Eating steamed broccoli reduces the risk of a heart attack by boosting the body's ability to fight off cell damage, researchers have found. Previous studies have found people who eat broccoli, especially if raw or lightly cooked, are at lower risk of heart disease and some cancers. Now scientists have found a clear link between high levels of certain substances found in the vegetable and reduced damage caused by hearts being deprived of oxygen. Normal biological processes associated with eating and breathing lead to the generation of highly reactive chemicals called free radicals. Excessive production of free radicals can harm cells and even trigger cancers. Damage of this type is known to accumulate with age. But the brassica family of vegetables, including cauliflower, broccoli, cabbage and Brussels sprouts, provide antioxidants that prevent the build-up of free radicals. Broccoli in particular contains sulforaphane, which triggers production of proteins that are part of the body's cardiovascular defence system. While researchers have long believed antioxidant substances have health benefits, many studies have failed to show an effect. The new study, published in the Journal of Agricultural and Food Chemistry, shows a specific mechanism in tests on animals. Prof Dipak Das, the director of the cardiovascular research centre at the University of Connecticut, fed steamed broccoli extract to rats for one month and measured its effects on their hearts. Compared with rats on a normal diet, those fed the broccoli extract had improved heart function and less damage when deprived of oxygen. Prof Das found these effects were caused by the broccoli diet triggering increased production of several proteins that maintain the heart's ability to function healthily. Prof Das said: "We are increasingly finding that 'redox proteins', which counter the effects of oxidisation, have an important role in the body's defence against heart disease. "However, if broccoli is over-cooked it loses a lot of its protective effect." Prof Das's team is investigating whether the antioxidants in broccoli and other cruciferous vegetables also play important roles in fighting other diseases. Secrets of celeery revealed Cooks have long marvelled at how the tasteless celery can add flavour to a dish. Now scientists claim they have unlocked the secret of how the versatile vegetable improves dishes, such as soups, stews and risottos. Celery is so popular that Britons eat 120 million sticks a year. Researchers in Japan have identified three chemical compounds in celery that adopt a sweet-spicy flavour of their own after boiling, helping give meals a thick, full-bodied taste. It is now hoped the compounds, known as phthalides, could be used in processed foods. The discovery by Kikue Kubota and colleagues at the Japanese firm T Hasegawa was reported in the Journal of Agricultural and Food Chemistry. | 
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