pathogenesis of obesity? How is it defined for clinical purposes?
Both genetic and environmental factors play a role in the development of obesity. In general, excess energy intake relative to expenditure results in the accumulation of body fat over time.
The regulation of adipose tissue is complex and involves the central and sympathetic nervous systems, hormones (e.g., ghrelin, leptin, and cortisol), and even the gut microbiome (increased concentrations of Firmicutes species).
The clinical definition of obesity is based on body mass index (BMI), calculated by the formula:BMI=bodyweight(inkg)height(inmeters)2BMI=bodyweightinkgheightinmeters2
BMI classifications are as follows:
- Normal: 18.5 to 24.9 kg/m 2
- Overweight: 25 to 29.9 kg/m 2
- Obese: 30 to 39.9 kg/m 2
- Morbid Obesity: >40 kg/m 2