How to Calculate Body Mass Index (BMI)?
The formula to calculate Body Mass Index is as follows:
BMI = Weight (kg) / Height² (m²)
Example:
If a person weighs 70 kg and is 1.75 m tall, the BMI is calculated as:
BMI = 70 / (1.75 × 1.75) = 22.86
This result indicates that the person falls into the “normal weight” category.
Why is Body Mass Index Important?
Also known as BMI, the body mass index is used to evaluate whether an individual’s body weight is within a healthy range. Through BMI:
-
Overweight or underweight conditions can be identified,
-
The risk of obesity can be assessed,
-
A preliminary estimation of the likelihood of chronic diseases such as diabetes and hypertension can be made.
Body Mass Index Values and Their Meanings
The table below shows the BMI value ranges and their meanings:
| BMI Value |
Classification |
Explanation |
| Below 18.5 |
Underweight |
Low body fat percentage. Possible nutritional deficiencies. |
| 18.5 – 24.9 |
Normal weight |
Healthy weight range. |
| 25.0 – 29.9 |
Overweight |
Weight control is recommended. |
| 30.0 – 34.9 |
Class 1 Obesity (Mild) |
Health risks related to obesity begin. |
| 35.0 – 39.9 |
Class 2 Obesity (Moderate) |
Increased risk of heart disease and diabetes. |
| 40.0 and above |
Class 3 Obesity (Severe) |
Very high risk of serious health problems. |
What is Ideal Weight Calculation?
Ideal weight is a healthy body weight determined by considering an individual’s height, age, gender, and overall health condition. Using a BMI calculator, a person can understand how close or far they are from their ideal weight. This information plays an important role in planning weight loss or gain programs.
How to Use a BMI Calculator
With an online BMI calculator, individuals can quickly find out their body mass index by entering only their height and weight. These tools provide more meaningful results when used alongside recommendations from health professionals.
BMI Assessment According to Age
The BMI calculation method used for adults is general and does not directly change with age. However, since muscle mass may decrease with age, methods like body fat percentage calculation should also be used alongside BMI.
BMI Calculation in Children
For children, BMI assessment is done according to age and gender. The evaluation is made using percentile curves determined by the World Health Organization (WHO). “Children’s BMI calculators” are designed to perform these special assessments.
Difference Between Body Fat Percentage and BMI
BMI is based only on weight and height ratio. Individuals with high muscle mass may have a high BMI, but this does not necessarily mean they have excess fat. Therefore, calculating body fat percentage provides a more accurate assessment for athletes.
Obesity Calculation and Risk Factors
Individuals with a BMI over 30 are considered “obese.” Obesity calculation is a crucial first step in preventing chronic diseases. Alongside BMI, other anthropometric measurements like waist circumference should also be considered.
What is BMI and How is it Interpreted?
BMI is a calculation method that helps determine whether an individual is overweight, normal weight, or underweight. Values are classified into specific ranges, and health risks are assessed accordingly.
What Should the BMI Be?
Generally, a healthy individual’s BMI should be between 18.5 and 24.9. However, this value may vary depending on the person’s age, gender, and muscle/fat ratio.
What Should be Done to Lower BMI?
Lifestyle changes such as balanced nutrition, regular exercise, and adequate sleep play an important role in bringing BMI into the ideal range.
Is BMI Calculation the Same as Ideal Weight Calculation?
No. While BMI is a general health indicator, ideal weight calculation may be based on more comprehensive parameters. BMI helps understand if a person is close to their ideal weight.
Summary
Body Mass Index (BMI) is a practical and scientific method used to evaluate individuals’ health status. It plays an important role in identifying underweight, overweight, and obesity conditions. However, BMI results are not absolutely accurate for every individual; therefore, they should be used together with additional measurements and assessments by health professionals.
BMI calculation serves as a guide for anyone aiming to set and maintain healthy living goals.