Taco Bell, with 5,600 restaurants, said in a statement it is "proud of the quality of our beef and identify all the seasoning and spice ingredients on our website."
But a lawsuit filed in a California court claims Taco Bell menu items aren't what they seem. The suit alleges products, such as beef tacos and burritos, advertised with seasoned beef actually contain a filling made up of mostly "non-meat substances," including soybean oil and silicon dioxide, that wouldn't measure up to United States Department of Agriculture standards for calling something beef.
Dee Miles, an attorney involved in the class-action suit, told CBS News, "According to the tests that we have taken, the taco meat filling is again about 35 percent meat."
Nutritionists, Don Teague reported on "The Early Show," have always been skeptical of fast food.
Registered nutritionist Tanya Zuckerbort said, "If you're thinking that you're getting beef, but you're actually getting something else, it could be putting your health at risk."