Prevalence of chew and spit and its relation to other features of disordered eating in a community sample

Background: Until recently, research into Chew and Spit (CHSP) behavior has predominantly focused on clinical samples, and little is known of its prevalence in the community. The current study aimed to bridge this gap by exploring CHSP features in a representative sample of the general population. We hypothesized that the point-prevalence of CHSP would be less than 1%; concurrent with other eating disorder symptomology, and associated with poorer health related quality of life (HRQoL).

Methodology: Using the 2016, respondent-based, South Australian Health Omnibus Survey (HOS), data were collected on 3047 participants aged ≥15 years old. HRQoL was assessed with the Short-Form health-questionnaire-v1 (SF-12).

Results: CHSP point prevalence was 0.4% (95% CI .23 to .69%; n = 13), and was more prevalent in people with compensatory disordered eating behaviors. The median age of those with CHSP was 39, and both mental and physical HRQoL were reduced compared with the general population (Mdn: MHQoL = 49; HRQoL = 50), with MHQoL being significantly lower in those with symptoms of a clinically diagnosable ED and concurrently engaged in CHSP (z = -2.33, p = .020).

Conclusions: Due to the low prevalence of CHSP, the reliability of inferential statistics may increase the chance of Type II errors, therefore, future studies should use larger samples. Although CHSP is not "common" in a wider community sample, its prevalence appears to be similar to other ED associated symptoms.