A five year-long randomised, placebo-controlled study found that in older adults taking vitamin D supplements, alone or with omega-3 fatty acids, the risk of developing autoimmune disease was reduced.
Autoimmune diseases (AD) such as rheumatoid arthritis, polymyalgia rheumatica, autoimmune thyroid disease and psoriasis, are a leading cause of morbidity and mortality as people age. Few effective treatments are available for AD, but some research has hinted that supplements, including vitamin D and omega-3 fatty acids, could have beneficial effects.
In a new study published in the BMJ, investigators from Brigham and Women’s Hospital evaluated whether taking vitamin D and/or omega fatty acid supplements could affect rates of AD. The large-scale vitamin D and Omega-3 Trial (VITAL), a randomised study which followed participants for approximately five years. Taking vitamin D, or vitamin D and omega-3 fatty acids had a significantly lower rate of AD than placebo.
“It is exciting to have these new and positive results for non-toxic vitamins and supplements preventing potentially highly morbid diseases,” said senior author Karen Costenbader, MD, MPH. “This is the first direct evidence we have that daily supplementation may reduce AD incidence, and what looks like a more pronounced effect after two years of supplementation for vitamin D.”
“Now, when my patients, colleagues, or friends ask me which vitamins or supplements I’d recommend they take to reduce risk of autoimmune disease, I have new evidence-based recommendations for women aged 55 years and older and men 50 years and older,” said Dr Costenbader. “I suggest vitamin D 2000 IU a day and marine omega-3 fatty acids (fish oil), 1000 mg a day – the doses used in VITAL.”
VITAL included 25 871 participants, with men aged 50 and older and women aged 55 and older, conducted to investigate whether taking vitamin D3 and/or omega-3 supplements could reduce the risk for developing cancer, heart disease and stroke in people who do not have a prior history of these illnesses. Prior to the launch of VITAL, investigators determined that they would also look at rates of AD among participants, as part of an ancillary study.
Participants answered questionnaires about new diagnoses of diseases, including rheumatoid arthritis, polymyalgia rheumatica, autoimmune thyroid disease, psoriasis and inflammatory bowel disease, with space to write in all other new onset ADs. Medical records were reviewed to confirm reported diagnoses.
“Autoimmune diseases are common in older adults and negatively affect health and life expectancy. Until now, we have had no proven way of preventing them, and now, for the first time, we do,” said first author Jill Hahn, ScD, post-doctoral fellow at the Brigham.
Among patients randomised to vitamin D, 123 participants in the treatment group and 155 in the placebo group were diagnosed with confirmed AD (22 percent reduction). Among those in the fatty acid arm, confirmed AD occurred in 130 participants in the treatment group and 148 in the placebo group. Omega-3 fatty acids alone did not significantly lower incidence of AD, but there was some evidence of a decrease over long periods.
Source: EurekAlert!