Teach my child about 'BMI or Body Fat'
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BMI or Body Fat

BMI or Body Fat

The Body Mass Index (BMI) is a common measure used to determine whether people (including children) are overweight. It is used because it is based on people's weight and height and this data is often readily available. It is measured by the following formula.

BMI = child's weight in kg / ((child's height in metres)*(child's height in metres))

It does have drawbacks (e.g. strong people with lots of muscle can have large BMI's and be incorrectly classified as overweight). However, as a general rule of thumb it is not a bad index and has its uses for adults. For adults it is not age dependent.

For children, however, deciding what an acceptable range for children has proved to be difficult for health organisations throughout the world. Even the US Government CDC (Centers for Disease Control and Prevention) has made a huge mistake and decided to classify that 5% of kids with the lowest BMIs will be classified as underweight, the next 80% of kids will be deemed normal weight, the next 10% with higher BMIs will be deemed overweight and the last 5% will be called obese. This is pathetic and idiotic and makes zero sense. But it goes to show the difficulties organisations have with BMI for children.

As a rule children's BMI's have been getting bigger and bigger over recent years as people take on less exercise and eat unhealthier food. Obviously some nations have fared better than others.

Body Fat

Body Fat percentage is a far better indicator of being overweight than BMI, especially for children. Body Fat data is not easily available to government organisations (which is why they use BMI) but for parents it is easy to analyse.

With advances in technology, we recommend you buy a good BIA (Bioelectrical Impedance Analyser). These are easy to get hold of nowadays (for example online at Amazon). Just ask your child to step on the scales and let it do the magic!

Then, once calculated, checkout these charts, values courtesy of www.tanita.com :

FEMALE

Age Underfat Healthy Overfat Obese
5 0.00 - 13.99 14.00 - 21.99 22.00 - 25.99
  • 26.00
6 0.00 - 13.99 14.00 - 22.99 23.00 - 26.99
  • 27.00
7 0.00 - 14.99 15.00 - 24.99 25.00 - 28.99
  • 29.00
8 0.00 - 14.99 15.00 - 25.99 26.00 - 29.99
  • 30.00
9 0.00 - 15.99 16.00 - 26.99 27.00 - 30.99
  • 31.00
10 0.00 - 15.99 16.00 - 27.99 28.00 - 31.99
  • 32.00
11 0.00 - 15.99 16.00 - 28.99 29.00 - 32.99
  • 33.00
12 0.00 - 15.99 16.00 - 28.99 29.00 - 32.99
  • 33.00
13 0.00 - 15.99 16.00 - 28.99 29.00 - 32.99
  • 33.00
14 0.00 - 15.99 16.00 - 29.99 30.00 - 33.99
  • 34.00
15 0.00 - 15.99 16.00 - 29.99 30.00 - 33.99
  • 34.00
16 0.00 - 15.99 16.00 - 29.99 30.00 - 33.99
  • 34.00
17 0.00 - 15.99 16.00 - 29.99 30.00 - 34.99
  • 35.00
18 0.00 - 16.99 17.00 - 30.99 31.00 - 35.99
  • 36.00
19 0.00 - 18.99 19.00 - 31.99 32.00 - 36.99
  • 37.00

MALE

Age Underfat Healthy Overfat Obese
5 0.00 - 13.99 14.00 - 21.99 22.00 - 25.99
  • 26.00
6 0.00 - 13.99 14.00 - 22.99 23.00 - 26.99
  • 27.00
7 0.00; - 12.99 13.00 - 19.99 20.00 - 24.99
  • 25.00
8 0.00 - 12.99 13.00 - 20.99 21.00 - 25.99
  • 26.00
9 0.00 - 12.99 13.00 - 21.99 22.00 - 26.99
  • 27.00
10 0.00 - 12.99 13.00 - 22.99 23.00 - 27.99
  • 28.00
11 0.00 - 12.99 13.00 - 22.99 23.00 - 27.99
  • 28.00
12 0.00 - 12.99 13.00 - 22.99 23.00 - 27.99
  • 28.00
13 0.00 - 11.99 12.00 - 21.99 22.00 - 26.99
  • 27.00
14 0.00 - 11.99 12.00 - 20.99 21.00 - 25.99
  • 26.00
15 0.00 - 10.99 11.00 - 20.99 21.00 - 23.99
  • 24.00
16 0.00 - 9.99 10.00 - 19.99 20.00 - 23.99
  • 24.00
17 0.00 - 9.99 10.00 - 19.99 20.00 - 23.99
  • 24.00
18 0.00 - 9.99 10.00 - 19.99 20.00 - 23.99
  • 24.00
19 0.00 - 8.99 9.00 - 19.99 20.00 - 23.99
  • 24.00

All children have different frames but the aim should be to keep them in the healthy zone.

Tips to help Children Lose Body Fat (assuming they are Overfat or Obese on the charts above)

  • Start making small changes straight away
  • Eat healthier food (fresh vegetables, lean meat, brown rice)
  • Take FUN exercise with your child
  • Get fitter yourself
  • Drink lots of water
  • Cut down on sugar levels (sugary drinks, candy etc.)
  • Cut down on high fat/ poor nutritional food such as pizza, burgers, chips, fries etc.
  • Cut down on processed foods

Reasons for High Body Fat

A calorific imbalance is the main reason i.e. expended energy (calories) is less than calories consumed via food and drink. The types of food and drink are very important, see our tips above.

Small changes can, over time, make a huge difference. Don't expect to see miracle improvements. The body takes a while to adjust - but if you and your child stick at it you will see changes. Try and be a role model and do these things yourself.

Conclusion

Ignore BMI and use Body Fat as your key control parameter. Then go out and make SMALL changes that will , over time, make a BIG difference to you and your child's life. And as an added bonus if you do it together , you may have some fun and grow closer!