Objective: To investigate whether gum chewing affects perceived levels of everyday stress among persons who (1) regularly chew gum or (2) do not chew gum on a regular basis.
Research design and methods: Two Internet-based studies were conducted. Study 1 enrolled participants who chewed gum > or =4 days per week, chewed > or =11 pieces of gum per week, and chewed gum during the previous week (frequent or heavy chewers, n = 280). Study 2 enrolled participants who had chewed gum previously but did so infrequently and had not chewed during at least the 7 days before recruitment (n = 212). Both studies used a randomized, crossover design: each participant either chewed gum or abstained from chewing for a number of sequential days, then switched to the opposite behavior for the same number of days. Stress levels were assessed by means of self-reported responses to the State-Trait Anxiety Inventory (STAI) at screening and after each test sequence.
Results: More participants (54% in study 1 [p < or = 0.10] and 57% in study 2 [p < or = 0.05]) reported that chewing gum reduced their stress level at least a little, compared with those who reported no effect on or an increase in stress. In both studies, mean STAI state scores increased significantly after the abstaining period, indicating an increase in the perceived level of stress, and decreased significantly after the gum-chewing period. Particular stress-specific emotions (e.g., not feeling relaxed, feeling tense) were reported to have significantly increased when participants abstained from chewing gum and to have decreased when they chewed. More severe levels of stress (e.g., being upset or frightened) were not affected by chewing or abstaining from chewing gum. The studies had several potential limitations, including self-reporting, a large initial recruitment, and the need for habit alteration.
Conclusions: The findings point to a relationship between decreased stress and gum chewing and suggest chewing gum may help reduce perceived levels of everyday stress.