Omega-3s and vitamin D reduce eye disease
In Western populations, fluid pressure within the eye (intraocular pressure, or IOP) increases with age, but in Japan, where diets are rich in omega-3s from fish oil, the reverse is true. Elevated IOP increases chances for glaucoma, which can cause blindness, so doctors are looking for non-drug ways to reduce IOP.
In this study, 105 adults with normal IOP and no current or prior diagnosis of glaucoma, took a placebo or 1,000 mg EPA, 500 mg DHA, and 900 mg alpha-linolenic acid per day.
After 90 days, IOP had increased slightly in the placebo group, and had declined by 8 percent in the omega-3 group. Discussing the findings, doctors said, “To our knowledge, this is the first study to report that omega-3 fatty acids lower IOP in humans.”
Noninfectious uveitis (NIU) is a serious sight-threatening inflammatory condition of the eye. In this study doctors compared vitamin D levels in 558 people with NIU to 2,790 people without NIU—meaning five for each person with NIU—on the basis of age, sex, race, ethnicity, and a recent vitamin D measurement. People with vitamin D levels of at least 21 nanograms per milliliter of blood were 21 percent less likely to have NIU compared to those with lower vitamin D levels.
In a similar study, doctors compared vitamin D levels in 436 people with uveitis or scleritis—another inflammatory eye disease—to 329 matching people without eye disease. Those with low vitamin D levels were nearly twice as likely to have uveitis compared to similar people with normal vitamin D levels.