Antioxidant-Rich Foods: What They Contain and What Research Shows
Which everyday foods contain antioxidant-type nutrients and plant compounds, what large reviews found about eating more of them, and why that does not carry over to pills.
Content last updated . This page has not been medically reviewed.
Fruits, vegetables, nuts, seeds and plant oils all contain compounds called antioxidants, and eating more fruit and vegetables is linked with better health in large studies. Antioxidant supplements have not shown the same benefit in the trials we read. [1] This page covers what is in the foods, what the research says, and what it cannot tell us.
What "antioxidant-rich" can mean
"Antioxidant" is a description of what a compound does in a test tube, not one nutrient. Foods supply several different groups:| Group | Foods named by the source | Source |
|---|---|---|
| Vitamin C | Citrus fruit, peppers, strawberries, blackcurrants, broccoli, Brussels sprouts, potatoes | NHS (UK) [2] |
| Vitamin E | Plant oils, nuts and seeds, wheatgerm | NHS (UK) [3] |
| Beta-carotene (a carotenoid the body can turn into vitamin A) | Yellow and green (leafy) vegetables such as spinach, carrots, red peppers; yellow fruit such as mango, papaya, apricots | NHS (UK) [4] |
| Selenium (a mineral used by the body's antioxidant enzymes) | Brazil nuts, fish, meat, eggs | NHS (UK) [4] |
| Polyphenols (plant pigments and other phenolic compounds) | Fruits, vegetables and botanicals; polyphenols account for most of their measured antioxidant capacity | 2000 review [5] |
Detail on each: vitamin C, vitamin E, carotenoids and selenium. Food pages worth a look: blueberries, tomatoes, leafy greens and walnuts.
What research shows about eating them
How much, and how it is prepared
- Intake advice (UK NHS): at least 5 portions of a variety of fruit and vegetables a day; a portion is 80 g. [8] The NHS notes that the advice is based on the World Health Organization recommendation of at least 400 g a day. [8]
- Variety: the NHS says different fruits and vegetables contain different combinations of fibre, vitamins, minerals and other nutrients. [8]
- Fresh, frozen, canned, dried or juiced: the NHS counts all of these. [8] Juice has limits; see antioxidant drinks, juices and powders.
- Carotenoid absorption: a 2000 review found beta-carotene from vegetables is less available than purified beta-carotene added to a simple food. It also found that a small amount of fat with a meal (about 3-5 g) seems enough to support carotenoid absorption, and that mechanical homogenizing or heat treatment can raise the availability of carotenoids from vegetables. [9]
Frequently asked questions
Which foods are highest in antioxidants?
There is no single list. Different foods supply different groups of these compounds, and the NHS says different fruits and vegetables contain different combinations of nutrients. [8] ORAC-style scores are test-tube numbers; see the ORAC myth.
Is it better to eat antioxidants than to take them?
For general health, the evidence we read favors food. Large reviews link fruit and vegetable intake with lower risk, while NCCIH finds no evidence of benefit from supplements outside macular degeneration. [6] [1]
How many portions of fruit and vegetables does the NHS recommend?
At least 5 portions of a variety a day, with a portion being 80 g. [8] Other countries' advice may differ.
Does cooking destroy antioxidants?
The source we read on carotenoids found heat treatment or homogenizing can raise their availability from vegetables. [9] We did not read a general source on cooking and every antioxidant, so we do not make a blanket claim.
Can antioxidant-rich foods be harmful?
The sources we read describe harm from supplements (beta-carotene in smokers), not from foods. [4] If you take medicines, have kidney disease or are having cancer treatment, ask your clinician or pharmacist about large diet changes.
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.
How to read the evidence labels
Labels used on this page: "evidence in adequately nourished people" means the finding comes from studies in general populations; "no good evidence of benefit" means trials of supplements did not show a benefit; "evidence of harm" means a trial or review reported harm.
| Question | What the source found | Strength of evidence |
|---|---|---|
| Is eating more fruit and vegetables linked with lower risk? | A review of prospective studies (95 studies) found risk reductions up to 800 g/day for most outcomes. For all-cause mortality the summary relative risk per 200 g/day was 0.90 (95% CI 0.87-0.93). [6] | Observational. It shows association, not proof of cause |
| Do antioxidant supplements give the same result? | NCCIH (US) says that, except for age-related macular degeneration, there is no evidence that antioxidant supplements help with cancer, heart disease or other conditions studied. [1] | No good evidence of benefit |
| Does a specific supplement formula help in eye disease? | NCCIH says certain supplements combining antioxidants and zinc were shown to slow progression of macular degeneration. [1] See AREDS and AREDS2 results. | Trial evidence for one formula and one condition. Do not transfer to other products |
| Do supplements affect death rates? | A Cochrane review of 78 randomized trials (296,707 people) tested beta-carotene, vitamin A, vitamin C, vitamin E and selenium. [7] The overall random-effects result showed no significant effect on mortality, but in the 56 low-risk-of-bias trials the supplements significantly increased mortality. [7] | Evidence of harm in a subset of trials |
Why might food and pills differ? NCCIH says the benefits seen with a diet high in vegetables and fruits may be due to other substances in those foods or other aspects of people's lifestyles, and that purified antioxidants may act differently from those in foods. [1] See antioxidant evidence by use.
Cautions
- Smokers and people exposed to asbestos: NHS (UK) says beta-carotene supplements have been found to increase lung cancer risk in people who smoke. [4] A review of smoking trials links the harm to smoking status. [10] This concerns supplements. The NHS says there is no evidence that the beta-carotene we get from food is harmful. [4]
- Cancer treatment: NCCIH says antioxidants might reduce the effectiveness of some cancer treatments. [1] Ask your oncology team before adding supplements. Food questions during treatment are for your care team too.
- Special diets: if a clinician has told you to limit certain foods (for example because of kidney disease or a medicine), follow that advice and ask about changes.
- Do not replace care: NCCIH advises against using antioxidant supplements as a reason to postpone seeing a health care provider. [1]
Related: food-first nutrition and what are functional foods?
References
- Antioxidant Supplements: What You Need To Know. National Center for Complementary and Integrative Health (US), last updated July 2023. Read 2026-10-23.
- Vitamins and minerals: Vitamin C. NHS (UK), page last reviewed 2020. Read 2026-10-23.
- Vitamins and minerals: Vitamin E. NHS (UK), page last reviewed 2020. Read 2026-10-23.
- Vitamins and minerals: Others (beta-carotene, selenium and more). NHS (UK). Read 2026-10-23.
- Analysis of botanicals and dietary supplements for antioxidant capacity: a review. Journal of AOAC International, 2000. Read 2026-10-23.
- Fruit and vegetable intake and the risk of cardiovascular disease, total cancer and all-cause mortality: a systematic review and dose-response meta-analysis of prospective studies. International Journal of Epidemiology, 2017. Read 2026-10-23.
- Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases. Cochrane Database of Systematic Reviews, 2012. Read 2026-10-23.
- Why 5 A Day? NHS (UK), page last reviewed September 2026. Read 2026-10-23.
- Dietary factors that affect the bioavailability of carotenoids. The Journal of Nutrition, 2000. Read 2026-10-23.
- Beta-carotene and lung cancer in smokers: review of hypotheses and status of research. Nutrition and Cancer, 2009. Read 2026-10-23.