The question: I love my steak well done, but I’ve heard medium rare is healthier. Is that true?
The answer: When it comes to nutrients – protein, iron, zinc, etc. – there's no difference between steak that is cooked medium rare or well done. The concern is that meat cooked until it's well done contains more potential carcinogens called heterocyclic amines (HCAs) than meat cooked for a shorter time.
When meat is barbecued, grilled, fried or broiled HCAs are formed when amino acids (the building blocks of protein) and creatine (a natural compound found in muscle meats) react at high temperatures. In lab animals, HCAs have been shown to cause colon tumours. In people, a heavy intake of certain HCAs has been linked with a higher risk of colon polyps. And studies that follow large groups of people over time have linked higher intakes of well-done meat to a greater risk of certain cancers.
Well-done or not, it's wise to limit your intake of red meat (e.g. beef, lamb, pork, goat). Research suggests heavy red meat eaters are at increased risk for colorectal cancer, Type 2 diabetes and coronary heart disease. Cancer experts advise eating less than 18 ounces a week.
When you do eat meat, keep your portion size small. Enjoy small amounts of red meat in stir-fries and pastas. When having steak, serve it in thin slices rather than eating the whole steak. It's also important to choose cuts of meat that are lower in fat such as sirloin, flank steak, eye of the round, beef tenderloin, lean and and extra lean ground beef, pork tenderloin, and centre cut pork chops.
If you really don't want to give up your well-done steak, there are a few things you can do to minimize the formation of HCAs when grilling. (These strategies will also help reduce the creation of HCAs in meat cooked medium and medium rare.)
- Keep meat portions small to cut down on grilling time. The less time on the grill, the less time for HCAs to form. Instead of grilling a whole steak, barbecue kebabs since they cook more quickly.
- For meats that require longer cooking times, partially pre-cook in the microwave, drain away the juices, and then finish on the barbecue. Microwaving meat for two minutes prior to grilling can result in a significant reduction in HCAs.
- Marinate meat for 10 minutes before grilling. Ingredients in a marinade such as vinegar, citrus juice, vegetable oil and spices may prevent carcinogen formation.
- Cook at a lower temperature. Turn the gas down or wait for the charcoal to become low-burning embers.
- When making burgers, add garlic and fresh chopped rosemary to the meat mixture before grilling. Both herbs have been shown to block the formation of HCAs. (In order to kill harmful bacteria that could be lurking in ground meat, beef burgers must be cooked to a safe internal temperature of 71C. Use a digital instant-red meat thermometer and check each patty.)
Leslie Beck is a registered dietitian.
