Skipping breakfast and risk of type 2 diabetes: A systematic review and meta-analysis of prospective studies

Abstract

Introduction Epidemiological studies have indicated that breakfast skipping is associated with increased risk of type 2 diabetes. Findings are not conclusive and the shape of the dose-response association and the potential impact of adiposity has not been investigated in systematic reviews and meta-analysis. To summarize evidence on this topic, a systematic review and meta-analysis was conducted. Methods PubMed and Web of Science were searched up to August 2017 by two researchers. Prospective cohort studies on breakfast skipping and type 2 diabetes were included. Summary relative risks (RRs) and 95% confidence intervals (95% CIs) were estimated using a random effects model. Meta-analysis on ever vs. never skipping breakfast (without and with adjustment for body mass index), as well as linear and nonlinear dose-response relations between breakfast skipping and risk of type 2 diabetes were conducted. Results We identified six studies including 4935 cases with type 2 diabetes among 96,175 participants. The summary RR (95% CI) for type 2 diabetes comparing ever versus never breakfast skipping was 1.33 (95% CI: 1.22–1.46, n = 6 studies), and 1.22 (95% CI: 1.12–1.34, n = 4 studies) after adjustment for body mass index. The summary RR (95% CI) of breakfast skipping per one day per week was 1.06 (95% CI: 1.03–1.09, n = 3 studies). The nonlinear dose-response meta-analysis showed that the curve was steeper at the beginning and highest risk was observed for 4–5 days of breakfast skipping per week [summary RR: 95% CI: 1.53 (1.26–1.86)]; with no further increase afterwards (P for nonlinearity = 0.08). Conclusions This meta-analysis provides evidence that breakfast skipping is associated with an increased risk of type 2 diabetes, and the association were still significant after adjustment for adiposity. Healthy daily breakfast eating may help lower risk of type 2 diabetes.