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A new study looks into the preventive potential of vitamin D and omega-3 supplements for autoimmune diseases. MirageC/Getty Images
  • Autoimmune diseases like rheumatoid arthritis, psoriasis, lupus, and inflammatory bowel disease affect more than 24 million Americans.
  • Supplements that help regulate inflammation and chronic pain — and that can forestall the effects of autoimmune diseases — have shown to be effective.
  • Researchers have been looking into two supplements in particular — vitamin D and omega-3 fatty acids.
  • A recent study of more than 20,000 participants showed that two years after a randomized five-year trial period, the benefits of vitamin D in preventing autoimmune diseases had waned while those of omega-3 were still strong.

A recent study of more than 20,000 participants showed that two years after a randomized five-year trial period, the benefits of vitamin D in preventing autoimmune diseases had waned while those of omega-3 fatty acids were still strong.

In the study, published in January in the journal Arthritis & Rheumatology, the authors said that 21,592 participants in the VITAL trials — conducted among more than 25,000 total participants to determine the effects of vitamin D and omega-3 supplements on cancer and cardiovascular disease — were followed for an additional two years after the supplements were discontinued.

Among that population of the participants, who were men over 50 and women over 55, the study authors found 236 new cases of confirmed autoimmune disease since the initial trial’s results were published, 65 probable cases in the 5.3 years of the randomized trial, and 42 probable cases diagnosed during the 2-year observational phase.

After the two-year observation period, 255 people who had randomly received vitamin D had a newly developed confirmed autoimmune disease, compared with 259 who had received a vitamin D placebo, a nonsignificant hazard risk (HR) of 0.98.

There were 234 confirmed autoimmune disease cases among people who received omega-3 supplements, compared with 280 among those who received a placebo — a statistically significant HR of 0.83.

“Two years after trial termination, vitamin D 2000 IU/day’s protective effects dissipated, but 1000 mg/day n-3 fatty acids had a sustained effect in reducing AD incidence,” the authors wrote.

Autoimmune diseases, which affect more than 24 million people in the United States, are diseases characterized by the immune system attacking otherwise healthy tissue. They include conditions like psoriasis, psoriatic arthritis, rheumatoid arthritis, lupus, Hashimoto’s thyroiditis, Grave’s disease, inflammatory bowel disease (IBD), celiac disease, and type 1 diabetes.

Treatments for these conditions can be costly and long-term, and the effects of vitamin D and omega-3 supplements have long been known as beneficial to stall autoimmune diseases.

According to the study in question, vitamin D is capable of regulating genes involved in inflammation, and the body cannot make the essential n-3 fatty acids eicosapentaenoic acid (EPA) and docosahexanoic acid (DHA), which are found in fish oil supplements.

Randomized controlled trials conducted in the 1980s and 1990s have shown the effectiveness of fish oil supplements against inflammation and pain associated with autoimmune diseases.

Melanie Murphy Richter, a registered dietitian nutritionist and the director of communications for Prolon, who was not involved in the study, told Medical News Today that the overall lack of vitamin D in most people means supplementation is critical.

“Most people (even those who live in sunny locations like Los Angeles or Florida) are deficient in vitamin D. In fact, 1 billion people worldwide have a vitamin D deficiency, with 50% of the population having a vitamin D insufficiency (low-normal levels). In the U.S. alone, more than 35% of adults are deficient,” Richter said.

“Vitamin D is revered in the medical community for its antioxidant-like qualities and its ability to regulate a variety of immune functions, like B cell and T cell regulation (the functions responsible for suppressing pro-inflammatory cytokines in the body and increasing anti-inflammatory properties in the body). It has the ability to reduce inflammation and plays a role in maintaining the integrity of the gut lining. Our gut health is critical in managing symptoms for autoimmune patients, too.”
— Melanie Murphy Richter, dietitian nutritionist

Kristin Kirkpatrick, a registered dietitian at the Cleveland Clinic Dept of Department of Wellness & Preventive Medicine in Cleveland, Ohio, and a senior fellow at the Meadows Behavioral Healthcare in Wickenburg, Arizona, who was also not involved in the study, told MNT that while the study supports the use of these supplements, there are a number of other factors to consider when it comes to a holistic look at health.

“Supplementation should be considered only with the addition of high-nutrient-dense diet, good quality sleep, stress management and limitation of sedentary behavior,” Kirkpatrick said, adding that consumers should have some caveats when it comes to looking for vitamin D or omega-3 supplements.

What to look for in supplements

“Two things come to mind that are important for both. 1. Quality – not all supplements are created equal and in an unregulated market, consumers need to do their homework on the best options. 2 – dose. The dose for vitamin D, for example, may be considered alongside current D levels. and for omega 3’s, dose may be dependent on outside consumption from food of omega 3’s.”
— Kristin Kirkpatrick, registered dietitian

Murphy added that the study had a particularly narrow focus and didn’t consider lifestyle modifications that could also affect autoimmune disease.

“The main population was older adults, which means that the results might not be generalizable to a younger population. The study only looked at one dose and formulation of each supplement, which could impact future outcomes,” Murphy said.

“A more comprehensive study should look at a more diverse population base with a younger subsect of participants, as well as varying dosages. It should also consider finding ways to control external impacts like diet, lifestyle, and stress factors,” she added.