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Reference Terms
from Wikipedia, the free encyclopedia

Antioxidant

An antioxidant is a chemical that reduces the rate of particular oxidation reactions in a specific context, where oxidation reactions are chemical reactions that involve the transfer of electrons from a substance to an oxidizing agent, this generally results in different chemicals to the original ones.

Antioxidants are particularly important in the context of organic chemistry and biology. All living organisms maintain a reducing environment inside their cells, all cells contain complex systems of antioxidants to prevent chemical damage to the cells' components by oxidation. These antioxidants include glutathione and ascorbic acid and are substrates for enzymes such as peroxidases and oxidoreductases.

Antioxidants are widely used as ingredients in dietary supplements used for health purposes such as preventing cancer and heart disease. Studies have suggested antioxidant supplements has benefits for health, but several large clinical trials did not demonstrate a definite benefit for the formulations tested, and excess supplementation may even be harmful.

Dietary supplementation has few specific antioxidants compared to a broad diet rich in phytonutrients, which will yield thousands of different polyphenol antioxidants available for metabolism.

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June 2, 2026

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A major study suggests that some of the groundwork for brain development may be shaped before birth through a surprising partnership between a baby’s genes and gut microbes. Researchers found that ...
A surprising new study suggests that when it comes to pancreatic cancer, the kind of fat you eat may matter more than how much. Researchers found that oleic acid—the main fat in olive oil and several other common foods—sped up tumor growth in ...
A Salk Institute study found that a simple dietary amino acid, methionine, dramatically improved survival in mice facing severe infections and inflammatory conditions. Rather than directly targeting the immune system, methionine boosted kidney ...
A promising new study suggests rheumatoid arthritis may not be as inevitable as once thought for people at high risk. Researchers found that just one year of treatment with the immune-targeting drug abatacept delayed the onset of rheumatoid ...
A long-overlooked organ may hold surprising clues to healthy aging and cancer survival. Researchers at Mass General Brigham used AI to analyze CT scans from tens of thousands of adults and found that people with healthier thymuses—a small ...
Scientists at Scripps Research have uncovered a molecular “switch” that appears to fuel the damaging brain inflammation seen in Alzheimer’s disease. They found that a protein called STING becomes chemically altered in a way that keeps the ...
Melanoma may not become steadily more dangerous with age as scientists once assumed. In a surprising discovery, researchers found that cancer spread was lowest in young mice, surged in middle-aged mice, and then dropped again in very old mice. The ...
Losing weight may involve rewiring the gut and the brain at the same time. In a study of obese adults, an intermittent fasting-style diet led to significant weight loss, healthier metabolic markers, and notable shifts in gut bacteria. Brain scans ...
A new study suggests fish oil may help reduce insulin resistance even in people who aren't obese. In diabetic rats, omega-3 supplementation improved blood sugar levels, cholesterol, and inflammation by shifting immune cells into a more ...
A new study suggests melatonin supplements may help night shift workers boost their body's DNA repair processes, potentially offsetting some of the damage linked to working overnight. The findings ...
A specially formulated tomato-soy juice packed with natural plant compounds may help calm inflammation linked to obesity, according to a new clinical study. Healthy adults with obesity who drank the juice daily for four weeks saw significant ...

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