Category BMI (kg/m2) Underweight 2: weight , height . He presents with stretch marks and enlarged breasts.<unk>  is typically defined as a substantial accumulation of body fat that could impact health. Medical organizations tend to classify people as<unk> ese based on body mass index (BMI) – a ratio of a person's weight in kilograms to the square of their height in meters. For adults, the World Health Organization (WHO) defines overweight as a BMI 25 or higher, and<unk> ese as a BMI 30 or higher. For children,<unk>  measures take age into consideration along with height and weight. For children aged 5–19, the WHO defines<unk>  as a BMI two standard deviations above the median for their age (a BMI around 18 for a five-year old; around 30 for a 19-year old). For children under five, the WHO defines<unk>  as a weight three standard deviations above the median for their height. The U.S. Centers for Disease Control and Prevention (CDC) further subdivides<unk>  based on BMI, with a BMI 30 to 35 called class 1<unk> ; 35 to 40, class 2<unk> ; and 40+, class 3<unk> . It further evaluated in terms of fat distribution via the waist–hip ratio and total cardiovascular risk factors. BMI is closely related to both percentage body fat and total body fat. In children, a healthy weight varies with age and sex.<unk>  in children and adolescents is defined not as an absolute number but in relation to a historical normal group, such that<unk>  is a BMI greater than the 95th percentile. The reference data on which these percentiles were based date from 1963 to 1994, and thus have not been affected by the recent increases in weight. Some modifications to the WHO definitions have been made by particular organizations. The surgical literature breaks down class II and III or only class III<unk>  into further categories whose exact values are still disputed. * Any BMI ≥ 35 or 40 kg/m2 is severe<unk> . * A BMI of ≥ 35 kg/m2 and experiencing<unk> -related health conditions or ≥ 40 or 45 kg/m2 is morbid<unk> . * A BMI of ≥ 45 or 50 kg/m2 is super<unk> . As Asian populations develop negative health consequences at a lower BMI than Caucasians, some nations have redefined<unk> ; Japan has defined<unk>  as any BMI greater than 25 kg/m2 while China uses a BMI of greater than 28 kg/m2.
Obesity
Heart failure
Body mass index
Metabolic syndrome
Abdominal obesity
Family history 
Dry sex
Smoking