This post contains summarized information from an article found at PBS
How did we come to use BMI, and why is it still used?
- A mathematician designed it relating weight and height as an equation compared to a “norm”
- Used now for general population trends because it is cheap and easy and there’s nothing else
What is missing with the BMI measurement?
- Distinction of muscle versus fat
- Athletes may score higher as muscle is more dense than fat
- Location of excess weight
- Excess abdominal fat is more risky for disease than excess thigh fat
- Overall health
- Gives no information on health status
- An average BMI with multiple health conditions is less healthy than a higher BMI with no health conditions
- The average range varies as to what is considered “healthy” for reducing disease
Other issues with BMI measurements
- Insurance coverage
- There are BMI cutoffs for approving medications and surgeries
- Example: a treatment may be working, but has to be discontinued when someone reaches a certain BMI
- Eating disorders
- Must be in the underweight category to receive help, missing those who need it
- It is widely recognized that there are issues with BMI
- But there aren’t other options that are easy to use, cheap, and can apply to an entire population
- Don’t worry about BMI number too much – there’s other ways to determine a healthy weight through lifestyle choices and presence or lack of disease.
- Even though “average” BMI is 18.6-29.4, a number above or below could still be healthy for your body, race, lifestyle, age.
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