September 2011
Excerpt from a Study in the Journal of Nutrition
New research suggests a higher-protein, lower-carbohydrate diet has a positive impact on body composition, trimming belly fat and increasing lean muscle, particularly when the proteins come from dairy products.
The study published in this month's issue of The Journal of Nutrition compared three groups of overweight and obese, but otherwise healthy, premenopausal women. Each consumed either low, medium or high amounts of dairy foods coupled with higher or lower amounts of protein and carbohydrates.
The women exercised seven days per week for four months, a routine that included five days of aerobic exercise and two days of circuit weightlifting.
According to the researchers, there were identical total weight losses among the groups, but the higher-protein, high-dairy group experienced greater whole-body fat and abdomen fat losses, greater lean mass gains and greater increases in strength.
All the tissue the women lost was fat, which has profound implications for longer-term health, say the researchers.
“One hundred per cent of the weight lost in the higher-protein, high-dairy group was fat. And the participants gained muscle mass, which is a major change in body composition,” said Andrea Josse, lead author of the study. “The preservation or even gain of muscle is very important for maintaining metabolic rate and preventing weight regain, which can be a major problem for many seeking to lose weight.”
Researchers found the lower-protein, low-dairy group lost about a pound and half of muscle, while the lower-protein, medium dairy group lost almost no muscle. In marked contrast, the higher-protein, high-dairy group actually gained a pound and half of muscle, representing a three-pound difference between the low- and high-dairy groups.