Diets rich in fat from red meat and dairy products can increase a person's risk of contracting cancer of the pancreas, researchers are warning.
Scientists at the National Cancer Institute in the United States asked more than half a million people to provide precise details of their diet over six years. The team found that those who consumed most animal fat had a higher risk of developing the cancer.
Pancreatic cancer is the 11th most common cancer in Britain. Around 7,600 people are diagnosed with it every year. For most, the prognosis is poor: only 2% to 3% survive for five years or more.
Smoking is rated as the biggest risk factor. While researchers have argued that diet is also involved, past studies have produced inconclusive results. However, Rachael Z. Stolzenberg-Solomon, leader of the institute's pancreatic cancer project, said the new study had revealed a clear association between pancreatic cancer risk and diet, in particular high levels of animal fat. "Reducing fat may reduce the risk of pancreatic cancer," she said.
The researchers collected data on 308,736 men and 216,737 women. Each completed a 124-item food questionnaire in 1995 and 1996.
During an average of six years of follow-up, 1,337 people were diagnosed with pancreatic cancer. Men who consumed the most fat from animal sources had a 53% increased risk of developing pancreatic cancer and women had a 23% increased risk, compared with men and women who ate the least fat, the study found.
In addition, it was discovered that people who ate high amounts of saturated fats had 36% higher rates of pancreatic cancer than did those who ate low amounts.
In a paper published by the Journal of the National Cancer Institute, Stolzenberg-Solomon said the researchers had observed positive associations between pancreatic cancer and intakes of total, saturated, and mono-unsaturated fat, particularly from red meat and dairy food sources.
"We did not observe any consistent association with poly-unsaturated or fat from plant food sources," she said. "Altogether, these results suggest a role for animal fat in pancreatic carcinogenesis."
The importance of the US study was underlined by Josephine Querido, senior science information officer for Cancer Research UK. "This large study adds to the evidence that pancreatic cancer is more common in people who eat too much fat, particularly saturated fat.
"Understanding ways of reducing the risk of pancreatic cancer is very important, because it can be very difficult to treat.
"Apart from stopping smoking, the best way to reduce your risk of cancer is to eat plenty of fruit, vegetables and fibre and to cut down on fatty foods, red and processed meat and limit your intake of alcohol."
高脂肪含量飲食增加罹患胰腺癌的風險
研究人員正在發出警告:攝入大量的富含脂肪的肉類和奶制品能增加人的罹患胰腺癌的可能。
在過去六年內,美國國立癌癥研究所的科學家們要求五十多萬人提供其飲食的具體情況,該研究小組發現消費大量動物脂肪的人群得癌癥的可能性更高。
胰腺癌在英國常見癌癥中位列11位,每年約有7600人診斷患有此病,而治愈狀況堪憂--僅2-3%能夠生命能持續5年及以上。
抽煙是最大的致癌因素。在研究者認為飲食也是其中一個誘因后,以往的研究的結果就有些不能使人信服了。然而,研究院的胰腺癌研究項目負責人莉秋Z.斯德森博格·索拉曼說,這項新的發現說明胰腺癌與飲食之間--尤其是高動物脂肪比例有著明顯的關系,"減少脂肪攝入就能降低患胰腺癌的風險。"
研究者收集了308,736位男性和216,737女性的數據,他們每個人都在1995-1996年度完成了124項的飲食調查問卷。
該研究發現,在連續的六年間,平均每年有1337人診斷患有胰腺癌,與攝入量最低的男性和女性相比,攝入動物脂肪量最高的男性患胰腺癌的風險增加了53%,而這一數字在女性中為23%.
另外,研究人員發現攝入高含量的飽和脂肪的群體,比那些攝入飽和脂肪量低的群體患有胰腺癌的可能高36%.斯德森博格·索拉曼在美國國立癌癥研究院的一份期刊中發表了一篇文章,她聲稱研究人員已經觀測到胰腺癌與飽和脂肪及單不飽和脂肪--尤其是那些從動物肉和奶源制品中攝入的的總量之間村子正相關性。
斯德森博格·索拉曼說,"尚未觀測到單不飽和脂肪或植物源的脂肪與患此癌癥的連續相關性,總的來講,這些結果表明了動物脂肪在引起此病的作用。"
美國的這份研究引起了英國癌癥研究所的資深科學信息官員杰森佛·克立德的重視,"這份大規模的研究提供了更多的證據,它證明了胰腺癌在攝入過量脂肪尤其是飽和脂肪的人群中更為常見。"
"理解降低此癌癥的風險的方式非常重要,因為此病很難治療。"
"除戒除抽煙以外,減少胰腺癌風險的最好方式就是多吃水果、蔬菜和纖維素,減少脂肪的攝入量,少吃生肉和加工肉和限制飲酒。"