The results showed that regular consumption of red meat and processed meat increases the risk of colorectal cancer. The study also identified two genes, HAS2 and SMAD7, which can change the level of cancer risk based on the consumption level of red or processed meat.
Recently, researchers from the Keck School of Medicine at the University of Southern California published a research paper entitled "Genome-Wide Gene–Environment Interaction Analyses to Understand the Relationship between Red Meat and Processed Meat Intake and Colorectal Cancer Risk" in the journal "Cancer Epidemiology, Biomarkers & Prevention".
This large-scale study shows that regular consumption of red meat and processed meat increases the risk of colorectal cancer. People with higher intake of red meat and processed meat have a 30% and 40% increased risk of colorectal cancer, respectively.
In addition, the study also identified two genes, HAS2 and SMAD7, which can change cancer risk levels based on the consumption level of red or processed meat.
In this study, researchers analyzed data from 27 European colorectal cancer risk studies, including 29,842 colorectal cancer patients and 39,635 non-cancer patients. Participant intake of red and processed meat was collected through dietary questionnaires, and genetic data was analyzed to explore the association between red and processed meat intake and colorectal cancer.
The researchers divided the participants into four groups based on their intake of red meat (beef, pork, and lamb) and processed meat (bacon, sausage, luncheon meat, and hot dogs).
The analysis found that compared with the group with the lowest intake of red meat, the risk of colorectal cancer in the group with the highest intake of red meat increased by 30%; compared with the group with the lowest intake of processed meat, the risk of colorectal cancer in the group with the highest intake of processed meat increased by 40%.
Next, the researchers analyzed the genetic data to determine whether there was a genetic variant that could alter the risk of colorectal cancer in people who eat more red meat.
Researchers have discovered two genes, HAS2 and SMAD7, that change cancer risk levels based on red or processed meat consumption levels.
For HAS2 gene, about 66% of the population carries HAS2 gene variants, and compared with the lowest red meat intake group, the highest red meat intake group has a 38% increased risk of colorectal cancer.
For the SMAD7 gene, about 74% of the population carries two copies of the SMAD7 gene variant. For people with two copies of the variant, compared to those with the lowest intake of red meat, those with the highest intake of red meat have an 18% increased risk of developing colorectal cancer. Individuals with only one copy of the most common variant or two copies of less common variants have significantly higher cancer risks, at 35% and 46%, respectively.
Researchers said that this finding indicates that different genetic variations may lead to different risks of colorectal cancer in individuals who consume red meat, and reveals why red meat and processed meat increase the risk of colorectal cancer.
However, the researchers emphasized that the current study did not prove a causal relationship between these genetic variations.
In short, the results suggest that regular consumption of red and processed meat increases the risk of colorectal cancer. The study also identified two genes, HAS2 and SMAD7, which change cancer risk levels based on the consumption level of red or processed meat.
