Prolonged Chewing at Lunch Decreases Later Snack Intake

Prolonged chewing of food can reduce meal intake. However, whether prolonged chewing influences intake at a subsequent eating occasion is unknown. We hypothesised that chewing each mouthful for 30s would reduce afternoon snack intake more than (a) an habitual chewing control condition, and (b) an habitual chewing condition with a pauses in between each mouthful to equate the meal durations. We further hypothesised that this effect may be related to effects of prolonged chewing on lunch memory. Forty three participants ate a fixed lunch of sandwiches in the laboratory. They were randomly allocated to one of the three experimental groups according to a between-subjects design. Appetite, mood and lunch enjoyment ratings were taken before and after lunch and before snacking. Snack intake of candies at a taste test 2h after lunch was measured as well as rated vividness of lunch memory. Participants in the prolonged chewing group ate significantly fewer candies than participants in the habitual chewing group. Snack intake by the pauses group did not differ from either the prolonged or habitual chewing groups. Participants in the prolonged chewing group were less happy and enjoyed their lunch significantly less than participants in other conditions. Appetite ratings were not different across groups. Rated vividness of lunch memory was negatively correlated with intake but there was no correlation with rated lunch enjoyment. Prolonged chewing of a meal can reduce later snack intake and further investigation of this technique for appetite control is warranted.