Vitamin D, Omega-3s Don't Lower Risk for Age-Related Macular Degeneration

By Amy Orciari Herman

Edited by André Sofair, MD, MPH, and William E. Chavey, MD, MS

Supplementation with vitamin D or omega-3 fatty acids does not lower the risk for age-related macular degeneration (AMD) or its progression, according to a JAMA Ophthalmology study.

Over 25,000 U.S. adults aged 50 and older were randomized to receive vitamin D supplementation (2000 IU/day) plus marine omega-3 fatty acids (1 g/day), vitamin D plus placebo, omega-3s plus placebo, or double placebo.

During a median 5 years of treatment, 1.3% of participants experienced either incident AMD or worsening of preexisting AMD. Outcomes did not differ significantly regardless of whether participants received vitamin D, omega-3s, or placebo.

The researchers note that prior observational studies suggested a potential benefit for vitamin D in AMD, but such studies could have been limited by residual confounding. Of the current findings, a commentator writes, "These negative results of a large, well-designed, and well-conducted clinical trial, performed by highly experienced investigators, [are] discouraging."