Red meat has almost certainly featured in the human diet for a large portion of our evolution, and its primal nature is one reason why I believe this food can assume some place within a ‘healthy’ diet of today. However, I am well aware that red meat is usually viewed as distinctly unhealthy fare, and warnings regarding the perils associated with its consumption abound. One common recurring theme concerns red meat’s supposed ability to cause cancer in the colon. Earlier this year, for instance, the British Medical Journal (BMJ) reported on study that it claimed ‘confirmed’ the link between red meat and colon cancer. Such reports give the impression that those who eat red meat are like lambs to the slaughter.
I thought I might subject the study cited in the BMJ to closer scrutiny, to see if the eating of red meat does indeed sound alarm bells for the bowel. The study, published in the Journal of the American Medical Association, assessed the relationship between diet and cancers of the colon and rectum (the last part of the colon) in some 150,000 individuals. Consumption of processed meat (such as bacon, sausage, hot dogs, ham and salami) and red meat was assessed in 1982 and then in 1992/1993, and study participants were followed until 2001.
This study found that high red meat consumption as assessed in just 1992/1993 (shorter term) or in both 1982 and 1992/1993 (longer term) was not associated with an increased risk of colon cancer. High consumption of red meat in the shorter term was, however, associated with an statistically significant increased risk of cancer of the rectum. Curiously, though, this effect seemed to wane in time, with longer term consumption being only ‘marginally associated’ with rectal cancer risk. This rather unconvincing link was not in any way strengthened by fact that higher intakes of processed meat did not seem to increase rectal cancer risk. High processed meat consumption in the longer term was, however, associated with a somewhat increased risk of colon cancer.
It is perhaps worthwhile viewing these less-than-conclusive findings in the context of the wider evidence: a review of the available literature in this area published in the European Journal of Clinical Nutrition found that of 44 relevant studies, most (31) found no apparent association between red meat intake and colon cancer risk. Despite the assertion of the BMJ, it is clear that the link between red meat and colon cancer is anything but ‘confirmed’.
Those wishing to eat red meat might do well to avoid processed meats that are more likely to be laced with carcinogenic chemicals. Some evidence for this rationale comes from a study published in the International Journal of Cancer in 2002 which found that, weight for weight, processed meat has significantly more cancer-causing potential in the colon than red meat. Further avoidance of potentially disease-making substances may be had by opting for organic meat wherever possible. While my appetite for occasional quality red meat remains undiminished, I suggest de-emphasising processed and non-organic meats in the diet is a good strategy for those wishing to save their bacon.