With the nation experiencing its first case of mad cow disease (search), the grocery store's meat aisle has become a place where consumers worry about more than the prices.
Several food safety (search) experts offer this advice to consumers worried about contracting the human form of the disease: Don't eat cow brains. And if you are especially concerned, avoid ground beef if you don't know what part of the cow it came from.
But the nutritionists and public health experts also urge consumers not to panic, stressing that only one case in a cow has been discovered and that the human form of the illness is very rare.
"This may be nothing. It may be something," said Marion Nestle, author of the book "Food Safety" and a professor of food nutrition studies at New York University. "The risk is very low. On a statistical basis, it's nothing. But if it's you (who develops the disease), it makes a huge difference."
Mad cow disease is officially known as bovine spongiform encephalopathy (search), or BSE. Humans can contract a fatal variant of the disease by eating infected beef products. A total of 153 people worldwide have developed it, according to the federal Centers for Disease Control and Prevention.
The discovery of mad cow in the United States has some consumers questioning whether they should change their diet:
Q. Should I stop eating all beef?
A. No. In almost two decades of research, scientists have never found the misshapen protein that eats holes in a cow's brain — called a prion — in the muscle that makes up cuts of meat. Instead, the protein resides in nerve tissue, specifically the brain and spinal cord. along with the lower part of the small intestine, eyes and tonsil, said Dean Cliver, a food safety professor at the University of California at Davis who has served on several government panels examining BSE.
Q. So why is there any concern?
A. Some people consider cow brains a delicacy. Also, the spinal cord and assorted nerve bundles are not always removed from cattle before processing begins at meatpacking plants, said William Hueston, head of the Center for Animal Health and Food Safety at the University of Minnesota. Machines that are designed to strip as much flesh off the bone as possible can accidentally include some of that central nervous system material, Hueston said.
Q. How do I avoid getting beef that could contain infected neural material?
Experts say "muscle" cuts like roasts, chops and steaks are fine. The "t" in a T-bone steak comes from the area where the vertebrae in the backbone meet the rib. Sometimes that meeting point still contains a piece of the spinal cord, which consumers should avoid eating, Cliver said.
Q. What should I do about ground beef?
If consumers are worried about neural tissue being contained in ground beef, they can buy a labeled cut of meat, such as chuck or round, and have the butcher grind it for them, said both Nestle and Hueston.
But Ruth Kava, director of nutrition at the American Council on Science and Health, said she sees no reason to avoid ground beef. The risk of contacting the human form of the disease needs to be put into perspective, she said. "It's more important to wash your hands and not kiss someone with the flu," she said.
Q. Should I avoid processed meats, like hot dogs, luncheon meats and pizza toppings?
You want to look for products made from cow muscle but, as in the case of ground beef, quality varies. "You get what you pay for," Hueston said. Processed products are made from several sources of meat, and some tests have detected tissue from the central nervous system in samples of beef products. Hueston recommends consumers contact the food company or go to its Web site to find out exactly what raw products go into its processed meats.
Q. Any concerns about milk products? Or less popular parts of the cow such as oxtails, tongue, liver and beef cheeks?
Prions have never been found in dairy products, said Christine Bruhn, director of the Center for Consumer Research at the University of California at Davis. Prions also have not been found in organs, like livers. Beef cheeks and tongue are muscle and therefore fine, but oxtails could contain neural tissue, Kava said.
Q. Does anyone think this is overblown?
Yes. Several food safety experts said they wish the attention being spent on mad cow disease would be used to persuade Americans to take steps that could save many lives each year — like using thermometers to make sure meat is cooked properly and employing proper hygienic procedures in the kitchen to avoid the transmission of bacteria such as E. coli and salmonella.
"More people die from pathogenic bacteria in this country every year than have fallen prey to (the human form of mad cow disease) in the United Kingdom," Bruhn said.