The study, which is the first to identify the interactions of genes and diet on a genome-wide scale, also revealed another specific genetic variation that appears to modify whether eating more vegetables, fruits and fibre actually lowers your colorectal cancer risk.
"Diet is a modifiable risk factor for colorectal cancer. Our study is the first to understand whether some individuals are at higher or lower risk based on their genomic profile. This information can help us better understand the biology and maybe in the future lead to targeted prevention strategies," lead author Jane Figueiredo from Keck School of Medicine of USC said.
Figueiredo said that it doesn't mean that people who don't have the genetic variant should eat all the red meat.
The researcher said that people with the genetic variant allele have an even higher increased risk of colorectal cancer if they consume high levels of processed meat, but the baseline risk associated with meat is already pretty bad.
The researchers systematically searched the more than 2.7 million genetic sequences for interactions with consumption of red and processed meat. The study looked at 9,287 patients with colorectal cancer and a control group of 9,117 individuals without cancer.
The researchers speculate that the digestion of processed meat may promote an immunological or inflammatory response that may trigger tumour development.
The study was presented at the annual American Society of Human Genetics 2013 meeting.