A recent report in JAMA Ophthalmology from the Moran Eye Center at the University of Utah offers new insight on how over-supplementation affects eye health. Over the past decade, ophthalmologists have prescribed nutritional supplements such as lutein and zeaxanthin to delay vision loss in patients with age-related macular degeneration. Researchers wanted to know if taking more than the recommended dose promotes better vision.
The JAMA study describes a patient without AMD or vision problems who was referred to the retinal clinic for crystal deposits in the macular region of the retina in both eyes. For the past eight years, the patient took daily lutein supplements and ate a lutein-rich diet, which was the equivalent of twice the dose of lutein for an AMD patient.
Lutein and zeaxanthin are antioxidants called carotenoids, which are made by plants and are believed to neutralize light-related eye damage. The body cannot synthesize carotenoids, so they can only be obtained by eating plants or taking supplements.
“When we looked at the patient’s carotenoid levels in serum, skin, and the retina, all measurements were at least two times greater than carotenoid levels in patients not taking nutritional supplements,” said Paul Bernstein, M.D., Ph.D., principal investigator. “The patient quit taking the lutein supplement, but maintained her diet rich in lutein, and, after seven months, the crystals in the right eye disappeared.”
Bernstein and his team stated that they need to conduct a larger clinical trial before making conclusions, but the present research seems to indicate that consuming higher than recommended levels of lutein could have negative effects in patients with AMD. Bernstein advises his patients to eat an “eye-health” diet rich in colorful fruits and vegetables, and that patients should take lutein and zeaxanthin supplements only if their ophthalmologist detects signs of AMD (Source: Science Newsline).