(1) The first common equation to calculate normal body weight is:
| Normal body weight = | body height (cm) – 105 to 110 = body weight (kg) |
| Standard body weight = | normal body weight + 10% to 20% |
If it is 10% above the normal body weight, it means overweight.
If it is 20% above the normal body weight, it is obesity.
- The Second common equation to calculate normal body weight is to multiply the square of body height (m) with 22
If body height is 160 cm, then it is = 22 * 1.6 * 1.6 = 56.32 Kg.
- Constitution exponent
(international standard proportion of body height to body weight, namely BMI “Body Mass Index”)
Today, many people have noticed that numerical value of body weight should not be the only standard for weight reduction, and then, they give out normal constitution exponent that which can more easily indicate one’s constitution:
| Constitution exponent = | body weight (kg) ÷ body height (m) |
The normal standard value is between 17-25.
(World Health Organization standard is at least 18.5)
- If the exponent is below the standard, it is malnutrition.
- If the exponent is between 25-30, it is overweight.
- If it is over 30, it is obesity.
Some Japanese scholars surveyed that the standard constitution exponent is :
- 23 in Asian-Pacific area,
- 27 in Japan and
- 30 in Euro-American countries.
| If a man weights 68 kg, body height is 1.64 m, then the exponent is 68 ÷ (1.64 * 1.64) = 68 ÷ 2.6895 = 24.5398 Since the result (24.5398) is less than the upper limit (25), the man has a normal constitution. |
- Waistline has relation with the excessive fat of the abdomen and is also a criterion of obesity
For male, the normal standard waistline is 90 cm (38 inch), while female is 80 cm (33 inch).
If constitution exponent is 25-35, and waistline of male is over 40 inch or female is over 35 inch, it is obesity.
But chronic hepatophilic viral disease always causes flatus and the abdomen intumesces. One must exclude the possibility of having liver disease before calculating waistline.