BMI and abdominal obesity
• Height and weight are used to calculate BMI, an indicator of obesity• BMI=weight (kg)/ height (m)2
• Waist circumference is an indicator of abdominal obesity
Classification of BMI
Classification BMI
Underweight < 18.5
Normal weight 18.5 – 24.99
Overweight ≥ 25
Obese ≥ 30
Waist circumference, cut-points for abdominal obesity:
> 102 cm for men> 88 cm for women
Fundamental causes for obesity and overweight
• An energy imbalance between calories consumed and calories expended
• Sedentary lifestyle• Lack of physical activity, irregular sleep patterns
• Unhealthy diet and eating habits• E.g. increased intake of fat, salt and sugars• Irregular eating patterns
• Health behavior changes due to environmental and societal changes
Other causes for obesity and overweight • Some medications
• E.g. antidepressants, anti-seizure medications, steroids and beta blockers
• Some medical problems• E.g. hypothyreosis, polycystic ovary syndrome, etc.
• Genetic factors
Reporting bias• People may not know their current height and
weight• Self-reported height is usually overestimated by
1.5 cm• Self-reported weight is usually underestimated by
1-1.5 kg• Obese people underestimate their weight more
than people with normal weight
Gender differences • Women underestimate their weight more than
men• Men overestimate their height more than
women
Top Related