A Norwegian study presented at the European Congress on obesity is questioning the long-standing belief that losing weight too quickly is unhealthy and inevitably leads to weight regain.
To compare the effectiveness of rapid versus gradual weight loss, researchers followed 284 adults with obesity, 90 per cent of them women. They were assigned to either a rapid or gradual weight-loss programme.
During the first 16 weeks, the rapid weight-loss group followed a low-calorie diet that started at fewer than 1,000 calories per day and gradually increased to about 1,500 calories daily. Meanwhile, the gradual weight-loss group reduced their calorie intake more moderately, consuming an average of around 1,400 calories per day.
The participants in both groups then took part in the same 36-week maintenance programme aimed at preventing weight regain. They received support through regular group meetings and virtual or phone check-ins. They were encouraged to focus on nutritious foods such as fruits, vegetables, whole grains, lean proteins, and low-fat dairy products, while cutting back on foods high in saturated fat and added sugar.
Those in the rapid weight-loss group lost an average of 12.9 per cent of their body weight during the first 16 weeks, compared with just 8.1 per cent in the gradual group.
After one year, the rapid weight-loss group continued to maintain greater overall weight loss, averaging 14.4 per cent compared with 10.5 per cent in the gradual group. They were also more likely to reach healthy BMI and waist-size targets associated with a lower risk of conditions such as type 2 diabetes, high blood pressure, heart disease, and osteoarthritis.
“Our results clearly challenge the prevailing belief that slow and steady gradual weight loss is necessary to prevent weight regain and reduce obesity-related complications,” the lead researcher concluded.
