The Diet Rollercoaster Explained


Don’t think your diet failed due to poor self-control – your body may be quietly undermining your weight-loss efforts.

When you lose weight, your appetite comes roaring back with a vengeance, concludes a new study appearing in the journal Obesity.

Flickr Image Courtesy: show and tell, CC BY-SA 2.0

The study followed 153 patients for a year and monitored how their bodies reacted to gradual weight loss. The researchers treated the patients with a drug called canagliflozin, which is “a sodium glucose co-transporter inhibitor” that can cause weight loss without the patients being directly aware of it.

Assessing how patients responded to the “secret” diet, the researchers witnessed “a proportional increase in appetite” for every kilogram of weight lost.

Specifically, the researchers discovered that appetite increased by about 100 calories per day for each kilogram that a patient lost.

The study results add weight to the growing body of evidence showing that individuals face an arduous task in keeping off extra pounds because the body takes active measures to resist it.

But while those studies largely focus on a person’s rate of metabolism before and after weight loss, the study shows that keeping off weight is even harder than previously thought.

The few individuals who successfully maintain weight loss over the long term do so by heroic and vigilant efforts to maintain behavior changes in the face of increased appetite along with persistent suppression of energy expenditure,” the study’s authors said.

“Our results provide the first quantification of the energy intake feedback control system in free-living humans,” reported the study’s authors.

While previous studies have reported on the snapback mechanism of off-again, on-again body weight, the study of canagliflozin adds an important control that other studies had not included.

Patients who received canagliflozin consumed approximately 100 more calories per day for each kilogram of weight they had lost, as opposed to patients in a control group who did not take the medication.

In the absence of ongoing efforts to restrain food intake following weight loss, feedback control of energy intake will result in eating above baseline levels with an accompanying acceleration of weight regain,” researchers concluded.

The researchers suggest that patients seeking to lose weight – and keep it off – should invest in lifestyle changes they can maintain due to the uphill battle they face.

Even diligently tracking one’s diet, such as keeping a log of food intake, has its flaws because individuals routinely misidentify the total amount of food they consume. In fact, the researchers describe dieters as, “…notorious for being unable to provide accurate estimates” of how much they eat every day.

“Self-reported measurements of energy intake may more accurately reflect the perceived effort of the dieter to adhere to the intervention rather than their actual energy intake,” they added.

That’s not to say you shouldn’t try. Dr. Kevin Hall, one of the study’s authors, has also developed a body weight planner, intended to help balance a person’s food intake and activity level. For people on a diet, they may be comforted to know that weight-loss goals are indeed as hard as they seem.