When we talk about weight loss, most of us will think about having to diet. Today we can see the diet advertisements and suggestions appear everywhere. We have been taught to eat this and not that. We continually move from one diet to the other. We keep on losing weight and gaining it back within a few months, but what is the truth?

Dr. Arya Sharma, who is the chair of obesity research and management at the University of Alberta and is the medical director of the Weight Wise program at Edmonton’s Royal Alexandra Hospital, is not a fan of most diets.
"The minute you go on a diet, the minute you start losing weight the first thing that happens is your body says, 'OK we're going to shut down the furnace, there's not enough fuel coming in, we're not going to be shifting to fourth gear anymore,' and it happens automatically," he said.
Once the body gets used to a diet it adjusts and weight loss stops, leading to frustration on the part of the dieter. Inevitably most people will go back to their old eating habits, but with the body's metabolism slowed down, they gain even more weight than before. "And that's your yoyo effect," he said.

Dr. Arya Sharma is equally reticent on exercise as a means of weight loss. "There's a million benefits of exercise. It does everything including improving depression, preventing cancer; it'll do a million things for you. The one thing it does not do is help you lose weight." He points to a recent study, reported in the Journal of the American Medical Association, which followed 3,554 men and women over 20 years. Half the group exercised vigorously, the others led more sedentary lifestyles. Both groups gained weight, but the average difference was only 2.6 kilograms for men and 6.1 kilograms for women - after two decades. "So much for exercising to prevent weight gain," said Sharma.

A 2010 study at the Mayo Clinic found that those who exercise daily often gain weight because their bodies crave calories to make up for the energy used during exercise. Researcher Susan Jebb says most people don’t realize how much exercise is required to lose weight. “To burn off an extra 500 calories is typically an extra two hours of cycling...about two doughnuts.” When it comes to preventing Type II Diabetes, having a normal BMI is far more important than being aerobically fit.

“Studies have demonstrated no or modest weight loss with exercise alone...an exercise regimen is unlikely to result in short-term weight loss beyond what is achieved with dietary change.”

–SOURCE: The Mayo Clinic

"Unfortunately, diet and exercise have not proven effective strategies for weight loss, which has prompted the explosion in bariatric surgery."

SOURCE: Journal of the American College of Surgeons, June 2009.

"In general, for weight loss, exercise is pretty useless."

-Eric Ravussin, chair in diabetes and metabolism at Louisiana State University and a prominent exercise researcher.

"The only permanent treatment of severe or morbid obesity is bariatric surgery."

SOURCE: © 2009 Canadian Medical Association