Hey there Guys,
Today I was alerted to an article in my local newspaper about how the current measure of obesity “body mass index” AKA “BMI” is not a very useful tool for telling health…
As discussed with regards to Robert, pictured above:
He is just an average Aussie bloke, tipping the scales at 83kg and standing 175cm tall. Yet this man is apparently fat.
While Robert Sheahan’s physique may appear normal to most, he is overweight according to the medically recognised body mass index (BMI). The average Australian man now weighs 85.2kg, up from 82kg in 1995. Women are also heavier, with the average now 70.1kg compared to 67kg.
Ask any doctor if BMI is useful and almost all will report that it’s pretty crap. BMI is calculated by taking your weight and dividing it by your height squared. It does not take body composition into account so the very muscular and the very thin can have unusual results.
In this case Robert’s BMI is 27 which is pretty much the middle of the “overweight” range. From an individual perspecitve BMI is useless. If a population’s BMI is getting higher and higher that may be useful but today I wanted to talk about one measure that is a much better measure of health.
How your waist measurement is a much better predictor of health.
Since my thirties I hate to admit I had been developing a bit of a belly. What used to be a 32 inch waist had ballooned out to 40 inches at my heaviest. I’m currently snug in a 34″ pair of jeans thanks to eating better and regular aqua aerobics.
When I hit the big 40″ size I knew that something had to change.
I’d go shopping for clothes and suddenly have to go to the rack down the back of the shop, the shirts I wore though med school were “suddenly” straining at the buttons. Don’t even ask how short of breath I was getting lacing up my shoes.
There I was a family doctor, sitting telling my patients they had to work on weight loss while I was jiggling away when I sat down at my desk. Ummm yes I did feel like a hypocrite.
One of my work colleges “lovingly” slipped a research paper onto my desk. What I read scared me.
Most doctors are pretty well versed with the standard risks of a big belly, or “visceral obesity” in doctor speak. We know that when the belly is growing there is a layer of fat covering the internal organs that is growing as well. As this fat is easily accessed by the blood steam there is increased risk of fatty clots in the heart and arteries. This can lead to high blood pressure and an increased risk of heart attacks.
What is scary is the latest research that shows this fat layer can also store and release hormones. These hormones can make insulin less effective which can develop into diabetes.
Disturbingly this fat layer is also associated with increased risk of cancer. In particular liver, bowel and pancreatic cancer rates are double in men who have abdominal obesity. The New England Journal of Medicine reports that 14% of cancer deaths in males in the USA in 2011 were attributed to being overweight.
The good news is that the evidence shows that by reducing the waist line the risk of cancer reduces back to the level of people who had never been overweight.
So what is considered an ideal waist measurement?
Evidence from Australia and the USA indicated that waist measurements in men of more than 94 cm (or 90cm if you are Asian) has increased risk for cardiac disease, diabetes and cancers.
As your waist line increases this risk also increases. The bigger your waist the bigger the risk.
So where do I start from here?
The first step to reducing your risk is to get a good measurement of your waist line. All you need is a tape measure.
To measure your waist, simply pass the tape around your waist. You want the tape to sit in a line that is in the middle between the bottom of your ribs and the top of your hips.
To make life a little easier I have created the following video to demonstrate exactly what I mean.
So guys, ditch the whole BMI measurement and grab yourself a tape measure.
As I say to my patients, if your underpants are getting looser, you’re working in the right direction.
Yours in good health.
Dr George
Leave a Reply