Nimptsch Katharina, Wu Kana
Molecular Epidemiology Research Group, Max Delbrück Center for Molecular Medicine (MDC), Berlin, Germany.
Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA.
Curr Colorectal Cancer Rep. 2018 Feb;14(1):1-11. doi: 10.1007/s11888-018-0396-7. Epub 2018 Jan 18.
To summarize the current evidence on the most important dietary and lifestyle factors in colorectal carcinogenesis during different stages of a lifetime with special emphasis on studies investigating exposure during childhood, adolescence and young adulthood.
A number of studies showed that independent of adult obesity, higher body fatness during childhood, adolescence and young adulthood is associated with risk of colorectal cancer later in life. In one large cohort study, the Nurses' Health Study II, adherence to a western pattern diet during adolescence was associated with higher risk of advanced adenoma. The current evidence relating consumption of individual foods and nutrients as well as physical activity during early life to colorectal cancer is sparse and less consistent, at least in part due to limitations in study design, such as sample size, limited data on potential confounders or lack of a validated dietary assessment instrument.
As colorectal carcinogenesis is a long process and can take up to several decades to develop, early life risk factors may also be etiologically relevant. The recent rise in early-onset colorectal cancer incidence and mortality in the US, i.e., in individuals younger than 55 years at diagnosis, strongly supports that early life risk factors may influence colorectal carcinogenesis. Considering that the majority of colorectal cancers are preventable, there is an urgent need for well-designed investigations on the role of diet and lifestyle factors throughout the life course and risk of colorectal cancers.
总结一生中不同阶段结直肠癌发生过程中最重要的饮食和生活方式因素的现有证据，特别强调针对儿童期、青少年期和青年期暴露情况的研究。
多项研究表明，无论成人肥胖情况如何，儿童期、青少年期和青年期较高的体脂与日后患结直肠癌的风险相关。在一项大型队列研究“护士健康研究II”中，青少年时期坚持西式饮食模式与晚期腺瘤风险较高相关。目前关于生命早期个体食物和营养素的摄入以及身体活动与结直肠癌关系的证据稀少且不太一致，至少部分原因是研究设计存在局限性，如样本量、潜在混杂因素数据有限或缺乏经过验证的饮食评估工具。
由于结直肠癌发生是一个漫长的过程，可能需要数十年时间发展，生命早期的风险因素在病因学上也可能相关。美国近期诊断时年龄小于55岁的早发性结直肠癌发病率和死亡率上升，有力地支持了生命早期风险因素可能影响结直肠癌发生这一观点。鉴于大多数结直肠癌是可预防的，迫切需要针对饮食和生活方式因素在整个生命过程中的作用以及结直肠癌风险进行精心设计的研究。
