Irizarry KA, et al. - In children with Prader-Willi syndrome (PWS), researchers evaluated the hormonal and metabolic consequences of carbohydrate restriction. They compared fasting and postprandial concentrations of hormones and metabolites in 8 PWS children (age 9-18 years) fed randomly on low carbohydrate, high-fat (LC, 15% carb; 65% fat; 20% protein) and low-fat, high carbohydrate (LF, 65% carb, 15% fat, 20% protein) diets matched for calories and protein. During first hospital admission, participants were randomized to eat either the LC or LF diet and the second diet during a subsequent admission. After overnight fasting and 1 hour after a mixed meal, blood samples were collected. According to findings, GLP-1 increases with low carbohydrate feeding and decreases in the ghrelin to GLP-1 ratio could limit food intake and improve glycaemic control in PWS. Other potential benefits of restricting carbohydrates may include mobilizing and oxidizing fat and reducing the insulin resistance marker TG/HDL ratio. Long-term studies of low carbohydrate efficacy and safety, however, require increases in CRP, AST and ALT.