The AREDS & AREDS2 studies only included people with Age-Related Macular Degeneration (AMD). The supplements have NOT been studied for people with other types of macular degeneration so we don’t know if they are safe and effective.
The two largest studies conducted on supplemental nutrients were AREDS (results published 2001) and AREDS2 (results published 2013). Thousands of people were studied over a long period of time – an average of 5 years each.
I Don’t Have AMD or I Have Early AMD – Does This Conversation Apply to Me?
Great question! No, it doesn’t. The AREDS results showed that there was no benefit for those with no AMD or early AMD. Because of those results, those groups were not included in AREDS2. AREDS and AREDS2 both found benefit for those with intermediate AMD or wet AMD in one eye but not the other.
So, if you are a candidate for AREDS/AREDS2 supplements, the rest of the page is for you.
Before you take any supplement, you should discuss it with your medical doctor especially if you have other health issues and take other supplements and medications. There can be risks for some people.
Both studies included a treatment group whose participants took 80mg of zinc. Also, in AREDS2 there was a treatment group whose participants took 25mg of zinc. In that study, there was no difference in the results between the 80mg and 25 mg of zinc groups.
In 2008, researchers used the DNA collected from many of the AREDS participants to look at a person’s genetic makeup on two genes (CFH & ARMS2) and their response to the AREDS formulation to see if there was a connection. The authors proposed a connection between the high dose of zinc (80 mg) and a person’s response benefit from taking the AREDS formulation. What followed was a lot of back and forth between research teams, accusations of conflict of interest, lots of money for some, criticism of statistical methods and results and more.
The Bottom Line: Some People Should NOT Take Zinc in Supplement Form
Two studies used the DNA from AREDS and looked at a total of 4 genotype groups made up of combinations of risk alleles on two genes: CFH and ARMS2. The studies are cited below (Awh, et al. 2015 and Vavvas, et al. 2018). Trust me, it’s complicated to try to explain what that the exact definitions are of genotypes and genes. If you want the details, let me know and I’ll point you to them.
The results of these studies showed that for 30% of the people whose DNA they looked at in 2 of the 4 groups, taking zinc caused their AMD to progress FASTER than those who did NOT have that genotype. The rest of them, 70%, either got benefit from taking the AREDS formulation with zinc or it didn’t matter whether they took the formulation with or without zinc.
How Do I Know If I Should or Should NOT Take Zinc?
The only way to know for sure is through genetic testing. Genetic testing is available for those in the US and Canada through your physician. The company that does the testing is ArcticDX. Many insurance companies, including Medicare, pay for the test or there is a minimal cost ($50). See our disclaimer below. Click here to find a physician.
What If I Want the Testing But My Doctor Won’t Order It or I Live Outside the US or Canada?
Contact ArcticDX through their Contact Us page.
What Do I Do If I’ve Not Yet Had Genetic Testing?
If you don’t know for sure, the safest thing is to take an AREDS2 supplement with no zinc. Here’s a chart with some of the options.
I Take a Multivitamin – Should I Worry About the Zinc In It?
75% of the participants in the AREDS study also took the Centrum multivitamin which has somewhere between 8-11 mg of zinc. That’s fine.
Will I Get Too Much Zinc From My Diet?
Only if you eat a lot of oysters! It’s estimated that we get 5-10 mg of zinc in our diet as did the people in the AREDS study. That’s fine.
Give Me One Compelling Reason to Get the Genetic Test
Above I mentioned that there were 4 groups of genotypes that were studied. Two of them (approximately 15% each of the total number of people studied) are people who are zinc sensitive. One of the genotypes (approximately 45% of the total number of people studied) got a significant BENEFIT from taking the AREDS supplement with zinc. The fourth group had the same benefit whether they took AREDS with or without zinc. That means 70% of the total population in these studied CAN take AREDS2 with zinc.
References
2015 Awh, et al., Treatment response to antioxidants and zinc based on CFH and ARMS2 genetic risk allele number in the Age-Related Eye Disease Study.
2018 Vavvas, et al., CFH and ARMS2 genetic risk determines progression to neovascular age-related macular degeneration after antioxidant and zinc supplementation.
Disclaimer
From Sue and me: While there are other reputable laboratories offering AMD genetic screening, Arctic provides the only testing that gives advice on whether the AREDS supplements are helpful or harmful. We are only providing information about their testing. The final decision about any testing has to be made between you and your prescribing physician.