Paul Little: It's fashion, not magic, folks

There is a free app, of course, but the Fitbit that does the work costs you $229. Photo / AP

You'll have seen a Fitbit by now - a wrist band worn by people, many of them sane, who think an accessory will make them healthier. In essence, they are a form of cyber snake oil.

And people are swallowing it big time. Fitbit launched on the New York Stock Exchange last year with an opening price of $20 a share and finished the day at just shy of $30.

So what does it do? If you're a Fitbit-wearer you can, for instance, set the number of steps you want to walk in a day and be told when you've reached that number or be given a hurry-up if it looks like you won't.

The different models have names like Force, Charge, Surge and Blaze - designed to make you feel you're losing weight just by looking at them. It also has one capacity that is guaranteed to win the hearts and credit card details of contemporary consumers - you can sync it to a device!

There is a free app, of course, but the Fitbit that does the work costs you $229.

The human body comes equipped with mechanisms for telling whether you're exercising enough -they're called sweating and panting. Unfortunately, a consumerist society believes only what is paid for has any value - and the more you pay, the more valuable it is.

The Fitbit's most extraordinary function is that it deludes wearers into thinking they are doing something that will make them healthy.

There is an unfit army of people who have convinced themselves they are going to great lengths to stay healthy.

And there is a supply division eagerly bringing up the rear, selling products that will bolster their delusion.

"Look, I must be healthy. I'm wearing a Fitbit ... see - it has numbers on it that change. Even when I'm not doing anything I'm doing something! It's a miracle!"

The high science behind this technology has encouraged a superstitious faith in it: "I must be healthy. I'm wearing something on my wrist that tells me so."

This is the greatest gift for the exercise-averse since the invention of television.

A little realism in public conversation about these issues might help. It would, for instance, be a kindness if public figures who disappear briefly and return to the limelight a slim shadow of their former selves were candid about the surgery that had effected this, rather than claiming they "just ate sensibly".

Fitbits have names like Force, Charge, Surge and Blaze - designed to make you feel you're losing weight just by looking at them.

We also need to stop kidding ourselves about food products proclaimed to be "natural" and "healthy" that are little more than sugar-delivery mechanisms.

For years people believed muesli and yoghurt must be healthy because they looked healthy, not bothering to note how much fat and sugar the commercially produced packets contain. Fitbits encourage such self-deception: "I can have a pie for lunch because, look, I'm wearing a Fitbit. I'm health-conscious."

Equally cynical are the diet books produced in ever greater numbers, each bringing the latest breakthrough about how our bodies really work.

Few come with a money-back guarantee - but then, few are used by people to lose weight.

No less cynical are the fitness clubs that happily take people's money then show no interest in encouraging them to exercise properly. But why should they?

"I must be fit," crow the gullible hordes. "I go to the gym."

The fatal misconception is that you can buy good results rather than earn them. It may be good for business, but it's not good for our health.

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