The above variation of a popular campfire song came to mind when I thought about the latest health campaign (in September 2003) to make Singaporeans aware of their BMI, or body mass index.

It’s very simple, according to press and television advertisements. All you need is a weighing scale, a measuring tape and a calculator. You measure your weight in kilograms, then divide it by the square of your height in metres.

Simple? Try explaining that to the fat lady who sells pig organ soup!

There are lots of far simpler ways to tell whether you are fat:

• look into the mirror;
• look at your clothes label (XL? XXL?);
• feel if your clothes are getting tight;
• compare yourself with models;
• weigh yourself (if over 100kg, you are definitely fat unless you are a professional basketballer);
• measure your waist (36 inches is the ideal measurement for women’s busts, not men’s tummies!),
• pinch your waist;
• pinch your cheeks;
• count how many chins you have, (Two? Three? Zero?)...

If you are fat, it’s obvious. You should know it without having to do work out complex mathematical formulae.

If you refuse to accept the fact, you are not being honest with yourself. In this case, you need a heart attack to jolt you into reality.

Borderline?

What if you are a borderline case?

Well, what if? Let’s say you do the calculations and discover that your BMI is 24 – nearly "overweight", but not quite. Does this mean you don’t need to take care of your health?

However, the Asian definition of "overweight" might be revised down to BMI exceeding 23. Then you will be re-classified as slightly overweight.

Will that motivate you to take greater care of your health? Or will you shrug it off since you are only a "marginal case"?

And so the BMI panders to our obsession with statistics, but is otherwise meaningless. The fatter you are, the more meaningless it gets. If you are very fat, does it matter whether you are "overweight" with a BMI of 29.9 or "obese" with a BMI of 30.1?

And if you are way, way obese, do you need a weighing scale, measuring tape and calculator before you realise you’ve got a serious problem?

I can think of only one instance where the BMI might be useful – it enables statisticians to say, for example, that "exactly 25.8 percent of the population are overweight and exactly 8.5 percent are obese" and then for other statisticians to understand exactly what that means.

Motivation

But that is for statistical research. It has nothing to do with motivating people to be health conscious. Statistics don’t motivate.

Has anyone ever decided to eat healthily after discovering how many calories there are in a plate of fried kway teow (rice noodles)? Or how much beta carotene in a carrot?

What do people do when they find out they have dangerously high cholesterol? Cut down on high-cholesterol foods? Really? Most simply take cholesterol-lowering drugs (at the risk of damaging their liver) and continue to eat the same things.

A major scientific study, published in the US recently, tells us that annual medical examinations – which produce a long list of numbers that measure the condition of the blood, heart, kidneys, liver, etc – are not that useful either. They have not reduced the incidence of illness nor have they prolonged lives.

Whether you are fat or sick, you don’t need numbers and statistics to tell you. You know. You just have to be honest with yourself about it.

Some years ago, I attended a workshop by Elaine Nussbaum, who had recovered from cancer and written a book titled Recovery.

Because she recovered through changing her diet and not through medical means, she never went for a medical check-up. And so she often gets asked, "How do you know you have really recovered? Where’s the proof?"

Her answer: "I used to be in so much pain that I could not climb the stairs. I was always tired, I had no appetite, I felt miserable, I looked terrible. Now I am full of energy, I can eat, I can run, I feel great.

And you say I need a piece of paper (with numbers and statistics) to prove that I am well?"