Complex sentence: Fast food is a type of mass-produced food that is prepared and served very quickly, was first popularized in the 1950s in the United States, and may be relatively lesser in nutritional value compared to other foods and dishes.
Split into simpler sentences: Fast food is a type of mass-produced food that is prepared and served very quickly. It was first popularized in the 1950s in the United States, and may be relatively lesser in nutritional value compared to other foods and dishes.