When I have asked clients what makes up a heart-healthy diet, I have often heard statements about eating less red meat and replacing it with fish or chicken and lots of vegetables.
When I ask why they single out red meat, the reason often is that red meat is high in cholesterol and/or saturated fat, or that red meat is simply not healthy to eat. Is this true or just another diet myth?
Recent studies suggest that indeed red meat may be bad for one’s heart, but not because of the fat or cholesterol. The new bad boy on the block is carnitine.
L-carnitine is a substance found in red meat that is eventually metabolized or broken down by bacteria in the intestinal tract. During the digestion of L-carnitine, other compounds are formed that are thought to increase the risk of cholesterol build-up in the arteries.
The research into carnitine comes from a group led by Dr. Stanley Hazen and Robert Koeth of the Lerner Research Institute and the Miller Family Heart and Vascular Institute at Cleveland Clinic. Their work was published first in Nature Medicine and most recently in Cell Metabolism
Although the research may seem to cast a disparaging light on carnitine, this compound has important roles in the body. For one, carnitine takes certain fats to the part of the cell called the mitochondria, the little power plates in our cells that process nutrients for energy.
Another job of carnitine is to transport toxic substances out of the mitochondria. Mother Nature was good to us in that we make plenty of carnitine in our kidneys and liver without needing it from food.
The research on red meat and carnitine that suggests an association with heart problems is interesting. According to Dr. Mozaffarian at Brigham and Women’s Hospital, though, the association between red unprocessed meat and heart disease is weak. However, salty processed meats, such as cold cuts, sausage, and bacon, show a greater degree of harm than the unprocessed red meats. And this is not a new finding.
So what is a meat-lover to do when even the experts are not sure of these new findings?
If you are concerned about heart disease, limit portion size to 3 ounces of meat per person and include more fowl and fish in your weekly meal plans. Increase the number of servings of vegetables to decrease overall fat and increase fiber, two other ways to protect your heart and overall health. Low-fat and fat-free diary along with legumes and other vegetarian options can help provide protein as your meat consumption decreases.