Friday, April 11, 2014
As a regular reader, you may remember the DIOGENES trial, which studied the impact of different levels of protein intake on sustaining a weight-loss induced by eight weeks of a low-calorie formula diet (800 Kcal resulting in an average weight loss of about 11 Kg).
The original paper showed that individuals on a high-protein diet (providing 12 % more energy from protein that the low-protein diet) were about half as likely to discontinue the 26 week trial than those on a low-protein intake.
Now, a new paper from DIOGENES, published in the International Journal of Obesity, reports on the weight outcomes in participants, who were followed for up to 12 months in two of the participating centres (n=256).
The five ad libitum diets (no caloric restrictions) that followed the low-calorie diet (resulting in an average weight loss of about 11 Kg) were:
1) a low-protein and low-glycemic index diet,
2) a low-protein and high-glycemic-index diet,
3) a high-protein and low-glycemic-index diet,
4) a high-protein and high-glycemic-index diet,
5) a control diet.
While average weight regain over the 12-months was about 4 Kg (of the 11 Kg lost initially), the subjects on the high-protein diets kept off almost twice as much weight as those on the low-protien diets (glycemic index did not appear to make any significant difference).
Thus, the authors conclude that following a higher-protein ad libitum diet improves weight loss maintenance in overweight and obese adults over 12 months.
Clinicians may wish to stress the importance of maintaining a high-normal protein intake to clients trying to avoid regaining pounds that they have lost.