Effect of Long-Term High-Carbohydrate Low-Fat Intake on Substrate Utilization andPlasma Lipoprotein Concentrations in Postmenopausal Women

摘要

The objective of this study was to determine if changes in plasma lipoproteinconcentrations that occur in response to high-carbohydrate, low-fat (HCLF) intake may be associated with or result from changes in substrate utilization. By implementing three diets which replaced energy from fat with carbohydrate, stepwise, over a 16-week period, we assessed the metabolic effects of a controlled increase in carbohydrate consumption in postmenopausal women. Substrate utilization was assessed by analysis of plasma metabolites (e.g. lactate, free glycerol (FO), and free fatty acids (FFA)) as well as respiratory quotient (RQ) measurements at baseline and three different timepoints throughout the study. Fasting insulin and glucose concentrations were measured to assess insulin sensitivity. Following the increase in carbohydrate consumption, mean fasting insulin concentration decreased nearly 24% and was accompanied by a concurrent drop in fasting glucose levels. Fasting RQ measurements, plasma FFA and FG concentrations following intervention did not significantly shift from