8 ms·

I would rather see something on body fat percentage. BMI is not an ideal measurement in terms of health for a lot of body types.

Kurtz79 13y ago
I don't agree. BMI accounts for height by its own definition and for health/body types by leaving large margins for the definitions of normal/overweight/obese. It might not be a precise measure for some individuals (athletic, heavy muscled males) but what percentage are those in the context of a whole country ? As an average/indicator over a large sample is perfectly acceptable, in my opinion.
- Theriac25 13y ago
  I disagree. A 182cm (6ft) person can weigh only 82 kg (~180lbs) to be not considered overweight. If you have any amount of muscle and don't have a single digit bodyfat percentage, you're easily overweight according to BMI. And it only gets worse when you get taller. Similarly, short people can be seriously fat and not be considered overweight according to BMI. The exponent in the BMI formula should be larger than 2.
  - tekalon 13y ago
    I don't know. My husband is 6'4" and is scrawny build but with a bit of extra around the middle and he can feels 'overweight' right around the same time he hits the BMI level. I'm 4'11" and definitely feel the that BMI is correct with how my body feels.
- yummyfajitas 13y ago
  BMI is const x weight/height^2. Volume is proportional to height^3, unless you believe tall people grow in only 2 directions. So BMI ~ height. That's why most of the NBA is obese.
  - DanBC 13y ago
    Everyone mentions athletes whenever BMI is mentioned. Most people are not athletes. Most people do very little exercise. When using BMI for an individual you ask them if they do any exercise, but for populations it's fine.
    - yummyfajitas 13y ago
      I mention the NBA due to height, not athleticism. BMI is an overestimate for tall people and an underestimate for short people, due to the scaling law I described.
      - DanBC 13y ago
        Most people are not NBA tall, so luckily it's no such a problem for BMI over mass populations.
  - ronaldx 13y ago
    Do humans grow in 3 dimensions? Research suggests the power should be slightly less than 2. e.g. http://www.ncbi.nlm.nih.gov/pubmed/15761809 http://www.ncbi.nlm.nih.gov/pubmed/15761809 Some groups of athletes list overweight because muscle is very dense - BMI doesn't distinguish between muscle and fat. However, this does not mean that BMI is useless even here - overweight athletes often suffer similar medical conditions as overweight people generally.
opinali 13y ago
A much better metric than BMI is the Waist-to-Height Ratio: https://en.wikipedia.org/wiki/Waist-to-height_ratio https://en.wikipedia.org/wiki/Waist-to-height_ratio

Kurtz79 13y ago

I don't agree. BMI accounts for height by its own definition and for health/body types by leaving large margins for the definitions of normal/overweight/obese. It might not be a precise measure for some individuals (athletic, heavy muscled males) but what percentage are those in the context of a whole country ? As an average/indicator over a large sample is perfectly acceptable, in my opinion.

Theriac25 13y ago
I disagree. A 182cm (6ft) person can weigh only 82 kg (~180lbs) to be not considered overweight. If you have any amount of muscle and don't have a single digit bodyfat percentage, you're easily overweight according to BMI. And it only gets worse when you get taller. Similarly, short people can be seriously fat and not be considered overweight according to BMI. The exponent in the BMI formula should be larger than 2.
- tekalon 13y ago
  I don't know. My husband is 6'4" and is scrawny build but with a bit of extra around the middle and he can feels 'overweight' right around the same time he hits the BMI level. I'm 4'11" and definitely feel the that BMI is correct with how my body feels.
yummyfajitas 13y ago
BMI is const x weight/height^2. Volume is proportional to height^3, unless you believe tall people grow in only 2 directions. So BMI ~ height. That's why most of the NBA is obese.
- DanBC 13y ago
  Everyone mentions athletes whenever BMI is mentioned. Most people are not athletes. Most people do very little exercise. When using BMI for an individual you ask them if they do any exercise, but for populations it's fine.
  - yummyfajitas 13y ago
    I mention the NBA due to height, not athleticism. BMI is an overestimate for tall people and an underestimate for short people, due to the scaling law I described.
    - DanBC 13y ago
      Most people are not NBA tall, so luckily it's no such a problem for BMI over mass populations.
- ronaldx 13y ago
  Do humans grow in 3 dimensions? Research suggests the power should be slightly less than 2. e.g. http://www.ncbi.nlm.nih.gov/pubmed/15761809 http://www.ncbi.nlm.nih.gov/pubmed/15761809 Some groups of athletes list overweight because muscle is very dense - BMI doesn't distinguish between muscle and fat. However, this does not mean that BMI is useless even here - overweight athletes often suffer similar medical conditions as overweight people generally.

opinali 13y ago

A much better metric than BMI is the Waist-to-Height Ratio: https://en.wikipedia.org/wiki/Waist-to-height_ratio https://en.wikipedia.org/wiki/Waist-to-height_ratio