"Focusing on weight and weight loss is demotivating for people and it makes it harder for people to look after themselves in the best way they can."

For a self-described 'fitness motivator', John Burk has an interesting approach. The US Iraq war veteran recently made headlines when he took to YouTube to tell everyone how much he's repulsed by fat people.

Burk began his rant by claiming "scientific studies have shown that it is not healthy to be overweight," and being overweight is simply a result of "sheer f--king laziness".

What is perhaps most telling about Burk's rant is not his prejudices or his misunderstanding of the word 'motivation', but his limited knowledge of science.

To Burk and many other people — including some well known fitness celebrities and public health bodies — weight is black and white: Fat is always unhealthy and weight loss is a simple matter of discipline and choice.


But science is not on their side, and it hasn't been for quite some time.

In the same month that Burk made his toxic little video, the American Journal of Public Heath published a study which found long-term weight loss is all but impossible for most people.

The researchers from Kings College Cambridge looked at ten years worth of data from 278,982 people in the UK health records and determined that women in the 'obese' BMI category have a 1 in 124 chance of reducing their BMI to the 'healthy' BMI range, or a 1 in 677 chance if they are 'severely obese'.

A man with an 'obese' BMI has a 1 in 210 chance of achieving a BMI in the 'healthy' range. This becomes a 1 in 1,290 chance if he's 'severely obese'.

If you subscribe to Burk's worldview, you would have to conclude that the one woman out of 124 and the one man out of 210 who are able to lose weight are more disciplined and morally superior to all the rest who couldn't lose weight. A tiny minority made good choices while the all others made 'bulls--t excuses'.

But there's no evidence to support this conclusion.

The study's findings won't come as news to anyone who, unlike Burk, has actually bothered to look at the science. According to Dr Rick Kausman, author of If Not Dieting, Then What?, researchers have known for decades that weight loss is not a simple matter of choice.

"We don't need any more studies to show that almost everyone who attempts to lose weight regains it again, and between one third and two thirds of dieters end up heavier as a result of dieting," says Dr Kausman — who has run a weight management clinic for 25 years and is a fellow of the Australian Society for Psychological Medicine.

"This continual obsession about the so-called 'ideal weight' increases weight stigma and weight shame. Not only is that inappropriate, but there is heaps of evidence to show that focusing on weight and weight loss is demotivating for people and it makes it harder for people to look after themselves in the best way they can."

As much as people like Burk might like to reduce weight to a simple equation, scientists — actual scientists, rather than gym bros whose qualifications amount to little more than reading the slogan on their protein shake — have shown that losing weight is mind-bogglingly complex.

Dr Kausman says that the most likely explanation as to why some people are able to lose weight is that they are evolutionary anomalies.

"In times of famine — or weight loss dieting — our bodies are designed to do whatever they can to hang on to our energy stores. Research has shown that one year after a weight-loss diet, all the hormones that kick in to keep us alive by preserving energy are still in play."

The Kings College research highlights just how ignorant, cruel and futile it is to abuse people for being fat. Nevertheless, proving yet again how difficult it is to lose weight may be counter-productive.

Dr Kausman says that everyone should forget about weight and focus on wellness instead – that includes the John Burks of the world, the medical profession, researchers who keep conducting weight loss studies, and the general public.

If we change the goal from weight loss to doing the best we can to eat well and move our bodies instead, then we'll have a much better shot of achieving it.

While fat shamers like to think that there is a relationship between hurling abuse and weight loss, the science says otherwise. And all the YouTube rants in the world are not going to change that.

Kasey Edwards is a writer and best-selling author. www.kaseyedwards.com