Does Red Meat Really Cause Cancer?

The latest round of inaccurate media hype concerning health and disease is that red meat consumption causes diabetes.   But is this really true and what about the study the media is quoting?

Big outlets including the New York Times pounced on the study titled “Meat consumption and incident of type 2 diabetes: an individual-participant federated meta-analysis….”   Sounds like a done deal right?    Not so fast!

The diet information reviewed was all self-reported – huge red flag on this!   Self-reported food intake is notoriously very inaccurate.    In addition, the study has a common flaw – confusing correlation with causation.    This is a frequent blind spot in many studies.

The idea that red meat consumption causes diabetes is just one of many possible explanations for the association the study found between red meat consumption and diabetes.

There are literally hundreds of other variables that could account for the increase in diabetes in the study.   For example, socioeconomic factors are known to influence health outcomes.  For instance, high intake of processed meats is often associated with lower income due to lower costs (think hot dogs, cured meats).   In addition, lower income people tend to have lower access to quality healthcare which could detect pre-diabetes and prevent progression to full diabetes.

Lower income groups also tend to engage in lower levels of known healthy behaviors like exercise, not smoking and not drinking alcohol.  In addition, since many people believe that meat is unhealthy, those most focused on being health often avoid meat – yet they engage in many other healthy behaviors.

Studies attempt to correct for these mitigating factors, but it is impossible to do this completely or account for every factor which might play a role.  Another significant factor that runs contrary to the study conclusions is that when we adjust for BMI (body mass index) the increased risk of diabetes is cut in half.     This leaves a 10% increased risk for every 100 grams per day of unprocessed meat, 15% for every 50 grams of processed meat, and 8% for every 100 grams per day of poultry.   Given that no study can account for all confounding variables, these numbers are very small and cause plenty of doubt about any causal relationship between red meat and diabetes.

In addition, when you dig into subpopulations in the study many showed no significant association between any form of meat and diabetes including Eastern Mediterranean or Southeast Asian populations.     More significantly none of the regions in Europe showed significant positive association between poultry intake and diabetes.

So long story short – this study ads no value in terms of providing evidence that red meat consumptions causes diabetes.     At the same time this is not evidence that people should increase red meat consumption – rather that in and of itself people should not fear that consuming red meat will cause them to have diabetes.

As always the best advice is to regularly exercise, avoid being overweight, avoid smoking, moderate or eliminate alcohol intake, and focus on a whole food diet with minimal amounts of processed foods!