牛奶雖好可別貪杯.

　　調(diào)研者稱，每天喝三杯以上牛奶非但不會幫你預(yù)防骨折，還可能導(dǎo)致更高的致死率。一項最新的研究表明，牛奶中包含的特定糖類會增加炎癥和氧化壓力，損壞身體細(xì)胞組織。然而在確定這一調(diào)查結(jié)果之前，瑞典調(diào)查者認(rèn)為還需要進(jìn)行更多的調(diào)查。

　　Milk is recommended for cutting the risk of fractures because it contains calcium and vitamin D,which are vital for bone strength. However, there have been conflicting results from studiesinto the health benits of milk in recent decades, with some showing it prevents heart attacksand strokes and others the opposite. Professor Karl Micha?lsson, Sweden, led a team toinvestigate whether the mechanism for potential harm was consumption of the sugarslactose and galactose found in high levels in milk, compared with much lower levels in other dairyproducts.

　　牛奶因其還有鈣質(zhì)和維生素D、可以預(yù)防骨折而被推薦飲用。然而近年來，牛奶的功效一直備受爭議。有人認(rèn)為牛奶可以預(yù)防心臟病和中風(fēng)，而又有人對此持反對意見。瑞典烏普薩拉大學(xué)卡爾教授帶領(lǐng)一個小組調(diào)查的內(nèi)容就是：和其他乳制品相比，牛奶中乳糖和半乳糖含量較高，而這是否會對人體造成潛在危害。

　　Two large groups of 61,433 women and 45,339 men in Sweden completed food frequencyquestionnaires for 96 common foods including milk, yoghurt and cheese. Women were trackedfor an average of 20 years, during which time 15,541 died and 17,252 had a fracture, of whom4,259 had a hip fracture. In women, drinking more milk did not cut the risk of broken bones,says the study published in The BMJ. Men were tracked for an average of 11 years, during whichtime 10,112 died and 5,066 had a fracture, with 1,166 hip fracture cases. Men who drankmore milk also had a higher risk of death, although much lower than in women.In contrast,eating more dairy products such as yoghurt and cheese - with a low lactose content – led tolower death rates and fewer fractures, particularly in women.

　　瑞典，共有61433名女性和45339名男性接受了關(guān)于攝入牛奶、優(yōu)格和乳酪頻率的問卷調(diào)查。關(guān)于女性的追蹤調(diào)查歷時20年，期間15541名女性過世，17252名女性曾骨折，其中4259名女性髖骨骨折。飲用牛奶并沒有降低女性骨折的風(fēng)險。而男性的調(diào)查則持續(xù)了11年，期間10112名男性過世，5066名男性骨折，其中1166名髖骨骨折。飲用更多牛奶的男性死亡率雖與女性相比較低，但仍舊高于牛奶攝入少的人群。相反，攝入乳糖含量較低的優(yōu)格或乳酪之類的乳制品死亡率更低，而且骨折風(fēng)險更小。

　　Prof Sue, Head of the Department of Nutritional Sciences, University of Surrey, said the studyhad limitations, such as weak methods to assess lifestyle habits including bodyweight. She said: ‘Also key is that all milk in Sweden is fortified with vitamin A. This may well be an importantconfounding factor. Milk and dairy products in the UK provide 50-60 percent of the calcium inour diet. We know that low calcium intakes is a risk factor for osteoporosis.’

　　薩里大學(xué)營養(yǎng)科學(xué)系主任蘇教授認(rèn)為這些調(diào)研都有其局限性，并不能準(zhǔn)確地評估包括體重等生活習(xí)慣。她說，“瑞典的牛奶中有加強(qiáng)補充維生素A，這可能也是關(guān)鍵因素之一。英國的牛奶和乳制品提供了日常營養(yǎng)攝入中50%~60%的鈣質(zhì)。而我們知道，低鈣攝入會導(dǎo)致骨質(zhì)疏松?！?/p>

　　Prof Brian Ratcliffe, Professor of Nutrition, Robert Gordon University, Aberdeen, said thepossible role of alcohol intake was understated given that most of the extra deaths in milkdrinkers were from heart disease. Lowest milk consumption was associated with the highestconsumption of alcohol, and ‘there is considerable evidence for a cardio-protective fect ofalcohol at modest intakes’ he said.

　　羅伯特戈登大學(xué)營養(yǎng)學(xué)布萊恩·雷德克里夫教授認(rèn)為，酒精攝入也應(yīng)劃入考慮范圍內(nèi)，因為研究中很多牛奶飲用者死于心臟疾病。低牛奶攝入和高酒精攝入是分不開的，而且“有可觀的證據(jù)表明，適量飲酒會保護(hù)心臟”。