Red Meat, Red Flag?

The holidays are over. The gifts have been unwrapped. The decorations are down. The holiday ham has been cooked and eaten. Now that it’s a new year, it’s time to examine whether that ham is healthy or not.

 

For years, a cornerstone of teaching in medical school, and in cardiology training programs, is that red meat is bad for health.  Red meat is animal muscle and is defined as any meat that is a dark red color before it is cooked. It has been extensively studied for many years and has consistently been associated with higher risks for heart disease, cancer, diabetes and death. However, it is important to distinguish between unprocessed and processed red meat. Unprocessed red meat is defined as beef, pork, veal or lamb. Processed red meat is preserved in some way, by smoking, salting or curing. Examples of processed red meat include sausage, delicatessen meat (such as salami or ham or pepperoni), hot dogs and bacon.  Both types have similar amounts of cholesterol and saturated fat. Processed meat has slightly more calories and less protein per serving than unprocessed meat. The big differences between the two are the salt content and the preservatives. Processed meat has four times the amount of salt and many more preservatives than unprocessed meat.  So eating a sandwich with low fat deli meat may be less healthy than eating a juicy hamburger! Based on these differences, dietary guidelines have recommended low consumption of unprocessed red meat and avoidance of processed red meat. 

 

Then the tide changed in October 2019 when the Annals of Internal Medicine published a series of papers on red meat. They also published, and aggressively promoted, guidelines based on the findings.  These guidelines were contrary to the current dogma and stated that it was fine for Americans to continue their current consumption of both processed and unprocessed red meat. They stated, “No need to reduce red or processed meat consumption for good health”. This set off a media frenzy with headlines touting “It’s OK to eat red meat!”.  What the papers actually found was that the studies were of low quality and that the researchers could not say for certain that eating red meat was bad for health. One of the problems was that studies compared a red meat diet to other unhealthy diets (which were high in refined starches, sugars and saturated fats). Compared to these other unhealthy diets, consumption of red meat did not look as bad. Critics pointed this out as well as other numerous flaws in the data. In addition, it came to light that the authors did not disclose funding from the beef industry, which could have biased the results. The Annals then published a correction. 

 

So, is it OK to eat red meat? It certainly makes sense that red met increases the risk for heart disease. Red meat is associated with increased levels of LDL cholesterol (the “bad” cholesterol). Red meat is also high in iron, which has been show to increase the risk for heart attack and heart deaths. The high salt content of processed meats increases blood pressure and damages blood vessels. Lastly, preservatives such as nitrates are associated with heart artery disease. What if red meat was compared to a diet based on plant based proteins (such as nuts, peas, beans, or lentils)?  This study was performed and published in December 2020. Researchers followed 40,000 American men for 30 years and compared red meat to plant based protein. They found that one serving of red meat per day increased the risk for heart disease by 12%. One serving per day of unprocessed red meat increased the risk to 15%. Replacing red meat with plant-based protein lowered the risk for heart disease. If red meat was substituted with fish, yogurt, cheese or eggs, the risk of heart disease decreased by 15-24%. Replacing red meat with plant proteins was even more beneficial for those over 65 years old.  The bottom line was that increasing consumption of red meat proportionally increased the risk for heart disease. However, the key to a heart healthy diet may be less about reducing red meat and more about consuming plant based foods that protect the heart. We don’t know if the goal is eating less red meat or eating more plant based protein. 

 

What can be said about red meat consumption in 2021? It seems clear that processed red meats should be avoided. If unprocessed red meat is to be eaten, then limit consumption to about once per week.  It may be best to leave the ham to a once a year tradition.