The best diet plan for maintaining weight loss is one that is high in protein and low in glycemic index (a measure of how quickly a food will raise your blood sugar). So concludes the largest diet study to date, conducted by researchers from the University of Copenhagen.
Over a thousand adults began the study by following an 8 week low-calorie diet, during which they lost an average of 11 kg (just over 24 lbs). The 773 participants who made it all the way through that initial phase were divided into five maintenance groups, consuming:
- A low-protein diet (13% of energy consumed) with a high glycemic index (GI)
- A low-protein, low GI diet
- A high-protein (25% of energy consumed), low GI diet
- A high-protein, high GI diet
- A control group that followed the current dietary recommendations without special instructions regarding glycemic index levels
548 of these subjects lasted for the entire six month period of this second phase. Along the way, the volunteers received nutritional guidance and supplied periodic blood and urine samples.
Participants in the low protein, high GI group regained the most weight, 1.67 kg on average. In contrast, people using the high protein and/or low GI diets regained considerably less weight, with the most benefit going to those who used both.
827 children of participants also followed these five diet plans (they did not undergo the eight week calorie restriction phase of the study). Among the kids eating a high protein, low GI diet along with their parents, the obesity rate dropped from 46% to 39%.You can find a chart of the glycemic index of many common foods here.