Skip to main content


Body Mass Index (BMI): What is it and why is it important?

Nutrition is a major problem for children living in poverty. Many do not have enough food and resort to eating whatever is available. For instance, scavenging for food from trash is commonplace. As a result, a healthy diet is a reality only for a lucky few. Therefore, it is necessary to measure the BMI of children living in poverty, so that any problems can be recognised and used to identify the best way to help them.

What is Body Mass Index (BMI)?

BMI is an indicator used to measure the ratio between someone’s weight and height and can be used to determine whether a person is a healthy weight, overweight or underweight. Unlike in adults, the healthy amount of body fat for a child changes with age and varies according to their gender. As a result, BMI measurements in children are always interpreted in relation to their age and gender.

Why is it important?

Since BMI gives an indication as to whether a child has healthy amount of body fat for their age and gender, it can be used to identify who is vulnerable to future health risks. Children who have too much or too little body fat for their age or gender are incredibly at-risk. They are likely to be stunted in both physical and mental development and can lose up to ten years on their life expectancy.

How does it affect our work?

Our programme partner Fairplay is using body mass index as a key indicator to measure progress of the work we’re co-funding. If you would like to find out more about our partnership project ‘Helping 100 Children At-Risk in Payatas, The Philippines’, please check out our work. We hope that through our work in Payatas and beyond we will be able to improve the BMI of children living in poverty across the world, so that they stay within the range that is ‘normal’ for their age and are not exposed to future physical and mental health risks.


  1. Fairplay For All Foundation (2018) Helping 100 Children At-Risk: How Much does Regular Sport, Nutrition, and Social Groups Improve the Well-being of Children in Payatas? Unpublished.
  2. NHS UK: What is the body mass index (BMI)? Jul 2016.