While doctors may prescribe diet and exercise as a remedy for obesity, a new Australian study shows that regaining weight may be inevitable due to forces outside people’s control: hormones. The new findings came to light after tracking 50 overweight or obese adults on a low-calorie diet over a 10-week period, Australian researchers found that once participants lost weight, hormone levels — particularly those that influence hunger — shifted in the body, leading to increased appetites and weight regain.
The study involved 50 adults with a body mass index (BMI) or between 27 and 40, averaging 95 kg (209 lbs). After an initial loss of about 13 kg (29 lbs) scientists at the University of Melbourne found that the levels of appetite-regulating hormones changed, resulting in a regain of about 5 kg over the course of a year.
The new findings, published in The New England Journal of Medicine last week, throws a wrench in the conventional message that diet and exercise alone are enough to maintain a healthy weight and reveals the important role hormones play in regulating body weight, pointed study co-author Joseph Proietto.
“The weight relapse has a strong physiological basis and is not simply the result of the voluntary resumption of old habits,” he said in a statement. To pre-empt the onset of obesity, Proietto suggests it would be more effective to start young and focus public health efforts towards children.
“The study also suggests that hunger following weight loss needs to be addressed. This may be possible with long-term pharmacotherapy or hormone manipulation but these options need to be investigated,” he said.
The results of the Australian study corroborate findings in another paper released earlier this year, in which researchers from Spain confirmed that people with high levels of the hormone leptin and low levels of ghrelin are more likely to gain the weight they lost.
The study showed that diet and exercise are not enough to maintain a healthy weight.
Hormones play a very important role in regulating body weight.
The reason most people gain weight on a relapse after a diet are hormonal.