People may choose to stop eating meat for a variety of different reasons, but the two biggest reasons are diets and lifestyles. Some people may choose to go without meat because it's high in calories and fat, while others choose to be vegetarians because the don't agree with the slaughtering of animals. Regardless of why people choose meat free diets, they should still be concerned with getting protein into their diets. Protein helps to build muscle and muscle keeps bones strong, but most protein comes from meat.