Why did the people in the Stone Age rarely have tooth decay?

Explanation

Bacteria in the mouth converts sugar into acid. Acid, which is not removed, etches the teeth and makes holes, also known as caries. The body defends teeth against caries by producing saliva. Saliva dissolves and neutralizes the bacteria's harmful acid. For the prevention of dental caries, it is important to brush with a fluoride toothpaste. Tooth decay was almost unknown to the people of the Stone Age. The diet was rich in protein, and they had no access to the sweet, sun-ripened fruit that could cause tooth decay.