Monday, June 9, 2008

....and More Low Carb Research

Amby Burfoot's blog at Runners' World often picks up some interesting research. Like this:

Low Carb, High Protein Diets Get High Marks, Especially In One Unique Child Study
A review of low carb, relatively high protein diets received high marks in a nutrition journal article. The article says that the low carb diets have generally produced more weight loss than higher carb diets, primarily because the protein seems to increase satiety (appetite satisfaction). A more startling weight-loss study among obese elementary school children showed that their total cholesterol and triglycerides dropped significantly when they were put on a low-carb but otherwise-all-you-can-eat diet.

She is actually pointing to these two studies:

The role of protein in weight management.

Several studies have shown that high protein meals and foods are more satiating than high carbohydrate or high fat meals when assessed by subjective ratings of satiety. Few of these studies were able to control for potentially confounding variables. Test meals differ widely in physical and sensory properties so it cannot be concluded that it is protein conferring these effects. When sensory properties are controlled up to 10-30% more calories are eaten at a subsequent meal with a high carbohydrate liquid meal than a high protein liquid meal with no difference in protein sources or BMI status. Weight loss studies examining the metabolic effects of isocaloric high protein energy restricted diets with high carbohydrate structured diets have not shown differences in kilojoule intake and weight loss despite expected satiety differences. Such studies do not allow the effects of increased satiety attributable to protein to be expressed as the dietary protocols have required all foods to be consumed. However, several longer term studies have noted improvements in body composition on a higher protein pattern despite similar weight loss. An interaction between protein intake and exercise on improved lean mass retention has also been observed. Studies comparing ad libitun high protein diets to high carbohydrate diets have usually shown greater weight loss on the high protein pattern and that enhanced satiety was the most important factor in the weight loss.


Unlimited energy, restricted carbohydrate diet improves lipid parameters in obese children.

BACKGROUND: Childhood obesity is a leading health concern. We have previously demonstrated the effectiveness of a restricted-carbohydrate, unlimited energy diet for weight reduction in elementary school-aged children. To our knowledge, there are no studies that have looked at the effect of this diet on lipid profiles in elementary school-aged children. Therefore, the objective of this pilot study was to examine the effect of a restricted-carbohydrate, unlimited protein, unlimited energy diet on lipid profiles in obese children 6 to 12 years of age. METHODS: Overweight children (body mass index >97%) referred to our obesity clinic were treated with a restricted-carbohydrate (<30 grams daily), unlimited protein, and unlimited energy diet. Weight, height, body mass index, and fasting lipid profiles were obtained at baseline and at 10 weeks on each patient. RESULTS: Twenty-seven patients were enrolled in our study, with a total of 18 patients returning for our 10 week follow-up (67%). The study group included 10 males and 8 females, with an age range of 6 to 12 years. Both total serum cholesterol and triglyceride levels showed a significant reduction; 24.2 (P = 0.018) and 56.9 (P = 0.015) mg/dL, respectively. CONCLUSIONS: We have demonstrated a significant decrease in total cholesterol and triglycerides in elementary school-aged children after 10 weeks of a restricted-carbohydrate, unlimited protein, and unlimited energy diet. We suggest that this diet may decrease cardiovascular risk factors in obese children. Long-term studies will be needed to substantiate these data.

1 comment:

Stephan said...

I like how they methodically avoid mentioning the kids are also eating more fat.