Unlocking Eye Health: The Significance of AREDS 2 Recommended Dosage

In the realm of eye health, the Age-Related Eye Disease Study 2 (AREDS 2) stands as a pivotal landmark, offering invaluable insights into the management of age-related macular degeneration (AMD) and related ocular conditions. Central to the efficacy of AREDS 2 interventions are the recommended dosages, comprised of a carefully calibrated regimen of vitamins and minerals designed to optimize therapeutic outcomes while minimizing potential risks.

AREDS 2 RECOMMENDED DOSAGE graphic

The AREDS 2 study, conducted by the National Eye Institute, examined the impact of nutritional supplements on the progression of AMD, a leading cause of vision loss in older adults. Building upon the findings of its predecessor, AREDS, the study evaluated the efficacy of specific formulations containing antioxidants and minerals in reducing the risk of advanced AMD and associated vision loss.

Key constituents of the AREDS 2 formulation include:

  1. Vitamin C: With its potent antioxidant properties, vitamin C plays a crucial role in combating oxidative stress, a hallmark of AMD pathology. The recommended dosage of 500 milligrams of vitamin C per day reflects the optimal balance between therapeutic efficacy and safety considerations (1).

  2. Vitamin E: Another potent antioxidant, vitamin E, was included in the AREDS 2 formulation at a dosage of 400 International Units (IU) per day. Vitamin E works synergistically with vitamin C to neutralize free radicals and protect retinal cells from oxidative damage (2). Importantly, Vitamin E is supplied in eye supplements in either synthetic (DL-alpha) or natural (D-alpha) forms. Only the D-alpha natural form is made from plant oils. This is the preferred and more costly form of Vitamin E used exclusively in VisiVite eye vitamins.

  3. Zinc: Essential for retinal pigment epithelial function and cellular repair mechanisms, zinc is a cornerstone of the AREDS 2 regimen. The recommended dosage of 25-80 milligrams of zinc per day, in combination with copper supplementation, helps maintain retinal integrity and supports overall ocular health (1). Notably, the AREDS 2 study found no signficant difference comparing the effectiveness of the low and high ends of the dosage range. 

  4. Copper: While zinc is critical for ocular function, it can interfere with copper absorption when taken in high doses over an extended period. To counteract this potential imbalance, AREDS 2 includes a modest dosage of 1-2 milligrams of copper per day, depending on the daily zinc dosage, ensuring optimal copper-zinc equilibrium (4).

  5. Lutein and Zeaxanthin: These carotenoids, found abundantly in green leafy vegetables, are integral components of the macular pigment, which acts as a natural filter against harmful blue light and oxidative stress. The recommended minimum dosages of 10 milligrams of lutein and 2 milligrams of zeaxanthin per day help bolster macular health and preserve visual function (3). Because the safety of lutein and zeaxanthin is so generous, higher doses of these two ingredients are often found in premium AREDS 2 supplements. Lutein is typically sourced from marigold flowers. Zeaxanthin can be sourced from plants as well, including paprika, and like Vitamin E, is available in natural and mixed synthetic forms. Many eye vitamin manufacturers use the zeaxanthin that spills off during lutein extraction. But VisiVite uses only the pure, natural, Right-Right molecular form of zeaxanthin and indicates the individual sourcing of this highly critical ingredient on each of its products.

The meticulous selection of these nutrients and their respective dosages underscores the commitment of AREDS 2 investigators to evidence-based ocular therapeutics. By elucidating the optimal balance between efficacy and safety, the recommended dosage serves as a guiding principle in the management of AMD and related conditions.

However, it is essential to recognize that individual variations in genetics, diet, and medical history can influence outcomes. One example is that people who take anticoagulants may not wish to increase their risk of bleeding and take an AREDS 2 formula without Vitamin E.

 

References:

  1. Age-Related Eye Disease Study 2 Research Group. "Lutein + zeaxanthin and omega-3 fatty acids for age-related macular degeneration: the Age-Related Eye Disease Study 2 (AREDS2) randomized clinical trial." JAMA 309.19 (2013): 2005-2015.

  2. Chew, Emily Y., et al. "Long-term effects of vitamins C and E, β-carotene, and zinc on age-related macular degeneration: AREDS report no. 35." Ophthalmology 120.8 (2013): 1604-1611.

  3. Chew, Emily Y., et al. "Secondary analyses of the effects of lutein/zeaxanthin on age-related macular degeneration progression: AREDS2 report no. 3." JAMA ophthalmology 132.2 (2014): 142-149.

  4. SanGiovanni, John Paul, et al. "The relationship of dietary carotenoid and vitamin A, E, and C intake with age-related macular degeneration in a case-control study: AREDS Report No. 22." Archives of ophthalmology 125.9 (2007): 1225-1232.