Normal Weight Central Obesity and its Impact on Type 2 Diabetes Mellitus

The aim of this review is to provide an updated commentary on the current literature examining the impact of normal weight obesity (NWO) and normal weight central obesity (NWCO) on type 2 diabetes mellitus in adults.

Total 14 studies were included, comprising 9 cross-sectional and 5 cohort studies with 334,438 subjects. The quality of evidence was mixed. The pooled prevalence of NWO was 16.1% (95% CI: 12.7—19.4) and NWCO was 21.1% (95% CI: 12.2—30.1). The prevalence of NWO and NWCO higher in females and non-Asians. This review also showed that type 2 diabetes was significantly associated with NWO and NWCO (pooled OR: 1.82 [1.62, 2.04], p < 0.01, I2 = 64%). Subgroup analyses revealed consistent relationships between type 2 diabetes and NWO/NWCO across sex, region and definition approach.

There was a relative high prevalence of NWO and NWCO, particularly in females and non-Asian populations. There was a consistent association of NWO/NWCO with type 2 diabetes. Implications for future research to guide intervention optimization in clinical practice and public health promotion are provided.