Your Health Checkup: Should You Be Taking Vitamin D and Fish Oil?

Recent studies shed more light on the usefulness of these supplements.

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“Your Health Checkup” is our online column by Dr. Douglas Zipes, an internationally acclaimed cardiologist, professor, author, inventor, and authority on pacing and electrophysiology. Dr. Zipes is also a contributor to The Saturday Evening Post print magazine. Subscribe to receive thoughtful articles, new fiction, health and wellness advice, and gems from our archive. 

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I have often said facetiously that the urine of many Americans has the highest concentrations of vitamins found anywhere in the world since we ingest so many multivitamin/multimineral supplements. Most are not recommended for generally healthy adults, and the excess is just excreted in the urine.

But, like so many issues in science and medicine, recommendations change as new information becomes available. One must be a professional skeptic to doubt, to challenge, and to ask, “Are recommendations still the same?” Case in point concerns vitamin D and fish oil.

Researchers studied the effects of vitamin D (2000 IU/day) and omega-3 fish oil (1000 mg/day) supplements on rates of autoimmune diseases like rheumatoid arthritis, psoriasis, and thyroid problems in almost 26,000 U.S. adults with an average age of 67 years. Both vitamin D and omega-3 supplements are well tolerated and have known anti-inflammatory actions.

Over the 5.3 years of the study, people randomized to receive vitamin D experienced a significant 22 percent decrease in these autoimmune ailments, compared to the placebo group, while the omega-3 fish oil group had 15 percent decrease that was not statistically significant. When only the last three years of the trial were considered, both vitamin D and omega-3 treatment groups showed significant reductions by about 30 percent. Perhaps the fish oil took a longer time to exert an effect.

In another study of over 8,000 patients who had elevated triglyceride levels despite taking statins, fish oil in a concentrated form called icosapent ethyl (brand name Vascepa) significantly lowered the risk of heart attacks, strokes, angina, and cardiovascular death, compared to a placebo. (SEP 5/19/20)

Multiple publications support the benefits of vitamin D supplementation. In one recent study, vitamin D appeared to reduce the incidence of atrial fibrillation and duration of in-hospital stays after coronary bypass surgery.

Even more relevant today is the possibility that vitamin D supplements can help reduce the risk of contracting COVID. Although definitive scientific data are incomplete, over a dozen observational studies offer evidence that serum 25-hydroxyvitamin D concentrations are inversely correlated to the incidence or severity of COVID-19. Vitamin D supplements may reduce virus concentration, the risk of inflammation, and improve blood vessel integrity. Thus, considering its safety, the evidence seems strong enough to recommend vitamin D supplements (1000-2000 IU/day) to help prevent or treat COVID-19, despite the lack of large-scale randomized controlled trials. (Check with your health care provider for further information.)

The take home message is that knowledge of medicine and science evolves, and so do recommendations. We need to stay current to stay healthy.


Featured image: Shutterstock

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