What's really in that hot dog?

Each year between Memorial Day and Labor Day, Americans consume 7 billion hot dogs (that's 818 every second!), according to the National Hot Dog and Sausage Council.

But before you top these summer standbys with ketchup and relish and dig in, there are a few things you need to know.

"A hot dog is a processed meat that is generally high in unhealthy saturated fat and sodium and contains nitrites, which may be cancer causing," says Dawn Jackson Blatner, RD.

So how do you pick out the healthiest hot dog?

Prevention magazine walks you through the nutrition label so you know which harmful or suspicious ingredients (mechanically separated turkey, anyone?) to look out for — and how to pick a more nutritious dog.

Beef and Pork: Both are high in protein — and in unhealthy saturated fat and cholesterol; the meat could come from pig and cow skeletal muscle and by-products.

Mechanically Separated Turkey: A pastelike substance produced when tissue is removed from bones through a high-pressure sieve. This product is versatile and cheap—and not just for turkey dogs.

Sodium Nitrate: Helps preserve the red tint of cured meat. Studies have shown that consuming sodium nitrite may increase cancer risk and trigger migraines.

Corn Syrup: A combo of cornstarch and acids, corn syrup is used as a thickener and sweetener. It contains no nutrients but does add extra calories.

Extractives of Paprika: As a spice, paprika is a good source of fiber and vitamins A and E. However, the extractive form doesn't offer much aside from color.

Better Buy: Applegate Farms Organic Beef Hot Dogs made with USDA-certified organic beef and without nitrites and corn syrup, these dogs are lower in saturated fat, calories, and sodium than typical supermarket or ballpark fare.

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