Body Mass Index (BMI) is a numerical value derived from an individual's weight and height. It's one of the most widely used tools to assess whether a person has a healthy body weight for their height.
BMI is a screening measurement that compares your weight to your height to give you an indication of your body composition. It was developed in the 19th century by Belgian mathematician Adolphe Quetelet and has become a standard tool in healthcare and fitness.
The World Health Organization (WHO) classifies BMI into the following categories:
BMI is important because it can help identify potential health risks associated with being underweight, overweight, or obese. Research has shown correlations between BMI and various health conditions:
While BMI is a useful screening tool, it has several important limitations:
BMI doesn't distinguish between muscle mass and fat mass. A muscular athlete might have a high BMI but low body fat percentage.
BMI doesn't indicate where fat is stored in the body. Abdominal fat (visceral fat) is more harmful than subcutaneous fat, but BMI can't differentiate between the two.
BMI doesn't account for differences in body composition related to age and gender. Older adults and women naturally have higher body fat percentages than younger people and men at the same BMI.
Some ethnic groups may have different health risks at the same BMI levels. For example, people of Asian descent may have higher health risks at lower BMI values.
Healthcare professionals often use BMI alongside other measurements for a more complete health assessment:
BMI should be used as a starting point for health discussions, not as a definitive diagnosis. Here's how to use it effectively:
Use our free BMI calculator to find out your body mass index and understand what it means for your health.
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