When you sink your teeth into a juicy, tasty burger, the last thing on your mind is that you could be taking your life in your hands. But as it turns out, you may be playing Russian roulette with your health every time you take a bite.

That’s because the ground beef that makes up food favorites like hamburgers and meatballs can contain potentially deadly bacteria, such as E.coli (particularly Escherichia coli O157:H7), as well as Salmonella, Campylobacter jejuni, Listeria monocytogenes and Staphylococcus aureus—all of which can cause serious illness, especially if you’re very young, very old or have a compromised immune system.

An E-coli infection can bring on abdominal cramping, diarrhea (or bloody diarrhea), kidney failure and even death, while the Salmonella health risks include diarrhea, vomiting, fever and nausea, according to nutritionist Keri Glassman, author of “The O2 Diet: The Cutting Edge Antioxidant-Based Program That Will Make You Healthy, Thin, and Beautiful.” Not exactly what you’d call “good times.”

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What’s more, “you can’t eye food-borne illness—you can’t see it or smell it,” says Dawn Undurraga, a nutritionist with the nonprofit Environmental Working Group. “And it only takes a little bit of E.coli to make people very sick.”But the fact that eating ground beef can be a gamble shouldn’t come as a surprise. The news frequently reports recalls of ground beef tainted with E.coli.

Just last month, Tyson Fresh Meats recalled more than 131,000 pounds of ground beef after a family in Ohio got sick from eating the manufacturer’s beef, which tested positive for E. coli O157:H7.

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All four children in the family fell ill, including a nine-year-old with severe diarrhea who was hospitalized for 10 days.

What Hamburgers Are Really Made Of

So why is ground beef particularly problematic? Part of the reason is because of where it comes from. What few people realize is that hamburgers are basically made from meat mash-ups.

“Ground beef is not the meat of a single cow,” explains Caroline Smith DeWaal, director of food safety at the Center for Science in the Public Interest in Washington, D.C. “Many consumers have the mistaken impression that it comes from a single animal. The way meat is produced today, a single burger can contain meat from 12 to 20 animals.”

And sometimes the ground beef comes from animals in different parts of the world in order to get the right mix of lean and fat meat. “What that means is the risks that we’re exposed to are not just risks from a single animal and what the animal itself was exposed to, but rather different hazards coming from different areas of the country or different parts of the world,” continues DeWaal.

Adds Glassman, “The parts of the cow used for low-grade meats are the areas that are most likely to be contaminated with feces. The meat companies do not test for E-coli O157:

H7 when the ingredients are separate; they only check for E-coli when the meat is ground all together.”

So by comparison, opting for steak may be the healthier choice, at least in regards to bacteria exposure (what red meat does to your heart is another story). According to the USDA, when beef is ground, more of the meat is exposed to harmful bacteria. “While a steak might be cooked thoroughly or seared on the outside where pathogens would be, with ground beef the outside and inside of the meat have been mixed up,” says DeWaal. “If you have E.coli on the outside, it can get on the inside.”

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How to Eat Meat Safely

The good news is that the USDA recently announced that it will be stepping up its efforts in the battle against beef-borne bacteria. Starting in March 2012, the department will expand its E. coli testing program for raw beef beyond the dangerous O157:

H7 strain to search for six other potentially deadly strains of E. coli.

In the meantime, if you choose to chow down on a burger, there are steps you can take to protect yourself. When it comes to ground beef, the two biggest threats to your health are cross-contamination and undercooking. So cleanliness and cooking meat thoroughly are key to protecting your health.

“We urge consumers to be very cautious in handling any meat products,” says DeWaal. “Bacteria can be spread around the kitchen while handling raw meat. Anything the raw beef touches whether a plate, chopping board or utensils need to be scrubbed with soapy water or put in the dishwasher before it’s used on any food product.”

Another way to guard against dangerous bacteria is to make sure you cook ground beef thoroughly by using an instant read meat thermometer. You can pick one up at Brookstone or at supermarkets, which sell instant disposable thermometers near where meats are sold. “Check your meat in a couple of difference places to make sure it’s thoroughly cooked,” suggests DeWaal.

But is it risky to order meatballs or a burger when you’re at a restaurant? “It depends on the restaurant,” says DeWaal. “A number of fast food chains have recognized the real risk to their brands and have developed foolproof systems for cooking hamburgers. Since the Jack in the Box outbreak”—in 1993, four children died and many became ill after eating E.coli infected beef at the fast food chain—“fast food restaurants have put a lot of safety into their practices, but not every restaurant follows those practices.”

Your safest bet? Make your meatballs and hamburgers at home. Or if you’re ordering take-out or eating a restaurant, have your meat cooked “well done.”
Here are more surefire ways to safeguard your health when eating meat:

Heat things up. Cook the meat at a high enough temperature—160 degrees—to kill all pathogens. “That’s the only real way to know you’ve killed E.coli,” says Undurraga.

Divide and conquer. Separate the meat from other foods in the fridge and store it on the bottom shelf to prevent cross-contamination, suggests Glassman. Also, use different cutting boards and utensils for meats versus vegetables.

Stay in the clear. When cooking the ground beef, it should no longer be pink. “The juices should be clear,” says Glassman.

Give meat the big chill. Make sure you’re storing meat at the proper temperature—40 degrees or below. “E.coli can grow if the temperature is higher than 40 degrees—that’s the temperature danger zone,” says Undurraga. According to the USDA, once E.coli gets in food, the bacteria can multiply very slowly at temperatures as low as 44 degrees.

Defrost carefully. Always thaw meat by moving it from the freezer to the fridge or by using the defrost setting on your microwave. “Don’t leave it out on the counter to thaw,” says Undurraga.

Toss meat that’s past its prime. According to FoodSafety.gov, you should refrigerate raw ground meats, all poultry and seafood for one to two days; refrigerated raw roasts, steaks and chops (beef, veal, lamb, and pork) can last three to five days; and you can keep cooked meat, poultry and seafood in the fridge three to four days.

Of course the best way to protect yourself is to give it up altogether!

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