This natural chemical is known to have anti-oxidant effects, which may protect against heart disease and cancer.

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Ann Foster:For example to improve nutritional content of food, to increase the anti-oxidant content of fruit and vegetables.

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Most of their oxidant, in the form of oxygen, comes from the atmosphere.

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Tomatoes are rich in lycopene, a powerful anti-oxidant which, according to the American Dietic Association, reduces the risk of prostate cancer and cardiovascular disease.

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This means they do not have to carry liquid oxygen (or some other oxidant) to burn their fuel, and could thus use the weight saved to carry a bigger payload.

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