A LEADING GROUP of obesity experts have questioned the belief that eating less and moving more is sufficient to treat obesity.
They argue, in a paper published today in The Lancet Diabetes & Endrocrinology, that it is a chronic disease with largely biological causes that cannot be cured with dieting and exercise alone.
Many people with obesity can lose weight for a few months through changing their diets and getting more exercise but research shows 80% to 95% regain their lost weight eventually. One explanation for this limited success, according to these experts, is that reducing the intake of calories can trigger several biological systems that humans have.
These systems evolved when humans needed to survive times of food scarcity but in modern humans, who have had obesity for some time, these adaptations encourage calorie consumption and the storage of fat to protect the person’s highest sustained weight.
Overriding this fat-loss defence does not appear to be possible for most people through just lifestyle changes, the authors say.
“Although lifestyle modifications may result in lasting weight loss in individuals who are overweight, in those with chronic obesity, bodyweight seems to become biologically ‘stamped in’ and defended”, explains Dr Christopher Ochner, lead author and Assistant Professor of Pediatrics and Psychiatry at the Icahn School of Medicine at Mount Sinai in New York, USA.
Therefore, the current advice to eat less and exercise more may be no more effective for most individuals with obesity than a recommendation to avoid sharp objects for someone bleeding profusely.
“Few individuals ever truly recover from obesity; rather they suffer from ‘obesity in remission’. They are biologically very different from individuals of the same age, sex, and bodyweight who never had obesity,” he explained.
Biological factors have to be addressed if it is to be overcome, according to these experts. To date, only the Roux-en-Y gastric bypass surgery has been shown to reverse obesity-induced changes in appetite hormones and the brain’s response to food. This, say the authors, might explain why weight loss surgery is the only treatment showing long-term effectiveness in individuals with sustained obesity.
Their suggestion is that obesity should be recognised as a chronic disease that requires biological interventions such as physiotherapy or surgery as well as lifestyle changes.