Chewing chewing, the food (now called a bolus) is swallowed. It enters the esophagus and via peristalsis continues on to the stomach, where the next step of digestion occurs. Premastication is sometimes performed by human parents for infants who are unable to do so for themselves. The food is masticated in the mouth of the parent into a bolus and then transferred to the infant for consumption. (Some other animals also premasticate.) Cattle and some other animals, called ruminants, chew food more than once to extract more nutrients. After the first round of chewing, this food is called cud. Chewing is
Chewing sensory perception of the food being eaten, controlling when the food is swallowed. Avoiding chewing, by choice or due to medical reasons as tooth loss, is known as a soft diet. Such a diet may lead to inadequate nutrition due to a reduction in fruit and vegetable intake. Chewing also stimulates the hippocampus and is necessary to maintain its normal function. Chewing is largely an adaptation for mammalian herbivory. Carnivores generally chew very little or swallow their food whole or in chunks. This act of gulping food (or medicine pills) without chewing has inspired the English idiom "wolfing it down".