Is BMI Really A Good Measure Of Your Health?

What Does Your BMI Mean?

BMI is a calculation of your size that takes into account your height and weight. It expresses the relationship between your height and weight as a single number that is not dependent on frame size. More specifically, to calculate your BMI, you divide your weight in kilograms by the square of your height in meters.

A normal BMI is between 18.5 and 25. A person with a BMI higher than 25 is considered overweight. A person is considered underweight if the BMI is less than 18.5.

As with most measures of health, BMI is not a perfect test. Results can be thrown off by pregnancy or high muscle mass, and it may not be a good measure of health for children or the elderly. So then, why does BMI matter? In general, the higher your BMI, the higher the risk of developing a range of conditions linked with excess weight, including:

– Diabetes

– Arthiritis

– Liver disease

– Different types of cancer (such as breast, colon, and prostate)

– High blood pressure

– High cholesterol

– Sleep apnea

BMI Doesn’t Take Gender Into Consideration.

If a man and woman are the same height and weight, they have the same calculated BMI. The problem is women have a higher body fat percentage than men. On average, a man and woman of similar height and weight might have a body fat percentage that differs by 10% or more. Based on BMI, a man with 15% body fat and a woman with 30% body fat are at similar risk based on BMI.

BMI Doesn’t Take into Account WHERE You Store Fat

As discussed, two people with different body fat percentages can have the same BMI, as long as their height and weight are the same. BMI as a measurement also doesn’t take into account body fat distribution. Studies now show that where you carry your body fat matters and you’re at higher risk of health problems if you store a higher proportion of body fat around your waist.

In contrast, fat stored around the hips and thighs doesn’t appear to carry the same risk. So, two people can have the same BMI, yet one will be at higher risk of type 2 diabetes and heart disease because of where they store their fat.

Should We Listen To The BMI Numbers?

Research suggests that BMI alone frequently misclassifies metabolic health, which is linked to how much fat a person has and how it is distributed throughout the body. BMI doesn’t distinguish between bone, muscle, and fat and, instead, weights them all equally. We know in terms of health risk, they’re not the same. Plus, a BMI measurement gives no indication of body fat distribution.

When measuring BMI alone it would not be expected to identify cardiovascular health or illness, and while cardiovascular health is important, it’s not the only measure of health. However, BMI may be more useful at predicting future rather than current health. Those who are healthy and overweight or obese are more likely to develop diabetes or other negative health consequences over time.

As a single measure, BMI is not a perfect measure of health. But it’s still a useful starting point for important conditions that become more likely when a person is overweight or obese. 

What Else Can I Use To Measure My Health?

Our Inbody Body Composition Manager is a great tool to get a complete breakdown of your body. Come in to any of our locations for a scan, and receive an immediate print off with your results. Our staff is also trained to go over these results with you to make sure you know what they mean.