Nutrition For Runners 

Stupid BMI
I had a rant on Tuesday about the Courier Mail's story on the BMI (Body Mass Index), and how the Australian Bureau of Statistics have come out and said that many Australians are now classed as overweight or obese.

Don’t get me wrong, I am not saying that our society is not getting fatter and obesity is a real problem, not only in the western world but now third world countries are showing signs of becoming obese and suffering from the deadly diseases of being overweight.

But when they start quoting that Jonathon Brown (AFL legend) is overweight, that is when I start to get angry. One look at Jonathon Brown in the flesh or watch him play four quarters of top level football  and you would know that he is not overweight and is one of the fittest guys out there. So why does the Courier Mail state he is fat.

Well the BMI is calculated on this equation,
BMI= (Weight in Kilos) divided by (Height in Metres) X (Height in Metres)
Jonathon Brown is 104kgs and 1.95 metres
So the equation is 104 ÷ (1.95 X 1.95) = 27.3 BMI

The BMI scale is as follows
Underweight Below 18.5
Normal 18.5 to 24.9
Overweight 25-29.9
Obese 30 and higher

If you go by the BMI scale, half of the rugby players are obese and the rest are categorised as overweight. Anna Meares (Gold medal cyclist) is overweight; Ky Hurst, 7 times iron man winner is overweight; at the height of his basketball playing career Michael Jordon would have been classified as obese according to his BMI results…how can this be you ask?

The latest BMI results the ABS have come up with are-
In 2011-12, 63.4% of Australians aged 18 years and over were overweight or obese, comprised of 35.0% overweight and 28.3% obese. A further 35.2% were of normal weight and 1.5% were underweight.
The prevalence of overweight and obesity has increased in Australia over time, from 61.2% in 2007–08 and 56.3% in 1995.

The BMI was introduced 200 years ago by a Belgian physicist named Lambert Adolphe Jacques Quetelet.  He produced the formula to give a quick and easy way to measure the degree of obesity of the general population to assist the government in allocating resources. However, when talking about the BMI there are some crucial points that should be noted-

Point 1-The BMI is all about height.
The BMI measures two dimensions, height and weight, however it doesn’t take into account the humans are three dimensional, and the third space is filled with many different things! BMI  doesn’t take into account body composition, body shape or genetics. Muscle is very dense and a lot heavier than fat. Big, long, strong bones weigh heavier than shorter, weaker bones. Even the size of a person’s head can vary by kilos! All this often means that a muscular, low fat, strong boned person will have a high BMI, and be classified as overweight or obese.

I think statistics are vital  and a good way to measure how a society is going and where our resources need to be doled out. However, shouldn’t those statistics be accurate and show the real picture, and not use an out dated 200 year old mathematical equation.

Apparently Australians are eating better and exercising more however we are getting fatter…but are we? Or are we building muscle and strength and getting healthier in our heaviness?

Also we are growing  up as well as out. Our population is getting taller. When the BMI was invented by the physicist 200 years ago, the average height of an English man was 170cm and for an Englishwoman 152cm. Australians average height today is 176cm for males and 162cm for females.

On average, Australians are growing taller and heavier over time. Between 1995 and 2011-12, the average height for men increased by 0.8 cm and for women by 0.4 cm, while the average weight for men increased by 3.9 kg and for women by 4.1 kg. It is very common for children to outgrow at least one of their parents, so that rise will continue into the future.

So we are growing, our bones are growing and the muscles attached to those bones are growing, all of this contributes to our bigger BMI’s

Point 2- The BMI does not differentiate between apples and pears
The distribution of body weight, or more generally the shape of the body is a key predictor of health risk. It is now well established that individuals who deposit much of their body weight around their midsection, the so called apple-shaped, are at much greater risk of disease and early mortality in contrast to the so called pear-shaped, who carry their weight more peripherally, particularly in the lower body.
A better way to check this risk is to measure the waist circumference

Current research suggests that a waist circumference of above 94cm in men and 80cm in women show an overweight level and above 88 cm in women and 102cm in men denotes abdominal obesity. A larger waist circumference can lead to a greater risk of diabetes, cardiovascular disease, mortality, and numerous other health outcomes. This all suggests, waist circumference may be a more important measure of obesity and health risk than BMI.

In 2011-12, 60.3% of men aged 18 years and over had a waist circumference that put them at an increased risk of developing chronic diseases, while 66.6% of women had an increased level of risk.
On average, men aged 18 years and over had a waist measurement of 97.9 cm, while women had a waist measurement of 87.7 cm. Between 2007-08 and 2011-12, average waist measurements increased by 1.7 cm for men and 1.9 cm for women.
In total, 61% of Australians were overweight or obese. This rate was higher for men (68%) than women (55%), and higher for older people than younger people.

For an accurate waist measurement:
• Measure directly against your skin
• Breathe out normally.
• Make sure the tape is snug, without compressing the skin.
• The correct place to measure your waist is horizontally halfway between your lowest rib and the top of your hipbone. This is roughly in line with your belly button

Point 3- What about what we can’t see
Mostly we know if we are overweight or have put on a few kilos. We can see it, feel it, our clothes are tighter and maybe we don’t feel as fit or healthy. However, what about all the things we can’t see and feel, the stuff that is going on inside of us.
Fat isn’t just on the outside, visceral fat can line our organs and block our blood vessels. Cholesterol is a fatty substance in our blood that can line and block our arteries, but we cannot see it or feel it from out here! Our blood could be really struggling to get through or pump to all areas of the body and often we don’t even know, and the BMI is not going to tell us that.

High blood pressure is an important risk factor for heart disease, stroke and other cardiovascular diseases.

According to WHO guidelines, a person is defined as having high blood pressure if their systolic or diastolic blood pressure is equal to or greater than 140/90 mmHg.

In 2011-12, just over 3.1 million people aged 18 years and over (21.5%) had measured high blood pressure. Overall, men were more likely to have high blood pressure than women (23.6% and 19.5% respectively), while the proportion of Australians with high blood pressure increased with age. Around 42.5% of persons aged 65 years and over had measured high blood pressure, compared with 6.0% of people aged 18-24 years.

However, what really irks me about the BMI is when the ABS releases their health statistics for Australia, the media always jump on it, find some of our top athletes and then out them as being fat and obese. I get so angry about the misleading information that goes on about our health and the health industry. Instead of showing real obese people, they flash up healthy fit individuals which leads to many overweight and obese people who really are in danger of health problems to say ‘well if Jonathon Brown is overweight what hope is there for the rest of us, might as well crack open another tinnie and bag of chips’

When it comes to health and testing, there is a whole process you need to go through to make sure you are fit, healthy and disease free
*Yes you should be aware of your BMI
*You should know your body fat levels; basic scales can give you a reading, although it will be a general reading it will still give you an idea of where you are on the bodyfat  scale
(The true reading of body fat levels is done by being weighed  underwater! Or a skin fold test can be accurate as well)
*You should know if your waist circumference is in a healthy range
*You should know your body shape- it more than likely is a similar shape to one of your parents, and cannot be changed, but remember obesity is not a body shape

Then there are other things you need to know, that a doctor or pharmacist can help you with
*Your doctor or pharmacist can read your blood pressure- and you should also know if you have a family history of high blood pressure or stroke or heart disease
*Your doctor can order a blood test for your cholesterol- and you should also check if any family members have a high reading as well
*If you have a family history of diabetes or you are overweight or obese you should get your blood sugar levels tested, your doctor or sometimes pharmacists can do this simple test

Bottom Line for this tip…and there always is one...
The government, their surveys or the media are not responsible for your health or cannot tell you if you are fat, skinny or obese…only one person is responsible for your health and weight…YOU

It’s not up to your doctor, your partner, your mother (if you are an adult) to remind you to get a health check or keep an eye on your health or weight…you should consistently be aware of all the things going in inside and outside of you.

I know all of the things listed above about myself..I know my family history of illness and disease, my body shape (same as my mums and grandmothers), I remember my last blood pressure reading (often low) from the doctor; I know my cholesterol reading as my mother has a high level so the family is told to get tested regularly...and yes I know my BMI-19

I dont leave all these things to chance and I dont expect anyone else to take note of them or care that much...that is why we have to do it for ourselves...and another thing I do know for sure...Jonathon Brown is not a fatty!




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