LOSING a lot of weight all at once is the best way to permanently slim down according to the latest studies, which go against commonly held dietary beliefs and accepted wisdom even among doctors.

Katrina Purcell of the University of Melbourne in Australia presented a study at Stockholm’s International Congress on Obesity in which she compared a rapid diet to lose around 1.5 kilos (three pounds) a week over 12 weeks, to a gradual 36-week diet to lose 0.5 kilos per week.

“Surprisingly, and against current beliefs, this study shows rapid weight loss appears to be superior to gradual weight loss in achieving target weight,” she said of the study conducted on subjects weighing around 100 kilos.

Her results showed that 78 percent of those on the rapid diet achieved the target of losing 15 percent of their body weight within the determined period, while only 48 percent of those on the gradual diet met the target.

One of the reasons, she said, had to do with motivation.

“On the rapid diet subjects lose 1.5kg a week and that keeps them going. On the gradual diet, when you lose 0.5 kg ‘now and then’ motivation is harder to keep, “she said.

Four of the participants following the gradual diet gave up before the end of the experiment against only one in the rapid diet group.

Purcell is, however, quick to warn against so-called crash diets, in which weight is lost very quickly by drastically slashing calories.

“Don’t do it by yourself, do it with a dietician,” she said.

But her study carried a heavy handicap: it does not say what happened to participants after the initial weight loss, with many doctors and dieticians believing that more weight loss is related to more weight gain thereafter,

That is why the researcher is following the two groups to see who of the rapid or gradual dieters better keeps the weight off. Those results are expected in about three years.

And despite her findings, Purcell continues to advocate long-term diets because they imply a life-long change in eating habits.

In fact, researchers agree that eating and lifestyle habits are among the main culprits contributing to obesity.

At the congress, experts advocated controlling portion sizes, fighting against aggressive marketing from the food industry, product reformulation to lower salt and sugar contents, and labeling menus for calorie content.