A diet low in salt and meat can dramatically reduce the risk of kidney stones, according to an Italian study that could spell the end for the low-calcium diet that doctors have been recommending for years.
About 10% of the U.S. population - and a much larger percentage of men, who make up 80% of sufferers - will have at least one kidney stone sometime in their lives, and it can be excruciatingly painful. Most stones can be excreted, but in about 15% of cases, surgery or shockwave treatment to pulverize the stones is needed.
據意大利的一項研究表明,低鹽低肉飲食可以顯著降低患腎結石的危險,該研究還"終結"了醫生已推薦了多年的防腎結石低鈣飲食。?
美國人口中約有10%至少在一生中某時間患有一側腎結石,其中男性比例要高得多,占患者的80%,患者有難以忍受的疼痛。大多數腎結石能排掉,但有大約15%的病例,需要動手術或用沖擊波治療才能粉碎腎結石。
Many doctors have told such patients to cut down on calcium because most kidney stones are made of a calcium compound. But recent studies have suggested that such a diet might not prevent kidney stones after all and may even promote them - along with osteoporosis.
The new study "dispelled a myth that a low-calcium diet is important in preventing kidney stones," said Dr. David A. Bushinsky, a kidney specialist at the University of Rochester.
許多醫生曾告訴這些患者減少鈣的攝入,因為大多數腎結石的成份是鈣。但是最近的研究已表明,低鈣飲食不僅不能預防腎結石,甚至會促使它的生成,還伴有骨質疏松。
羅切斯特大學的腎病專家David A.Bushinsky博士說:"這項新研究打破了低鈣飲食對防腎結石十分重要的神話。" ?
William Keane, president of the National Kidney Foundation, said he is sure the new diet "will become the gold standard."
Dr. Umberto Maggiore, explained that people on a low-calcium diet excrete less calcium in their urine but more of the other substance that combines with calcium to form most kidney stones.
In addition, salt and one protein common in meat lead to more calcium in the urine, which in turn contributes to the formation of kidney stones, Bushinsky said.
The low-salt, low-protein diet allowed 2,900 milligrams of salt per day; 2,400 is the maximum recommended by the American Heart Association. But people were allowed only about three-quarters of an ounce of meat per day, with just over an ounce of cheese or other dairy protein.
全國腎臟基金會主席William Keane說他確信新的飲食"將成為金標準"。
Umberto Magiore博士解釋說,低鈣飲食者雖在尿中只排出少量的鈣,但多數與鈣結合的其它物質形成了大部分腎結石。
Bushinsky說,此外,鹽和肉中的常見蛋白質導致尿中有較多的鈣,這樣就促使腎結石的形成。
低鹽低蛋白飲食允許每天攝入鹽2,900毫克,美國心臟學會推薦的最大量是2,400毫克。而且人們每天只能攝入四分之三盎司的肉,和一盎司多一點的奶酪或其它乳蛋白。?
The American Foundation for Urologic Disease does not mention a low-calcium diet on its Web page about kidney stones, but does say a doctor may suggest a low-meat, low-salt diet. The National Kidney Foundation's Web page says a doctor may suggest either diet, depending on test results.
Health care for kidney stones added up to $1.8 billion in 1993, according to the National Institute of Diabetes and Digestive and Kidney Diseases. Drinking 10 to 12 big glasses of water during the day can keep stones from forming and push out those smaller than a pea.
美國泌尿系統病基金會在它的網頁上尚沒有提及低鈣飲食和腎結石關系,但該網頁說醫生應推薦低肉低鹽飲食。全國腎臟基金會的網頁說醫生應根據檢驗結果推薦飲食。
據全國糖尿病、消化和腎病研究所介紹,用于腎結石的醫療保健費用在1993年就達到180億美元。一天中喝10至20大杯水能阻止腎結石的形成,排出比豌豆還小的腎結石。