Is 'slow and steady' weight loss the best approach?

The theory that slow and steady wins the race when it comes to weight loss has been debunked.

A new study has found that some crash diets can work and could, in fact, have greater lasting impacts when it comes to beating the bulge.

A trial, involving 200 medically obese people, examined the outcomes of both rapid and gradual weight loss.

It also looked at the speed at which kilos were shed, and the rate at which they were regained.

Mary Caruana, a self-proclaimed yo-yo dieter, was among the participants.

She was assigned to the rapid weight loss group and insisted the fast results motivated and encouraged her to stick at it.

"In the first week, I lost three-and-a-half kilos so after that it was just really easy," she told Seven News.

Mary dropped another one-and-a-half kilos each week, a kilo more, on average, than those in the gradual weight loss group.

She lost 15 kilos in total during the 12-week trial.

"Because you've lost it quickly, I think you're more inclined to work hard at keeping it off," she said.

While both groups regained the weight after the trial had finished, it was the group who took longer to shed the kilos who put it back on faster.

Professor Joseph Proietto, of the University of Melbourne, said: "As we know most people regain the weight that they lose, and it's always been said that 'the quicker you lose it, the quicker you regain it', but we've disproved that."

Researchers hope the current medical approach to weight loss will be reviewed.

"We think this is a significant finding and we hope that the guidelines will be changed," Prof Proietto said.

Those behind the study stress fad diets and rapid weight loss can be dangerous and they are not for everyone.

It is important to consult your doctor or health professional before radically altering your diet or lifestyle.