Macro partitioning
Low Glycemic Load (LG) diets result in a higher percentage of weight loss as fat and less loss of fat-free mass (FFM) compared to High Glycemic Load (HG) diets during caloric restriction, provided the individual loses more than 5% of body weight.
If you are dieting to lose weight, choosing a Lower Glycemic Load diet (moderate carbs, higher protein/fat) helps you lose more fat and keep more muscle than a High Glycemic Load diet, as long as you actually stick to the diet and lose a meaningful amount of weight (over 5%). However, this diet type does not prevent your metabolism from slowing down during weight loss. Focus on adherence; if you lose weight, the LG approach protects your muscle mass better.
However, in subjects who lost >5% body weight (n=26), the LG diet group had a higher percentage of weight loss as fat than the HG group (p<0.05)... This difference in percentage of weight loss as fat approached significance (P=0.063) at 6 months when all subjects were included in the analysis... the LG group had a significantly higher percentage of weight loss as fat (98.5 vs 87.4) and a significantly lower percentage of weight loss as FFM (1.50 vs 12.6; P= 0.047)
Why this rating
Randomized controlled trial with provided food (high adherence control), but small sample size (N=29) and the effect was only significant in a subset analysis.
Source
Long - Term Effects of Energy-Restricted Diets Differing in Glycemic Load on Metabolic Adaptation and Body Composition*
Sai Krupa Das et al. · The Open Nutrition Journal · 2008
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