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Body Mass Index (BMI)

The Body Mass Index (BMI) is a measurement tool that compares your height to your weight and gives you an indication of whether you are overweight, underweight or at a healthy weight for your height. You can find a body mass index calculator on many websites such as www.bmicalculator.ie.Or you can calculate your BMI manually BY following the steps below:

Formula: weight (kg) / [height (m)]2

With the metric system, the formula for BMI is weight in kilograms divided by height in meters squared. Since height is commonly measured in centimetres, divide height in centimetres by 100 to obtain height in meters.

Example: Weight = 68 kg, Height = 165 cm (1.65 m)
Calculation: 68 ÷ (1.65 x 1.65 ) = 24.98

The BMI calculation is only for adults. Ask your doctor for help if you think you child is overweight.

Recent research has found that the waist to hip ratio provides a much better indicator than BMI of whether an adult has too much body fat. Higher ratios indicate an increased risk of stroke, diabetes, and heart attack. To determine if you have a healthy waist to hip ratio, use a measuring tape to measure the circumference of your hips at the widest part of your buttocks. Then measure your waist at the smaller circumference of your natural waist, usually just above the belly button. To determine the ratio, divide your waist measurement by your hip measurement.

Waist measurement in cm ÷ Hip measurements in cm = Waist to hip ratio.

Generally the waist to hip ratio should not exceed about 0.9 for men and 0.8 for women. Research shows that people with "apple-shaped" bodies (with more weight around the waist) face more health risks than those with "pear-shaped" bodies who carry more weight around the hips.

Copyright © Dr. David Buckley