Antioxidant

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An antioxidant is a molecule capable of slowing or preventing the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons from a substance to an oxidizing agent. Oxidation reactions can produce free radicals, which start chain reactions that damage cells. Antioxidants terminate these chain reactions by removing free radical intermediates, and inhibit other oxidation reactions by being oxidized themselves. As a result, antioxidants are often reducing agents such as thiols, ascorbic acid or polyphenols.

Although oxidation reactions are crucial for life, they can also be damaging; hence, plants and animals maintain complex systems of multiple types of antioxidants, such as glutathione, vitamin C, and vitamin E as well as enzymes such as catalase, superoxide dismutase and various peroxidases. Low levels of antioxidants, or inhibition of the antioxidant enzymes, causes oxidative stress and may damage or kill cells.

As oxidative stress might be an important part of many human diseases, the use of antioxidants in pharmacology is intensively studied, particularly as treatments for stroke and neurodegenerative diseases. However, it is unknown whether oxidative stress is the cause or the consequence of disease. Antioxidants are also widely used as ingredients in dietary supplements in the hope of maintaining health and preventing diseases such as cancer and coronary heart disease. Although initial studies suggested that antioxidant supplements might promote health, later large clinical trials did not detect any benefit and suggested instead that excess supplementation may be harmful. In addition to these uses of natural antioxidants in medicine, these compounds have many industrial uses, such as preservatives in food and cosmetics and preventing the degradation of rubber and gasoline.

For more information about Antioxidant, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with antioxidants

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Chocolate

Chocolate rich in flavanols may protect the skin from UV

Medicine & Health / Health

created Nov 06, 2009 | popularity 5 / 5 (9) | comments 3

(PhysOrg.com) -- A new study has discovered for the first time that dark chocolate rich in flavanols may provide significant protection from the harmful effects of ultraviolet light.


Curry-cure? Spicing up the effectiveness of a potential disease-fighter

Curry-cure? Spicing up the effectiveness of a potential disease-fighter

Chemistry / Other

created Nov 04, 2009 | popularity 4 / 5 (2) | comments 0

Scientists are reporting development of a nano-size capsule that boosts the body's uptake of curcumin, an ingredient in yellow curry now being evaluated in clinical trials for treatment of several diseases. ...


Dietary patterns linked with depression

Processed, high-fat foods linked with depression

Medicine & Health / Psychology & Psychiatry

created Nov 02, 2009 | popularity 2.6 / 5 (5) | comments 3

(PhysOrg.com) -- People who eat a diet laden with processed and high-fat foods may put themselves at greater risk of depression, according to UCL (University College London) research published today.


Scientists discover influenza's Achilles heel: Antioxidants

Biology / Cell & Microbiology

created Oct 29, 2009 | popularity 4.3 / 5 (7) | comments 1

As the nation copes with a shortage of vaccines for H1N1 influenza, a team of Alabama researchers have raised hopes that they have found an Achilles' heel for all strains of the flu—antioxidants. In an article appearing in ...


Scientists identify roots of diabetic tissue damage

Medicine & Health / Research

created Oct 22, 2009 | popularity 4.7 / 5 (3) | comments 0

(PhysOrg.com) -- Results from comprehensive assessments of diabetes' effects on cell metabolism may aid efforts to reduce diabetic damage to nerves, blood vessels and other tissues, according to researchers at Washington ...


Could antioxidants make us more, not less, prone to diabetes? Study says yes

Medicine & Health / Research

created Oct 06, 2009 | popularity 2.7 / 5 (10) | comments 0

We've all heard about the damage that reactive oxygen species (ROS) - aka free radicals - can do to our bodies and the sales pitches for antioxidant vitamins, skin creams or "superfoods" that can stop them. In fact, there ...


Higher folates, not antioxidants, can reduce hearing loss risk in men

Medicine & Health / Health

created Oct 05, 2009 | popularity 5 / 5 (3) | comments 0

Increased intakes of antioxidant vitamins have no bearing on whether or not a man will develop hearing loss, but higher folate intake can decrease his risk by 20 percent, according to new research presented at the 2009 American ...


Eat soybeans to prevent diseases

Biology / Other

created Sep 29, 2009 | popularity 3.5 / 5 (2) | comments 0

Soybeans contain high levels of several health-beneficial compounds including tocopherols, which have antioxidant properties. These molecules can be used in the development of functional foods, which have specific health-beneficial ...


Antioxidant controls spinal cord development

Medicine & Health / Neuroscience

created Sep 18, 2009 | popularity 4.9 / 5 (7) | comments 0

Researchers at the Johns Hopkins School of Medicine have discovered how one antioxidant protein controls the activity of another protein, critical for the development of spinal cord neurons. The research, publishing this ...


High fruit and vegetable intake positively correlated with antioxidant status, cognitive performance

Medicine & Health / Diseases

created Sep 09, 2009 | popularity 4.5 / 5 (2) | comments 0

Researchers at the Institute of Biochemistry and Molecular Biology I of the Heinrich-Heine University, Düsseldorf, Germany, investigated the relationship between fruit and vegetable intake, plasma antioxidant micronutrient ...


Powerful new 'molecular GPS' helps probe aging and disease processes

Chemistry / Biochemistry

created Sep 02, 2009 | popularity not rated yet | comments 0

Scientists in Michigan are reporting the development of a powerful new probe for identifying proteins affected by a key chemical process important in aging and disease. The probe works like a GPS or navigation system for ...


Whole grain cereals, popcorn rich in antioxidants, not just fiber, new research concludes

Whole grain cereals, popcorn rich in antioxidants, not just fiber: study

Medicine & Health / Health

created Aug 18, 2009 | popularity 4.4 / 5 (8) | comments 4

In a first-of-its kind study, scientists reported today at the 238th National Meeting of the American Chemical Society (ACS) that snack foods like popcorn and many popular breakfast cereals contain "surprisingly ...


Naturally occurring protection against severe malaria

Medicine & Health / Research

created Aug 17, 2009 | popularity 4.5 / 5 (2) | comments 0

In a study to be published in the next issue of the Proceedings of the National Academy of Sciences (PNAS), researchers at the Instituto Gulbenkian de Ciência, in Portugal, show that an anti-oxidant drug can protect again ...


Researcher has uncovered a way to provide antioxidant-rich water in a bottle

Chemistry / Other

created Jul 31, 2009 | popularity 3 / 5 (3) | comments 1

(PhysOrg.com) -- Health-conscious consumers know the benefits of eating high-antioxidant foods like fruits, vegetables, beans and nuts. A University of Georgia researcher has uncovered a way to provide antioxidant-rich water ...


Freshly crushed garlic better for the heart than processed

Freshly crushed garlic better for the heart than processed

Chemistry / Biochemistry

created Jul 29, 2009 | popularity 4 / 5 (3) | comments 0

A new study reports what scientists term the first scientific evidence that freshly crushed garlic has more potent heart-healthy effects than dried garlic. Scheduled for the Aug. 12 issue of the Journal of ...