[营养与癌症]

Institut für Sozial- und Präventivmedizin, Universität Zürich.

Ther Umsch. 2000 Mar;57(3):146-51. doi: 10.1024/0040-5930.57.3.146.

The complex process of carcinogenesis is mainly due to environmental factors and therefore preventable. Diet may account for about 35% of cancer. This review presents the nutritional evidence for the development of the four most common cancers in Switzerland. The clearest risk factors for breast cancer are those associated with hormonal and reproductive factors. In relation to dietary factors, high alcohol intake, weight gain and adipositas (postmenopausal breast cancer) probably increase the risk of breast cancer. The evidence is less clear for the consumption of (animal) fat, meat, fruit and vegetables (inverse association). Hormones may also play an important role in the development of prostate cancer. There is no convincing evidence that any dietary factors modify the risk of prostate cancer. Diets high in vegetables are possibly protective, regular consumption of fat and meat possibly increase the risk. Intervention trials revealed protective effects of supplementation with selen or alpha-tocopherol. The main cause of lung cancer is cigarette smoking, and smokers whose diet is protective nevertheless remain at high risk. The evidence that diets high in vegetables and fruit protect against lung cancer is convincing, but it is not clear what constitutents are responsible for this effect. Intervention trials revealed no protective effect of beta-carotene, and in high risk groups, lung cancer risk was even increased. There is convincing evidence that diets high in vegetables decrease the risk of colorectal cancer. The same is true for regular physical activity. Alcohol and consumption of diets high in (red) meat, probably increase the risk of colorectal cancer. For cancer prevention it is recommended to choose a predominantly plant-based diet, to avoid obesity, to reduce the intake of fat, (red) meat, alcohol and salt, not to smoke and to be physically active. The main aim of nutritional therapy of cancer patients is to improve quality of life, whereas the effect on life expectancy is very limited.

致癌的复杂过程主要归因于环境因素，因此是可预防的。饮食可能占癌症病因的35%左右。本综述介绍了瑞士四种最常见癌症发病的营养证据。乳腺癌最明确的风险因素是与激素和生殖因素相关的因素。就饮食因素而言，高酒精摄入量、体重增加和肥胖（绝经后乳腺癌）可能会增加患乳腺癌的风险。关于（动物）脂肪、肉类、水果和蔬菜的消费（呈负相关），证据尚不明确。激素在前列腺癌的发病过程中可能也起重要作用。没有令人信服的证据表明任何饮食因素会改变前列腺癌的风险。高蔬菜饮食可能具有保护作用，经常食用脂肪和肉类可能会增加风险。干预试验显示补充硒或α-生育酚具有保护作用。肺癌的主要病因是吸烟，饮食具有保护作用的吸烟者仍然处于高风险状态。高蔬菜和水果饮食可预防肺癌的证据令人信服，但不清楚是哪些成分起了这种作用。干预试验显示β-胡萝卜素没有保护作用，在高风险人群中，肺癌风险甚至增加。有令人信服的证据表明高蔬菜饮食可降低患结直肠癌的风险。经常进行体育活动也有同样的效果。酒精和高（红）肉饮食可能会增加患结直肠癌的风险。为预防癌症，建议选择以植物为主的饮食，避免肥胖，减少脂肪、（红）肉、酒精和盐的摄入量，不吸烟并积极进行体育活动。癌症患者营养治疗的主要目的是提高生活质量，而对预期寿命的影响非常有限。