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.
The standard weight is our height minus 105. For example, if our height is 1.65 meters, our weight should be 60 kilograms. Even if the number fluctuates up and down, it is still a normal weight.