A pilot study on clinicopathological features and intestinal microflora changes in colorectal cancer patients born over a nine-year period encompassing three years before and after the Great Chinese famine.

•We present a study on the impact of energy restriction on diversity within the gut microbiome and how this relates to colorectal cancer in a Chinese population.•Our study postulate that early life energy restriction influences the development and subsequent composition of the gut microbiome, which in turn influences the severity of outcomes after CRC diagnosis.•We have used a cohort of individuals born in the three years prior to the great leap forward famine (GLFF), during the GLFF and in the three years after the GLFF. The study uses a unique, population wide event to identify the impact of energy restriction during early life development.