Galactose promotes fat mobilization in obese lactating and non‐lactating women

Abstract

BackgroundGalactose consumption results in a lower rise in plasma glucose and insulin concentrations when compared to glucose. The lower insulin might promote lipolysis during meal absorption.HypothesisAn isocaloric galactose drink, when compared to glucose, will sustain fat mobilization during meal consumption while not adversely affecting milk production.Subjects5 healthy, obese (BMI 34.4±2.4), exclusively breastfeeding and 5 non‐lactating (BMI 36.3±1.3) women were studied in a crossover, randomized, single blinded design. During 2d on both occasions, subjects received drinks providing 70% of the daily resting energy requirement (RMR) of which glucose or galactose provided 55% of RMR. Primary outcome variables were: rates of appearance (Ra) of glycerol, glucose and palmitate, milk production, substrate and hormone concentrations, energy expenditure and substrate oxidation.ResultsIn all subjects, during galactose, as compared to glucose feeding, plasma glucose, insulin and C‐peptide were lower (p<0.05) while FFA and glycerol were higher (p<0.01). Glucose Ra was 72% lower and glycerol and palmitate Ra were 39 and 53 % higher (p<0.01) during galactose consumption. Glycerol Ra ( μmol·kg−1·min−1) was higher during galactose than glucose feeding in both control (2.0±0.3 vs. 1.4±0.2, p<0.05) and lactating women (2.2±0.4 vs. 1.7±0.3, p<0.01). Milk production, energy expenditure and substrate oxidation were similar between the two sugars.ConclusionsConsumption of galactose sustains fat mobilization during meal absorption. Thus; galactose might facilitate body fat loss in obese women. RO1DK 55478, HD 37857, MO1‐RR‐00188‐34.