What science still hasn’t told us about red meat
The Takeaway First
Despite the huge conversation that health professionals and consumers alike are having about the effects of consuming red meat on human health, scientific research hasn’t quite settled the score. A new paper (Klurfeld, 2015) published this past May highlights the many limitations of the studies we have done. So what do we have left…?
- David Klurfeld highlights some flaws in the current literature surrounding red meat. In order to know for sure whether red meat causes diseases long-term, for example, we would need a longitudinal study (where subjects are tracked for several decades) with an extremely large sample size. Not only have we not done this, but we can’t; it’s too expensive.
- Besides, says Klurfeld, supposing we had the money, scientists can’t feed red meat to humans on the premise that it might cause them to become diseased. It’s unethical.
- The nature of observational studies and the immense amount of data that researchers collect enables such studies to find (potentially) thousands of statistically significant correlations, many of which may simply be false positives.
- Some influential studies that have found significant associations between meat consumption and colorectal cancer are clouded by confounding variables such as daily caloric intake and smoking.
- While known toxins such as tobacco and alcohol increase risks of lung cancer and liver cirrhosis ten- to thirty-fold, eating meat does not increase the risk of any disease by more than 50 percent.
My Take on Meat
It seems from this paper that we should be cautious when we say that eating or not eating red meat poses a danger to our health. Not only are the data limited and easy to skew, but the data on the increased risk of disease forces us to ask, “How much of a difference does this really make?”
In my opinion, we should not be worried about meat so much as wheat and simple carbs like pasta, bread, cookies, and flour. Meat should only worry us when it’s in excess or excessively cooked, as one study has shown that charred meats contain carcinogens (Zheng et al. 2009).
Of course, I have long believed, and still believe, that individual differences can make or break a diet for anyone. This is why I design an individualized anti-cancer lifestyle plan for each of my patients. For patients whose baseline risk for disease is elevated due to heredity or past behavior, I adjust their plans accordingly.
What You Should Do
When our modern methods fail to provide satisfying answers to these questions, we can be sure of one thing: uncertainty about how much does not equal a license to let ourselves go. In other words, it would be detrimental to your health if you used uncertainty as an excuse for irresolution and made a habit of saying, “Well, since we don’t really know, I guess I’ll just stick to my usual breakfast of three fried eggs and half a pig.”
While we may have reasons to be skeptical about the “statistically significant correlations” that bring smiles to every researcher’s face, we cannot afford to be wishy-washy about our commitment to a balanced diet of whole foods. Balance, unlike meat, has well-known effects. Moderation in all things—that’s the key.
Klurfeld, D. M. Research gaps in evaluating the relationship of meat and health. Meat Science(0). doi: http://dx.doi.org/10.1016/j.meatsci.2015.05.022
Zheng, W., & Lee, S.-A. (2009). Well-done Meat Intake, Heterocyclic Amine Exposure, and Cancer Risk. Nutrition and Cancer, 61(4), 437–446. doi:10.1080/01635580802710741