Normal weight: body mass index = 18-25.
Overweight: body mass index = 25-30.
Mild obesity: body mass index >; 30
Moderate obesity: body mass index >; 35
Severe obesity: body mass index >; 40
Extended data:
Professor stiles, an American gerontologist, found that among people over 70 years old in California, those who exceed the standard weight 10% ~ 20% have the lowest mortality rate. When the weight is too low or too high to 30%, it is easy to cause diseases and affect life expectancy.
The reason why obese people live longer is that the subcutaneous fat layer of obese people is thicker, and their cold resistance and disease resistance are stronger than those of ordinary people, and they can withstand the "torture" of diseases. However, thin people have relatively weak resistance and poor adaptability to the environment, especially acute infectious diseases such as influenza, upper respiratory tract infection and pneumonia, so they are sick and short-lived.
Medical research also found that if women lose weight significantly from the age of 50, they are prone to fractures, especially hip fractures. In addition, the incidence of visceral ptosis in thin people is very high, and the most obvious is gastroptosis.
Therefore, when people get old, they should not be too fat, but they should not be too thin, and it is better to be a little fat. Of course, exercise and mental health are also important.
Baidu encyclopedia-weight