Waist–hip ratio
WHR is used as a measurement of obesity, which in turn is a possible indicator of other more serious health conditions. The WHO states that abdominal obesity is defined as a waist-hip ratio above 0.90 for males and above 0.85 for females, or a body mass index (BMI) above 30.0. The National Institute of Diabetes, Digestive and Kidney Diseases (NIDDK) states that women with waist-hip ratios of more than 0.8, and men with more than 1.0, are at increased health risk because of their fat distribution.
Female body shape
A low waist–hip ratio has also often been regarded as an indicator of attractiveness of a woman, but recent research suggests that attractiveness is more correlated to body mass index than waist–hip ratio, contrary to previous belief. Historically, according to Devendra Singh, there was a trend for slightly overweight women in the 17th and 18th centuries, as typified by the paintings of Rubens, but that in general there has been a preference for a slimmer waist in Western culture. He notes that "The finding that the writers describe a small waist as beautiful suggests instead that this body part – a known marker of health and fertility – is a core feature of feminine beauty that transcends ethnic differences and cultures."