Standard weight (female) = (height cm- 100)x0.9 (kg) -2.5 (kg)
Normal weight: standard weight+-(how much) 10%.
Overweight: over standard weight 10% and under standard weight by 20%.
Mild obesity: 20% above standard weight and 30% below standard weight.
Moderate obesity: 30% above standard weight and 50% below standard weight.
Severe obesity: more than 50% of standard weight.