7 crucial questions about AREDS2

The results of the second Age-Related Eye Disease Study (AREDS2) are out. In the coming months and years, this study will affect how optometrists approach patient nutrition and eye care.

These nutrients are powerful antioxidants that work like internal sunglasses.

 Here are some frequently asked questions about AREDS2, its results and its implications for the future.

 Q: Where can I find the results of AREDS2?
A: The initial results have been published in the Journal of the American Medical Association (JAMA) and JAMA Ophthalmology.

Q: Is the National Eye Institute recommending lutein and zeaxanthin because of the potential safety issues with beta carotene?
A: No. AREDS2 confirmed results from nearly two decades of observational research about luetein and zeaxanthin. This past research has demonstrated the association between consuming lutein and zeaxanthin in food and a reduced risk of age-related macular degeneration (AMD). Many independent peer-reviewed studies also have shown that supplementation with lutein and zeaxanthin has a positive impact on eye health and function.

Q: Why might lutein and zeaxanthin be helpful?

A: Lutein and zeaxanthin are deposited in the macula to create a protective layer known as macular pigment. These nutrients are powerful antioxidants that work like internal sunglasses, filtering out harmful blue light and protecting the eye from retinal tissue damage and oxidative stress. Research shows that a thicker, denser macular pigment can block more damaging blue light, reducing the risk of certain eye conditions such as AMD.

Q: What did the findings say about cataracts?
A: The results published in JAMA Ophthalmology evaluated the effect of lutein and zeaxanthin on progression to cataract surgery, development of any cataract and development of any severe cataract. Subjects in the lowest quintile of dietary lutein and zeaxanthin intake saw a 32 percent reduction in progression to cataract surgery, a 30 percent reduction in development of any cataract and a 36 percent reduction in development of any severe cataract.

Q: Is it true that lutein supplementation of more than 10 mg per day may be toxic?
A: More than 10 published peer-reviewed studies have included supplementation of more than 10 mg of lutein per day. None of these studies have demonstrated any toxicity. In addition, the Joint FAO/WHO Expert Committee on Food Additives evaluated the safety of lutein and zeaxanthin in 2004. They determined the acceptable daily intake for lutein plus zeaxanthin was 0 to 2 mg/kg body weight.

Q: How do the subjects in AREDS2 differ from the subjects in AREDS1?
A: AREDS1 included people who had all stages of AMD. AREDS2 subjects were at a more advanced stage of the disease and were on average five years older (average age 74) than those in AREDS1 (average age 69). The authors note that these differences could affect the ability to detect a more significant reduction in the disease progression. In addition, some AREDS1 participants took Centrum, which did not contain lutein at the time. Some AREDS2 participants took Centrum Silver, which does contain lutein.

Q: How do people get lutein and zeaxanthin?
A: Lutein and zeaxanthin are found naturally in foods such as spinach, kale, red peppers, eggs and corn. The lutein used in AREDS2 was FloraGLO brand lutein, which is a free, purified lutein from marigolds. The zeaxanthin used in AREDS2 was Optisharp Zeaxanthin, which is the dietary form of zeaxanthin. A third component of the macular pigment, meso-zeaxanthin, is not found in the diet. The body has to make it from lutein, so it exists only as a supplement.

Courtesy of Kemin Health

June 24, 2013

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