Eye health—don’t wait for your eyes to give you trouble before you start concerning yourself with giving them the nutrients they need to thrive. Because the only protection eyes have from UV rays are sunglasses, antioxidants that help fight free radicals are important to eye health. Good blood flow in the body also plays a key role in how healthy your eyes remain. Read on for recent findings about the benefits of essential fatty acids and antioxidants for eye health.
Omega-3s and Pressure in the Eye
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.”
Reference: Translational Vision & Science Technology; May, 2018, Vol. 7, No. 3
DHA decreased macular thickness
The macula is an area in the center of the retina of the eye responsible for sharp, straight-ahead vision. Chronic high blood sugar levels in diabetes can damage blood vessels near the retina, allowing fluid to build up in the macula (macular edema), distorting vision.
In this study, 55 people with diabetic macular edema took 0.5 mg of ranibizumab, a medication that stops fluid leakage in the eye, once per month for the first four months, then as needed. About half the group took 1,050 mg of the omega-3 DHA per day during this time.
After three years, those taking DHA had an average 11 percent greater decrease in macular thickness, to 275 micrometers compared to 310. The DHA group also had greater improvements in visual acuity, lower long-term average blood sugar levels, higher total antioxidant capacity, and fewer signs of chronic inflammation.
Reference: Retina; February, 2018, Published Online
Veggies for Vision
Green leafy vegetables and beetroot contain nitrate, a precursor of nitric oxide, the molecule that helps blood vessels relax, increasing blood flow. In this study, doctors measured the diets of 2,037 adults, aged at least 49, and followed up 15 years later.
Those who consumed between 100 and 142 mg of vegetable nitrates per day were 35 percent less likely to have developed early-stage age-related macular degeneration (AMD) compared to those who got less than 69 mg per day. AMD blurs or eliminates sight in the center of the field of vision; one of the most common age-related eye conditions.
Reference: Journal of the Academy of Nutrition and Dietetics; 2018, Vol. 188, No. 12, 2311-4
Vitamin K for Vision
Good vision depends on good circulation in the eye, and matrix Gla protein (MGP) helps prevent calcium buildup in blood vessels and arteries (vascular buildup), promoting good circulation. But MGP needs adequate levels of vitamin K to become activated. In this study, doctors measured vitamin K levels in 935 men and women, and followed up 11 years later.
Those with the highest levels of vitamin K also had the greatest levels of activated MGP. Doctors also saw that those with the highest levels of inactive MGP were most likely to have smaller vascular diameter in the retina of the eye, reducing circulation.
Reference: Scientific Reports; October, 2018, Vol. 8, Article No. 15088
A cataract clouds the lens of the eye, reducing vision, and usually develops with age. Doctors believe antioxidants and the colorful carotenoids help protect the eye. In this analysis, doctors reviewed eight placebo-controlled trials, plus 12 studies following men and women over several years. Overall, for every 10 mg increase per day of lutein or zeaxanthin, chances for age-related cataract declined 26 percent. Each 500 mg daily increase in vitamin C lowered chances 18 percent; each 5 mg increase in beta-carotene, 8 percent; and each 5 mg daily increase in vitamin A lowered chances of cataract by 6 percent.
Reference: American Journal of Clinical Nutrition; 2019, Vol. 109, No. 1, 43-54
Vitamin A preserved children’s sight
Special cells in the retina of the eye, called cones, respond to colors in bright light. These cones can begin to fail—part of a group of eye diseases called retinitis pigmentosa (RP)—in adolescents and young adults, often leading to blindness by age 40. In this study, 80 children, average age nine, with different genetic types of RP, took age-adjusted doses of vitamin A less than or equal to 15,000 IU per day, or did not take vitamin A.
Doctors followed up four to five years later and found children taking vitamin A had nearly 50 percent slower annual loss of cone function compared to those not taking vitamin A: 6.9 percent vs. 13.2 percent. Doctors said treating RP in childhood appears to have greater benefit than in adulthood, where other studies have found only a 17 percent slower annual loss of cone function for those taking vitamin A.
Reference: JAMA Ophthalmology; March, 2018, Published Online
It’s never too early to claim the benefits of good nutrition choices for eye health. Start now and avoid the regrets of waiting until your eyes give you problems before you pay attention to their nutrient needs.
Articles copyright Natural Insights for Well Being 2019. All rights reserved. Used with permission.