Here comes another high protein vs high carboydrate diet study for weight loss...but first, a short story about why it interests me...
When I was in college, I remember going to a party at the home of four girls. While standing around in the kitchen, I realized they almost had as much cereal in their house as the local convenience store.
When I askeD them about it, they said they often eat cereal for all three meals of the day because they thought a high carbohydrate diet was good for fat loss. Yet three out of the four girls struggled with body fat.
Unfortunately, they bought into the popular notion promoted by dieticians in the 1990's that we all need to eat high-carbohydrate diets for fat loss. However, every year more and more research (not to mention experience) shows this to be untrue.
The latest study, from the journal, Nutrition and Metabolism, compared a moderate carbohydrate, moderate protein diet against a high carbohydrate diet for weight loss and choleseterol levels.
Nutr Metab (Lond). 2008 Nov 7;5(1):30. Moderate carbohydrate, moderate protein weight loss diet reduces cardiovascular disease risk compared to high carbohydrate, low protein diet in obese adults: A randomized clinical trial. Walker Lasker DA, Evans EM, Layman DK.
Fifty overweight adults ate a diet that was 500 calories lower than they needed to maintain their weight, and were put into one of two groups for this 4 month weight loss study.
The moderate carbohydrate, moderate protein group ate 1.6 grams of protein per kilogram of bodyweight (approximately 112 grams of protein for a 154 pound person) and less than 170 grams of carbohydrate per day.
The high- carbohydrate group ate only 0.8 grams of protein per kilogram of bodyweight (56 grams of protein for a 154 pound person) and less than 220 grams of carbohydrate per day.
At the end of four months, the higher protein diet group lost more body fat (8.7% vs. 5.7%) than the high carbohydrate group, and the higher protein group had greater reductions in triglycerides (a 34% decrease compared to a 14% decrease) and greater improvements in the good HDL cholesterol (a 5% increase compared to a 3% decrease).
This study shows that you don't need to make radical changes in your protein intake to get more fat loss and better blood lipid levels. Simply cut out 2 slices of bread and substitute two 20 gram protein shakes in your diet each day, and you'll lose more body fat.
Craig Ballantyne, CSCS, MS