Taking daily Vitamin D and Omega-3 fish oil supplements may help protect older adults from developing autoimmune disorders such as rheumatoid arthritis, psoriasis, and other inflammatory diseases that cause muscle pain and stiffness in the shoulders and hips, a new study has found.
People age 50 and older taking 2,000 IU (International Units) of Vitamin D3 for over five years had a 22% lower relative rate of confirmed autoimmune diagnoses, said study author Dr. Karen Costenbader, a professor of medicine at Harvard Medical School in the division of Rheumatology, Inflammation and Immunity and the director of the lupus program at Brigham and Women's Hospital in Boston.
That dosage is two to three times the recommended daily dose of Vitamin D for adults, which is 600 IU for people up to 69 years old and 800 IU for those age 70 and up, according to the National Institutes of Health.
Once people had been taking Vitamin D for at least two years, the prevention rate from autoimmune disorders rose to 39%, according to the study by the British Medical Journal. This study also found a possible link between taking 1,000 milligrams of omega-3 fatty acid (fish oil) and a reduction in autoimmune disorders. This study did find that taking both Vitamin D and omega-3 fatty acid supplements, versus the placebo alone, decreased autoimmune disease by about 30%.
But people should not just run out and start popping Vitamin D supplements to boost their chances of avoiding autoimmune disease, Costenbader warned, as there are significant consequences to taking too much of the supplement. Unlike water-soluble vitamins, which the body can easily eliminate, Vitamin D is stored in the fat cells of the body and can build up to toxic levels, leading to bone pain and kidney damage.
Because the body makes Vitamin D when the skin is exposed to sunshine, and milk and other foods are often fortified with Vitamin D, many experts say healthy, younger people are not likely to require Vitamin D supplements, especially in amounts over the recommended level of 600 IU per day. Levels do drop in older age, but "I would say everybody should speak to their doctor first before taking 2000 IU of Vitamin D on top of whatever else you're taking," Costenbader said. "And there are certain health problems such as kidney stones and hyperparathyroidism (a rise in calcium levels), where you should not be taking extra Vitamin D."
At five years into the research, the study could not tease apart which of the 80 or more autoimmune diseases might benefit most from Vitamin D and fish oil supplements, Costenbader said, but research is continuing. The study is now in its seventh year, she said, and more data should be released in the future.