A World Health Organisation report lists New Zealand as the 12th fattest nation on earth out of 197 countries. Why? According to its statisticians 27 per cent of Kiwis are classed as obese because their body mass index is 30 or greater.
What does this really mean? Should we be worried?
Body mass index (BMI) is a calculation based on your weight and height, not a measurement of body fatness. Are we really porkers or the victims of a statistical beat-up?
What BMI best represents is your shape. A high BMI, say 35, indicates you possess a large volume to surface area ratio, making you wide in the middle like a rugby ball. A low BMI, say 18, means you're most likely long and thin. Much like a pencil. What public health scientists know is that if you resemble a rugby ball, you're more likely to carry a lot more body fat than a 'pencil'.
Carrying too much body fat is associated with a greater chance of dying from a heart attack, kidney failure, or getting diabetes and some cancers. When our fat stores become too full, the fat molecules spill over into the circulation, causing other tissues like muscle, the liver and even the heart to accumulate fat, upsetting their normal function. One of the most common results is that your muscle stops using glucose from the blood while your liver is encouraged to produce glucose. That's why obesity makes it tough to control blood glucose, leading too often to diabetes.
