Diet is one of the most affective environmental factors in cancer development. Due to complicated nature of the diet, it has been very difficult to provide clear explanations for the role of dietary components in carcinogenesis. However, as high-throughput omics techniques became available, researchers are now able to analyze large sets of gene transcripts, proteins, and metabolites to identify molecules involved in disease development. Bioinformatics uses these data to perform network analyses and suggest possible interactions between metabolic processes and environmental factors. Obesity is known as one of the most closely related risk factors of colorectal cancer (CRC). Metabolic disturbances due to a positive energy balance may trigger and accelerate CRC development. In this review, we have summarized reports on genes, proteins and metabolites that are related to either obesity or CRC, and suggested candidate molecules linking obesity and CRC based on currently available literature. Possible application of bioinformatics for a large scale network analysis in studying cause-effect relationship between dietary components and CRC are suggested.