Eating a vegetarian diet can almost halve the risk of developing cancer, research suggests.

    A study of more than 61,000 individuals aged between 20 and 89 found those who did not eat meat reduced overall incidence of the disease by 12 per cent.

    But the most striking difference was in cancers of the blood, including leukaemia and non-Hodgkin lymphoma with 45 per cent fewer cases among the vegetarians.

    Research suggests there are 45 per cent fewer cases of leukaemia and non-Hodgkin lymphoma among vegetarians

    Tumours of the stomach and bladder were also significantly less frequent in this group.

    Professor Tim Key, a Cancer Research UK epidemiologist at the University of Oxford, said: 'Over a lifetime about one in three people will be diagnosed with cancer. So if 33 people in every hundred get cancer this would come down to about 29 with everyone following a vegetarian diet, which is 12 per cent lower.'

    However, Mr Key said the findings were not yet strong enough to advise the public to make dramatic changes to the way they eat as long as they are following an 'average balanced diet'.

    Although it is widely recommended we eat five portions of fruit and vegetables a day to reduce their risk of cancer and other diseases, there is little evidence looking specifically at a vegetarian diet.

    Mr Key, whose findings are published in the British Journal of Cancer, added: 'More research is needed to substantiate these results and to look for reasons for the differences.'

    His team followed the participants, just over half of whom were meat eaters, for more than 12 years during which time 3,350 were diagnosed with cancer. They looked at the rates of cancer among the vegetarians, and then compared them with those of the meat eaters.

    Mr Key said: 'Our study looking at cancer risk in vegetarians found the likelihood of people developing some cancers is lower among vegetarians than among people who eat meat.

    'In terms of what explains this we have to look at what other research is going on. For stomach cancer there is already quite alot of evidence that high intake of food such as processed meat may increase risk.

    'Obviously, vegetarians who are not eating meat would not have that risk factor. It could be something about being a vegetarian that is protective, or alternatively it could be something about meat actually increasing the risk.'

    Su Taylor, of the Vegetarian Society, said: 'This latest research adds to a growing body of evidence that vegetarians are less likely to get cancer.

    'It could be they are simply more likely to stick to the recommended five portions of fruit and vegetables a day, thereby eating more roughage, or it could be more complicated than this.'

    研究表明：素食可以把患癌癥的風險降低幾乎一半。

    研究者對61,000名，年齡20到89歲的人群進行調查，發現吃素的人群總體患癌癥比率率要低12%.

    最顯著的差異是血液系統疾病，素食者患上白血病和非霍奇金淋巴瘤只有45%.

    研究表明素食者患白血病和非霍奇金淋巴瘤的幾率只有45%.

    素食者患胃癌和膀胱癌明顯減少。

    英國牛津大學，英國癌癥研究所流行病學教授Tim Key說："世界總人口約三分之一的人可能患上癌癥。如果按比率每100人中有33人患有癌癥，那么，素食者這個比率會降到29%,而非素食者則達到了41%.

    KEY稱這個研究結果，還不足以勸告公眾痛下決心改變飲食習慣，讓他們以后均衡飲食。

    雖然建議大眾每天吃五份水果和蔬菜可以減少患癌癥和其他疾病的風險，但沒有充分的跡象表明有人在響應。

    在英國癌癥期刊的報告中KEY先生認為： "需要更多的研究來證實這些結果，并尋找產生差異的原因。"

    他的研究團隊觀注素食者與肉食者癌癥發病率，發現一半以上肉食人群中，吃肉超過12年的有3350人被診斷患有癌癥。KEY先生說： "我們的研究發現肉食者患癌癥的可能性要比素食者高。"

    這一現象應如何解釋？我們正關注其他正在進行的研究。已經有相當多的證據表明，例如吃加工過的肉食過多，可能會增加患胃癌的風險。很顯然，素食者不吃肉不會增加患癌的風險。這對素食者來說可能是很重要的保護，吃素之所以重要是因為吃肉確實越來越不安全。

    素食協會蘇。泰勒說： "最新研究顯示越來越多的證據---素食者不太可能患癌癥。他們可能堅持每天食用5份水果和蔬菜，并且吃更多的粗糧，也可能原因比這更復雜。"