Best-selling eye vitamins don’t match scientific evidence – sciencedaily
With Americans spending billions of dollars each year on nutritional supplements, researchers analyzed popular eye vitamins to determine if their formulations and claims are consistent with scientific findings. They determined that some of the top-selling products do not contain ingredient strengths identical to the eye vitamin formulas that have been proven to work in clinical trials. In addition, the study found that claims made on product promotional material lack scientific evidence. The results of their study were published online in Ophthalmology, the journal of the American Academy of Ophthalmology.
The leading cause of blindness in the elderly in the United States is age-related macular degeneration (AMD). This is the deterioration of the macula of the eye, which is the central part of the retina that allows the eye to see the smallest details clearly. The recommended treatment for AMD at certain stages of the disease includes nutritional supplements. The landmark Age-Related Eye Disease Study (AREDS) found in 2001 that a specific formulation of nutritional supplements containing high doses of antioxidants and zinc could slow the worsening of AMD in people with AMD. intermediate AMD and those with advanced AMD in one eye only. A follow-up study that ended in 2011, AREDS2, determined that the formula was still effective if one ingredient, beta-carotene (a form of vitamin A), was replaced by related nutrients, lutein and zeaxanthin. . Beta-carotene has been substituted in AREDS2 because of its link with an increased risk of lung cancer in smokers. Both studies have resulted in increased sales of eye supplements marketed as containing the AREDS or AREDS2 formulas.
To test whether the products were consistent with the study results, the researchers compared ingredients from top-selling brands to the exact formulas proven effective by AREDS and AREDS2. The researchers – based at Yale-New Haven Hospital-Waterbury Hospital, Penn State College of Medicine, Providence VA Medical Center, and Warren Alpert Medical School of Brown University – identified the top five selling brands based on market research gathered. from June 2011 to June. 2012, and analyzed the 11 brand products.
They found that while all the products studied contained ingredients from the AREDS or AREDS2 formulas:
- Only four of the products contained equivalent doses of AREDS or AREDS2 ingredients
- Four other products contained lower doses of all AREDS or AREDS2 ingredients
- Four of the products also included additional vitamins, minerals and herbal extracts that are not part of the AREDS or AREDS2 formulas.
Additionally, while the 11 promotional materials for the products contained claims that the supplements “support”, “protect”, “help” or “promote” vision and eye health, none contained claims that nutritional supplements do not. have been shown to be effective only for people with specific stages of AMD. Nor have there been any statements clarifying that there is currently insufficient evidence to support the routine use of nutritional supplements for the primary prevention of eye diseases such as AMD and cataracts.
“With so many vitamins claiming to support eye health, it is very easy for patients to be misled into purchasing supplements that may not bring desired results,” said first author Jennifer J. Yong, MD. “Our results underscore the importance of ophthalmologists advising patients that they should only take the proven combination of nutrients and doses for AMD in accordance with guidelines set by AREDS and AREDS2 for the onset of eye disease. such as cataracts and AMD. “
A table of the results of the analyzed products is available at http://www.aao.org/newsroom/release/upload/Table-1-OcularNutritionalSupplements-InPress.pdf (PDF file).
The American Academy of Ophthalmology recommends that ophthalmologists consider supplementation with antioxidant vitamins and minerals, according to the AREDS and AREDS2 trials, for patients with intermediate or advanced AMD. He also maintains that, based on the six-year period of the AREDS trial, there is no evidence to support the use of these supplements for patients with lower to intermediate AMD. Ophthalmologists can read the Academy’s AMD Preferred Practice Pattern guidelines at http://bit.ly/aaoamdppp. The public can learn more about AMD and AREDS supplements at http://bit.ly/eyesmartamd.
Dietary supplements are not evaluated or regulated for efficacy or safety under the Dietary Supplement Health and Education Act (DSHEA) of 1994. In addition, FDA approval does not. is not required for the marketing of dietary supplements.
Notable press studies recently published online in Ophthalmology understand:
- Long-term effects of ranibizumab treatment on the severity of diabetic retinopathy and initial risk factors for worsening retinopathy: This exploratory analysis revealed that when intravitreal ranibizumab is given for up to 3 years, it may both improve the severity of diabetic retinopathy and prevent its worsening. He also found that prolonged delays in initiation may limit the therapeutic effect and that, although rare, the development of proliferative diabetic retinopathy still occurs in some eyes subjected to anti-VEGF treatment. This effect may be related to the presence of macular non-perfusion.
- Genetic testing in people with age-related macular degeneration and the use of AREDS supplements: to test or not to test? : The controversy surrounding the use of genetic testing to guide the treatment of people with AMD continues. This report provides the background to genetic testing for patients with AMD and the reasons why it is not recommended.
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