Grazing behaviour and associations with obesity, eating disorders, and health-related quality of life in the Australian population

Background
Grazing, including a compulsive subtype, represents an eating behaviour of recent interest in obesity and eating disorders (ED), however, there is little information regarding its prevalence and correlates in the general population. The current study aimed to report on the distribution of compulsive grazing (CG) and non-compulsive grazing (NCG) in the Australian population, and to assess associations with obesity, ED, and health-related functioning.

Methods
A representative sample of 3047 individuals aged ≥15 years (50.8% female) completed a cross-sectional survey in 2016 assessing grazing, quality of life, BMI, and ED symptoms. Prevalence data were obtained, and logistic regressions and multivariate analyses were conducted to examine relationships between grazing and obesity, ED, and health-related quality of life.

Results
The point prevalence of regular NCG was 38.04% (95% CI [36.33, 39.78]; n = 1159) and CG was 10.24% (95% CI [9.21, 11.37]; n = 312). Persons with regular CG had almost twice the odds of a BMI ≥ 30 than of a BMI in the "healthy" range compared to those with no grazing. CG presented stronger associations with ED features and binge-type ED diagnostic groups than NCG, with high rates found in BED-Broad and BN, although some associations with ED features were also present for NCG. Those with both ED and obesity had an 11-fold increase in the odds of engaging in CG than in no grazing, compared to those without. Mental health-related quality of life was lower in those who engaged in CG in the population, as well as in those with obesity.

Conclusions
Grazing, especially when associated with a more severe sense of loss of control, is a problematic eating behaviour in the general population, as well as in persons with high BMI, a binge-type ED, or both.