risk of autoimmune diseases.
Autoimmune diseases – what is it?
Autoimmune diseases (otherwise autoimmune, autoimmune) develop as a result of the immune system ‘s erroneous attack on the body’s own healthy tissues. These include diseases such as rheumatoid arthritis , psoriasis , inflammatory bowel disease , rheumatic polymyalgia, or autoimmune diseases of the thyroid gland ( Hashimoto’s disease ).
Both vitamin D and omega-3 fatty acids, which are abundant in seafood, have beneficial effects on the immune system and reduce the inflammation associated with autoimmune diseases.
Vitamin D for immunity
Researchers from Harvard Medical School and Brigham and Women’s Hospital in Boston, Massachusetts, tested whether taking vitamin D and omega-3 fatty acids had an impact on the risk of autoimmune diseases. To this end, they surveyed 25,871 American adults with an average age of 67. Demographic information was collected including age, ethnicity, place of residence, earnings, education, lifestyle, weight, medical history, diet and supplement use. The participants’ blood levels of vitamin D and omega-3 fatty acids were also measured.
They were then randomly assigned to take vitamin D (2,000 international units per day) or placebo, omega-3 fatty acids (1,000 mg per day), or placebo. On average, it was monitored for over five years whether subjects developed an autoimmune disease.
It turned out that in the group using vitamin D , autoimmune disease was confirmed in 123 people, while in the control group – in 155 people. As the researchers calculated, the risk of developing this disease was, therefore, lower by 22 percent. in people taking vitamin D supplementation.
In the group taking omega-3 acids , there were 130 cases of autoimmune disease, while in the control group – 148 cases, which resulted in a 15% reduction in risk, but this result was not statistically significant. Only when the analysis also included probable cases of autoimmune disease, was the decrease in risk statistically significant and amounted to 18%. compared to the placebo group.
The benefits of supplementation were also visible when the analysis included the last three years of the study. At that time, in the group taking vitamin D it was 39 percent. fewer confirmed cases of autoimmune disease, and in the group using omega-3 fatty acids – by 10 percent. less. Together , vitamin D and omega-3 acids lowered the risk of autoimmune disease by 30%.
The researchers emphasize that the study was conducted in a large, diverse population, but only one dose and form of each supplement was used. Furthermore, the results may not be relevant to a younger population of people.
The researchers also note that this is the first direct evidence that daily supplementation of vitamin D or omega-3 fatty acids for five years , or a combination of these substances, can reduce the incidence of autoimmune disease in older adults. The greatest effect is achieved after two years of taking these supplements.
The authors of the study plan to track the health of the study participants for the next two years. In their opinion, similar studies are needed in the younger population and among people particularly at risk of autoimmune diseases.