Researchers at the University of Melbourne have debunked the myth that gradual weight loss is more effective than rapid weight loss.
They found that slow and steady weight loss, recommended by current guidelines worldwide, does not reduce the amount or rate of weight regain among obese individuals as compared to those losing weight quickly.
For the study, the researchers randomly assigned 200 obese adults (BMI 30-45kg/m²) to either a 12-week Rapid Weight Loss (RWL) programme on a very-low-calorie diet (450-800 kcal/day) or a 36-week gradual weight-loss (GWL) programme. The GWL programme reduced participants' energy intake by approximately 500 kcal/day.
The researchers found that participants who lost weight faster were more likely to achieve target weight loss. Nearly 81 percent of participants in the RWL group lost ≥12.5 percent of their bodyweight as compared to just 50 percent in the GWL group.
"Across the world, guidelines recommend gradual weight loss for the treatment of obesity, reflecting the widely held belief that fast weight loss is more quickly regained. However, our results show that achieving a weight loss target of 12.5% is more likely, and drop-out is lower, if losing weight is done quickly," Katrina Purcell, dietician and the first author on the paper, said in a press release.
The researchers said that possible reasons behind RWL success can be attributed to low-calorie diets that promote greater satiety and less food intake by inducing ketosis. Shedding weight quickly may also encourage participants to continue with their diet and achieve better results.
"The study...indicates that for weight loss, a slow and steady approach does not win the race, and the myth that RAPID WEIGHT LOSS is associated with rapid weight regain is no more true than Aesop's fable. Clinicians should bear in mind that different weight loss approaches might be suitable for different patients in the management of clinical obesity, and that efforts to curb the speed of initial weight loss might hinder their ultimate weight loss success," said Dr Corby Martin and Professor Kishore Gadde from Pennington Biomedical Research Center.
The finding is published in The Lancet Diabetes & Endocrinology.
