Introduction to the formula for calculating the weight-to-height ratio of body mass index
Body mass index reflects the ideal and simple indicator of standard weight, and can be expressed by the relationship between the standard calculation method of height and weight. Female normal weight = height – 105 ; male normal weight = height – 100
BMI for adults
BMI This concept was first proposed by the Belgian generalist Kettler in the mid-19th century. It is calculated as: Body Mass Index (BMI) = Weight (kg) / Height (m) squared. The ideal BMI is 22.
BMI – Men: BMI – Women: Underweight – Below 20 Underweight – Below 19 Moderate – 20-25 Moderate – 19-24 Overweight – 25-30 Overweight – 24-29 Obese – 30-35 Obese – 29-34 Very obese – above 35 Very obese – above 34
Because of errors, BMI is only one of many criteria for assessing an individual’s weight and health. The National Institutes of Health (NIH) recommends that physicians assess whether a patient is overweight based on the following three factors.
BMI waist circumference – measures abdominal fat and risk factors for obesity-related diseases such as high blood pressure, high LDL (“bad”) cholesterol, low HDL (“good”) cholesterol, high blood sugar, and smoking .
Because BMI doesn’t take into account a person’s fat percentage, a person with an overweight BMI may not actually be obese. For example, a person who is exercising will have a BMI of over 30 due to a heavy percentage of muscle mass in his body weight. If their body fat percentage is low, they don’t need to lose weight.
Children’s BMI values
Children’s BMI values are not just for adults. For growing children, we can also use their BMI to estimate whether they are overweight. The above BMI calculation formula is also applicable to people aged 2-20, but their indicators of overweight and underweight are not determined by a fixed BMI value. This is because children in different regions have different growth rates. If a fixed value is used, it is easy to make wrong judgments.
Many countries and regions conduct annual statistics on the height and weight of local children. These statistics can be converted into BMI values, and then the BMI value distribution of local children can be calculated. Based on this distribution, the local health government can calculate the overweight and underweight indicators of local children. Generally speaking, the average BMI value and its standard deviation will be used, and then the highest 5% and the lowest 5% of the normal distribution will be calculated as the indicators of overweight and underweight. On the other hand, children whose BMI values are in the 85%-95% range of the normal distribution are at risk of being overweight.
Chinese Adult Body Index
Although the World Health Organization has established obesity standards, it is based on research data of Western populations. Not suitable for Asian crowd. Professor Zhou Beifan, from the Epidemiology Research Office of Fuwai Cardiovascular Hospital, Chinese Academy of Medical Sciences, wrote in the just-published issue A7 of “Popular Medicine” that the China Obesity Working Group based on the summary analysis report of the Chinese population in the 1990s, For the first time, the obesity standard suitable for Chinese adults is proposed:
Body mass index greater than or equal to 24 is overweight, and greater than or equal to 28 is obese; male waist circumference is greater than or equal to 85 cm, and female waist circumference is greater than or equal to 80 cm as waist obesity standard.
At present, the international body mass index (BMI) is used to measure obesity. Body mass index is equal to weight (kg) divided by height (meters) squared. Waist circumference is an important indicator of abdominal obesity, which reflects the degree of abdominal fat accumulation, which is related to a series of metabolic abnormalities.
This summary analysis report by the China Obesity Working Group shows that an increase in body mass index is associated with an increase in the incidence of coronary heart disease and stroke, and overweight and obesity are independent risks of coronary heart disease and stroke. factor. For every 2 increase in body mass index, the relative risk of coronary heart disease, stroke, and ischemic stroke increased by 15.4%, 6.1%, and 18.8%, respectively. Once the BMI reaches or exceeds 24, the probability of developing serious health-threatening diseases such as hypertension, diabetes, coronary heart disease and dyslipidemia increases significantly.
