Most Americans receive more than two-thirds of their protein from which source?

The correct answer is animal sources, as they are a primary provider of protein in the typical American diet. Animal proteins, such as those found in meat, poultry, fish, and eggs, are generally rich in essential amino acids, which are crucial for various bodily functions, including muscle repair and growth. This source of protein is favored in many diets due to its high biological value, meaning the body can effectively utilize it.

While plant sources do contribute a significant amount of protein, particularly among vegetarians and vegans, they typically do not account for more than two-thirds of protein consumption across the general American population. Processed foods can contain protein, but they often come with additional sugars and unhealthy fats, and usually do not make up the primary source of protein. Dairy products are also a significant source of protein, but they are generally considered part of the broader category of animal sources rather than a standalone category that provides more than two-thirds of protein intake.