VITAMINS & SUPPLEMENTS · GUIDE
Antioxidant Categories: Vitamins, Minerals, Carotenoids, Polyphenols and Others
A plain guide to the main kinds of antioxidants, vitamins, minerals, carotenoids, polyphenols and others, with a map to the page on each and a caution on what the label means.
Content last updated . This page has not been medically reviewed.
Back to AntioxidantsEvidence labels used in this library: established nutritional role, evidence in adequately nourished people, promising but limited, mixed, insufficient evidence, no good evidence of benefit, evidence of harm, preclinical, marketing claim.
The main categories
| Category | Examples named in the sources | What to know | Where covered |
|---|---|---|---|
| Vitamins | Vitamin C, vitamin E; vitamin A and beta-carotene [1] | Antioxidant activity is one role among others. Cochrane found beta-carotene and vitamin E seemed to increase mortality in trials. [3] | More about Vitamins → |
| Minerals (as enzyme parts) | Selenium, zinc, copper, manganese | NCI says selenium's antioxidant effects are most likely due to selenium-containing proteins. [1] | More about Minerals (as enzyme parts) → |
| Carotenoids | Beta-carotene, lycopene, lutein [4] | High-dose beta-carotene may raise lung cancer risk, mainly in smokers and people with asbestos exposure. [2] | More about Carotenoids → |
| Polyphenols and flavonoids | Quercetin, anthocyanins, epicatechin [4] | A 2000 review said phenolics or polyphenolics account for most of the antioxidant capacity in fruits, vegetables and most botanical supplements. [5] | More about Polyphenols and flavonoids → |
| Body-made molecules | Glutathione [4] | Made in the body; oral, liposomal and injected forms differ. | More about Body-made molecules → |
| Other compounds sold as antioxidants | Coenzyme Q10, alpha-lipoic acid | Listed in this library; whether a given effect comes from antioxidant activity is judged on each page. | CoQ10, alpha-lipoic acid |
| Enzymes | Superoxide dismutase, catalase, glutathione peroxidase | The body's own; the NCCIH calls antioxidant enzymes the most important part of the defense. [2] | More about Enzymes → |
Why the category label can mislead
Test-tube activity is not clinical effect. A review concluded that total antioxidant capacity values for foods cannot be translated to the body's defenses or to health effects. [6]Small-molecule antioxidants have limited power inside the body. A 2024 review states that vitamins C and E, flavonoids and carotenoids provide only limited protection against free radical damage in biological systems. [4] A 2015 review adds that the major role in defense is fulfilled by enzymes. [7]
Some compounds work in other ways. Whether a compound's studied effect is related to antioxidant activity is not settled by its being on an "antioxidant" list. Berberine and curcumin are filed here, and their pages address what the research does and does not show. See berberine and curcumin supplements.
Forms are not interchangeable. Results for one form should not be carried to another, for example beta-carotene vs the carotenoids in food, or one vitamin E form vs another. The NCCIH says different antioxidants may not be interchangeable. [2]
What trials found, by category
Antioxidant supplements and mortality
Evidence of harm for some; none of benefit78 randomized trials, 296,707 participants: no evidence to support prevention use; beta-carotene and vitamin E seemed to increase mortality, vitamin C and selenium did not significantly affect it in low-risk-of-bias trials. [3]
Cancer prevention trials
No good evidence of benefit; harm signalsNine randomized trials of antioxidant supplements did not provide evidence of benefit; ATBC and CARET showed more lung cancer with beta-carotene; SELECT showed more prostate cancer with vitamin E alone. [1]
Age-related macular degeneration
Specific formulas onlyCombinations of antioxidants and zinc used in AREDS and AREDS2 may slow progression in people who already have the disease. [2]
Read the detail on evidence by use and high-dose risks by compound.
Frequently asked questions
What are the main types of antioxidants?
NCI names beta-carotene, lycopene and vitamins A, C and E, and notes selenium's effects are likely through selenium-containing proteins. [1] Polyphenols, glutathione and enzymes are also described in the sources. [4]
Are all antioxidants the same?
No. Each of the many antioxidants in the body has different properties, and they may not be interchangeable. [2]
Which antioxidant is best?
Proper evidence not found for a best antioxidant. We looked at NCI, NCCIH and a Cochrane review; none ranks them, and evidence differs by compound and population. [2][3]
Do antioxidant foods and antioxidant supplements count as the same category?
They share a label, but evidence differs. Fruit and vegetable intake is linked with lower disease risk in observational studies, while supplements have not shown the same benefit. [2]
Where is each antioxidant covered on this site?
See the table above, or the A to Z ingredient guide.
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 and who should ask a clinician
References
- Antioxidants and Cancer Prevention. National Cancer Institute (US). Read 2026-10-23.
- Antioxidant Supplements: What You Need To Know. National Center for Complementary and Integrative Health (US). 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.
- Jomova K, et al. Several lines of antioxidant defense against oxidative stress. Arch Toxicol 2024 (full text read via PubMed Central). Read 2026-10-23.
- Prior RL, Cao G. Analysis of botanicals and dietary supplements for antioxidant capacity: a review. J AOAC Int 2000. Read 2026-10-23.
- Fraga CG, et al. In vitro measurements and interpretation of total antioxidant capacity. Biochim Biophys Acta 2014. Read 2026-10-23.
- Sies H. Oxidative stress: a concept in redox biology and medicine. Redox Biol 2015. Read 2026-10-23.