Protein power for dieters

THURSDAY, JUNE 29, 2006

Anyone wanting to shape up for summer should break out the eggs, chicken, fish, meat and protein supplements and pack away the pasta and potatoes.

Yet another study has confirmed that a protein-rich diet is more effective than a carbohydrate rich one for eliminating body fat and maintaining important lean tissue.

Researchers at the University of Illinois1 discovered a diet high in protein enhances the effectiveness of an exercise regime far better than the so called 'carbo-loading' typically favoured by those trying to get fitter.

In the study published in the Journal of Nutrition, the researchers found those who replaced complex carbohydrate foods such as pasta, rice and wholemeal bread with high-protein foods such as dairy products and meat lost more body fat and gained more muscle tone. When protein intake was doubled and carbohydrate intake halved, the subjects not only lost body fat and improved their lean tissue, but also showed a greater reduction in triglycerides (the bad guys for the heart) and a greater increase in HDL (the good guys for the heart).
"There's an interactive effect when a protein-rich diet is combined with exercise and the two work together to correct body composition," researcher Donald Layman said. "Dieters lose more weight and they lose fat, not muscle, which is important."

Professor Layman said a high-protein diet provided humans with high levels of the essential amino acid leucine. Together with insulin, leucine stimulates protein synthesis in muscles, which keeps them toned while allowing the body to burn fat.
Natasha Zamburro, Aussie Bodies nutritionist, is not surprised by these findings and adds to Professor Layman's comments. "For a number of years we have seen the benefit of higher protein intake on the body composition of women and men alike. While we encourage people to eat a wide variety of protein foods, we have found that benefits are particularly evident with people who use Whey Protein Concentrate -WPC (as in Perfect Protein) or Soy Protein Isolate (as in Perfect Soy Protein and Trim Pure Soy Protein)." According to Zamburro, "WPC and Soy Protein are particularly rich in Leucine and the other critical cluster amino acids which help tone muscles."

Professor Laymen recommended people trying to lose weight add dairy proteins, meat and eggs to their daily food intake while cutting down on carbohydrates, although not eliminating them completely. Zamburro agrees to a large extent, but cautions that "many people may be better off including easily digested WPC or soy protein supplements as well as other protein foods, to ensure a healthy digestive system and an adequate intake of Calcium, often missing in higher protein diets."