The aim of the study was to establish the importance of an additional measurement of subcutaneous adipose tissue thickness (SAT) on a predetermined position on the waistline, and its relation to waist measurements as an improvement of metabolic prediction in equally obese subjects. One hundred and forty two consecutive patients were enrolled in the study: stratified by weight as normal (body mass index - BMI 20–25 kg/m2), overweight (BMI 25–30 kg/m2) and obese (BMI >30 kg/m2); and by fasting glucose level as normoglycemic, impaired fasting glucose (IFG), or with type 2 diabetes mellitus (T2DM). SAT was measured in relaxed expiration, 3 cm left of the umbilicus, with ultrasound. Fasting blood samples for glucose, insulin and HbAlc were taken. Waist circumference was slightly higher in the IFG (112.8 cm) and normoglycemic groups (115.62 cm), compared to T2DM (108.15 cm). The T2DM group had a lower average SAT (2.7 cm) than both the IFG group (3.4 cm, p<0.01) and the normoglycemic group (4.2cm, p=0.001). The homeostatic model of assessment for insulin resistance (HOMA IR) was the lowest in normoglycemic and the highest in IFG group. Waistline radius to SAT ratio provides better insight into the deterioration of glucose metabolism than standard anthropometric markers of abdominal obesity in equally obese patients.