Dave: "It's sad, Norbert, no matter how much I diet, I'm not getting back my college physique!"

Norbert: "Was it even good then??"

Dave: "Hey, at least it was better! But seriously, while I've actually lost about thirty pounds recently, I worry about it creeping back."

Norbert: "Here's a study that may help..."

The new study, conducted at Boston Children's Hospital, explains that while calorie restriction is important, what we eat determines whether the weight stays off.

The study compared three popular diets for weight loss and weight maintenance: low-carb, low-fat, and low-glycemic diets.

A group of overweight adults between eighteen and forty years of age who had already lost ten percent of their body weight were placed on one of the three diets, but all ate the same number of calories.

At the end of ten weeks, people on the low-carb diet had the fastest metabolism, burned the most calories while at rest, and had the best total energy expenditure. But it also had negative effects, like high levels of the stress hormone cortisol, which can lead to diabetes. They also had high biochemical markers like CRP, which is associated with inflammation and heart disease.

The low-fat diet led to the lowest metabolism and produced the hormone leptin, which can stimulate hunger and cause weight gain.

In contrast, the low glycemic diet allowed stable blood sugar and metabolism levels without spikes in stress hormones and other negative biochemical markers.

A low glycemic diet uses fiber-right foods such as beans, fruits and vegetables, whole grains, lean meats, and healthy fats - from nuts, for example. What this study emphasizes is that food choice is crucial to maximizing your metabolism and keeping your weight off.

Remember, though - before you start a new diet plan, talk to your physician.