the largest component of the body is water, accounting for about 50% - 60% of body weight, followed by fat. others are proteins and sugars contained in muscles, and inorganic substances contained in bones.

body fat percentage refers to the ratio of body fat to body weight.

the body fat rate of boys is about 17-23%, and the body fat rate of girls is about 20-27%. for boys under 30 years old, 14~20%. for boys over 30 years old, 17~23%. for girls under 30 years old, 17~24%. for girls over 30 years old, 20~ 27%, the average bmi value of boys is about 20~25% and the bmi value of girls is about 19~24%