By Joseph E. Scherger, MD, MPH
Core Faculty, Eisenhower Health Family Medicine Residency Program, Eisenhower Health Center, La Quinta, CA; Clinical Professor, Keck School of Medicine, University of Southern California, Los Angeles
Continued use of vitamin D3 and n-3 fatty acids reduced the incidence of autoimmune diseases such as psoriasis.
Costenbader KH, Cook NR, Lee IM, et al. Vitamin D and marine n-3 fatty acids for autoimmune disease prevention: Outcomes at two years after VITAL trial completion. Arthritis Rheumatol 2024; Jan 25. doi: 10.1002/art.42811. [Online ahead of print].
A study group from Harvard has been looking at the effect of vitamin D and fish oil supplementation on a variety of autoimmune diseases. The VITAL trial was published in the British Medical Journal in 2022.1 The randomized controlled trial showed a reduction in autoimmune diseases from both supplements taken together or separately. The daily dose of vitamin D3 was 2,000 IU and the daily dose for marine fish oil was 1,000 mg. I reported on this trial previously in Internal Medicine Alert.2 This study was a continuation for two years of 12,786 men aged 50 years and older and 13,085 women aged 55 years and older who were followed to evaluate whether the benefits were sustained. Over two years after trial termination, the protective effects of vitamin D dissipated but the benefits of fish oil were sustained. The strongest effect was a reduction in skin psoriasis.
COMMENTARY
There are many reasons to take vitamin D and fish oil supplements. This study looked at just one: reduction in autoimmune diseases. I have an online connection with my patients and when I shared this study, one patient indicated that after he started supplementing with vitamin D3 and fish oil, his psoriasis disappeared. It always is nice to receive validation of a study from patient experience.
In choosing supplements for patients, we should make sure there is real benefit beyond a healthy diet and minimize any risk. Vitamin D has many known health benefits and is deficient in much of the population because of modern diets and less direct sun exposure.3 Fish oil supplements are more controversial, but I am convinced of the health benefits and take one myself daily. Fish oil does not carry significant risk and was seen as the most beneficial in this study.4
Recommending supplements is at the discretion of the physician and taking them is at the discretion of the patient.
REFERENCES
- Hahn J, Cook NR, Alexander EK, et al. Vitamin D and marine omega 3 fatty acid supplementation and incident autoimmune disease: VITAL randomized controlled trial. BMJ 2022;376:e066452.
- Scherger JE. Reduce the risk of autoimmune disease with vitamin D, n-3 fatty acid supplements. Internal Medicine Alert 2021;43:188.
- National Institutes of Health. Office of Dietary Supplements. Vitamin D: Fact Sheet for Health Professionals. Updated Sept. 18, 2023. https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
- LeWine HE. Fish oil: Friend or foe? Harvard Health Publishing. Published April 15, 2020. https://www.health.harvard.edu/blog/fish-oil-friend-or-foe-201307126467