VITAMINS & SUPPLEMENTS · GUIDE
Antioxidant Evidence by Use: Eye Health (AREDS2), Heart, Exercise, Skin and Aging
What trials found for antioxidant supplements in eye disease, heart disease, cancer, skin, exercise and aging, and why one tested eye formula is not "antioxidants" in general.
Content last updated . This page has not been medically reviewed.
Back to Antioxidants"Do antioxidants work?" bundles two different questions. One asks whether a specific formula, tested in a specific group of people, helped. The other asks whether antioxidant pills keep healthy people well. The first has an answer for one eye condition. For the second, the US National Center for Complementary and Integrative Health (NCCIH) says that, except for age-related macular degeneration, there is currently no evidence that antioxidant supplements have a positive impact on the diseases it reviewed, which included cancer, heart disease, cataracts and Alzheimer's disease. [1]
Eating more fruits and vegetables is a separate matter. MedlinePlus notes that it is not clear whether the benefit of those foods comes from the antioxidants, something else in the foods, or other factors. [2] Findings about foods do not transfer to pills. NCCIH lists reasons why: other substances in the foods, lifestyle differences, purified chemicals acting differently than food mixtures, and high supplement doses acting differently than the amounts in food. [1]
How to read the labels on this page
Each row below carries a plain label. Evidence in a defined group means a trial found benefit in a specific population and form. No good evidence of benefit means trials looked and did not find it. Evidence of harm means a trial or review found more of a bad outcome. Mixed, promising but limited and insufficient evidence mean what they say. "Proper evidence not found" means we looked and could not read a source that supports the claim.
Summary table
| Use | What the sources found | Label | Deeper page |
|---|---|---|---|
| Slowing intermediate age-related macular degeneration (AMD) | The NEI reports about a 25% lower risk of progression to advanced AMD with the tested AREDS and AREDS2 formulas. [3] A 2023 Cochrane review rated this moderate-certainty. [4] | Evidence in a defined group | More about Slowing intermediate age-related macular degeneration (AMD) → |
| Preventing AMD or cataract | Vitamin E or beta-carotene did not prevent AMD. [5] The tested formulas had no effect on cataract. [3] | No good evidence of benefit | More about Preventing AMD or cataract → |
| Preventing heart disease | The USPSTF recommends against beta-carotene or vitamin E for preventing cardiovascular disease or cancer. [6] | No good evidence of benefit; beta-carotene shows harm | More about Preventing heart disease → |
| Preventing cancer | Nine randomized trials reviewed by the National Cancer Institute did not show benefit. [7] | No good evidence of benefit; beta-carotene in smokers shows harm | More about Preventing cancer → |
| During chemotherapy or radiotherapy | Observational and review evidence raises concern that antioxidants may interfere. [8][9] | Insufficient evidence; caution | More about During chemotherapy or radiotherapy → |
| Exercise training | In small trials, vitamin C plus E blunted some training responses. [10][11] | Mixed | More about Exercise training → |
| Skin and sun damage | A 2025 review found the most photoprotection evidence for polyphenols and carotenoids, with small, short studies. [12] | Promising but limited | More about Skin and sun damage → |
| Memory and dementia risk | NCCIH describes two 2018 reviews with mixed, low-certainty results. [1] | Mixed | More about Memory and dementia risk → |
| Living longer | A Cochrane review found no evidence to support antioxidant supplements for prevention. [13] | No good evidence of benefit | More about Living longer → |
Eye health: a formula, not "antioxidants"
The National Eye Institute (NEI) ran AREDS and AREDS2 in people with age-related macular degeneration. AREDS2 enrolled people with intermediate AMD in both eyes, or intermediate AMD in one eye and advanced AMD in the other. [3] The trials tested vitamins C and E, zinc and copper with either beta-carotene (AREDS) or lutein and zeaxanthin (AREDS2). The NEI says the supplements reduce the risk of progression from intermediate to advanced AMD by about 25 percent, and do not prevent AMD onset. [3] The amounts are trial amounts for a defined group, not general advice. The NEI also says current and former smokers should avoid the version with beta-carotene, which increases lung cancer risk. [3]
Heart disease and cancer
The 2022 USPSTF statement covers community-dwelling, nonpregnant adults. It found the harms of beta-carotene outweigh the benefits and recommends against beta-carotene or vitamin E for preventing cardiovascular disease or cancer. For other single or paired nutrients it found the evidence insufficient. [6] A Cochrane review of 78 randomized trials with 296,707 participants found no evidence to support antioxidant supplements for primary or secondary prevention, and said beta-carotene and vitamin E seem to increase mortality. [13] The named trials behind these findings are described on the heart and cancer pages above.
Skin, exercise and aging
For skin, the evidence is early and mostly about sun-damage markers, not about replacing sun protection. For exercise, small trials of vitamin C plus E found blunted training responses in some measures, but one 11-week trial found no change in VO2 max or running performance. [11] Anti-aging claims are checked on the antioxidant myths page. Proper evidence not found, in the sources read for this page, that antioxidant supplements slow aging.
Frequently asked questions
What is the AREDS2 formula?
It is a specific combination of vitamins C and E, zinc, copper, lutein and zeaxanthin that the NEI tested in people with intermediate or one-eye advanced AMD. It is not a general antioxidant pill. [3]
Can AREDS2 supplements prevent macular degeneration?
The NEI says AREDS and AREDS2 supplements do not prevent AMD onset. [3]
Do antioxidant supplements prevent heart disease or cancer?
The USPSTF found no net benefit for vitamin E and found harms outweighed benefits for beta-carotene. It found the evidence insufficient for other single or paired nutrients. [6]
Do antioxidants help recovery after workouts?
Proper evidence not found in the sources read for faster recovery. Two small trials found vitamin C plus E blunted some training responses. [10][11]
Should I tell my doctor about antioxidant supplements?
Yes. Antioxidant supplements may interact with some medicines, and MedlinePlus advises telling your health care providers about any you use. [2]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Safety, in brief
High doses can cause harm: NCCIH says antioxidants can have harmful effects when taken at high doses. [1] High-dose vitamin E may raise bleeding risk, and a combination of vitamins E and C, selenium and beta-carotene reduced the effect of two cholesterol drugs in one study. [1] If you are pregnant or nursing, or considering a supplement for a child, NCCIH says it is especially important to consult a health care provider. [1] If you are being treated for cancer, tell your oncology team about every supplement. See medication interactions and talking with a health professional.
References
- National Center for Complementary and Integrative Health (NCCIH, US). Antioxidant Supplements: What You Need To Know. Read 2026-10-23.
- MedlinePlus (US National Library of Medicine). Antioxidants. Read 2026-10-23.
- National Eye Institute (US). AREDS/AREDS2 Clinical Trials, last updated October 22, 2025. Read 2026-10-23.
- Evans JR, Lawrenson JG. Antioxidant vitamin and mineral supplements for slowing the progression of age-related macular degeneration. Cochrane Database Syst Rev 2023. Read 2026-10-23.
- Evans JR, Lawrenson JG. Antioxidant vitamin and mineral supplements for preventing age-related macular degeneration. Cochrane Database Syst Rev 2017. Read 2026-10-23.
- US Preventive Services Task Force. Vitamin, Mineral, and Multivitamin Supplementation to Prevent Cardiovascular Disease and Cancer: Recommendation Statement. JAMA 2022. Read 2026-10-23.
- National Cancer Institute (US). Antioxidants and Cancer Prevention. Read 2026-10-23.
- Ambrosone CB et al. Dietary supplement use during chemotherapy and survival outcomes of patients with breast cancer enrolled in a cooperative group clinical trial (SWOG S0221). J Clin Oncol 2020. Read 2026-10-23.
- Limbrunner J et al. The influence of antioxidant supplementation on adverse effects and tumor interaction during radiotherapy: a systematic review. Clin Exp Med 2025. Read 2026-10-23.
- Ristow M et al. Antioxidants prevent health-promoting effects of physical exercise in humans. PNAS 2009. Read 2026-10-23.
- Paulsen G et al. Vitamin C and E supplementation hampers cellular adaptation to endurance training in humans. J Physiol 2014. Read 2026-10-23.
- Natarelli N et al. Oral supplements and photoprotection: a systematic review. J Med Food 2025. Read 2026-10-23.
- Bjelakovic G et al. Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases. Cochrane Database Syst Rev 2012. Read 2026-10-23.