Energy metabolism and the metabolic syndrome: does a lower basal metabolic rate signal recovery following weight loss?
OBJECTIVE
To determine whether basal metabolic rate (BMR) was causally related to MetS, and to study the role of gender in this relationship.


METHODS
Seventy-two Caucasian subjects (43 women, 29 men) had changes in basal metabolic rate (BMR), carbohydrate oxidation rate (COR), fat oxidation rate (FOR) and prevalence of the metabolic syndrome (MetS) assessed in response to weight loss.


RESULTS
There was a significant gender×MetS interaction in BMR at the start. Women with MetS had higher adjusted BMR, whilst men with MetS had lower adjusted BMR than their respective counterparts. Weight loss resulted in a significant decrease in fat mass (-5.2±0.31 kg, p=0.001), fat free mass (-2.3±0.27 kg, p=0.001), BMR (-549±58 kJ/d, p=0.001) and a decreased proportion of MetS (22/72, χ(2)=0.005). Subjects who recovered from MetS after weight loss (RMS) had ∼250 kJ/d significantly lower adjusted BMR compared to those who were never MetS (NMS, p=0.046) and those who still had MetS (MetS+, p=0.047). Regression analysis showed that change (Δ) in BMR was best determined by Δglucose×gender interaction (r(2)=23%), ΔFOR (r(2)=20.3%), ΔCOR (r(2)=19.4%) and Δtriglycerides (r(2)=7.8%).


CONCLUSIONS
There is a sexual dimorphism of BMR in MetS. Overall, the data support the notion that alterations in BMR may be central to the etiopathogenesis of MetS.
Program of Nutrition, School of Public Health, Curtin Health Innovation Research Institute, Curtin University, Perth 6845, Western Australia, Australia. m.soares@curtin.edu.au
Mario J
MJ
Soares
Nicola K
NK
Cummings
Wendy L Chan She
WL
Ping-Delfos
D001481:Basal Metabolism / Q000502:physiology*; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000175:diagnosis / Q000453:epidemiology / Q000378:metabolism* / Q000503:physiopathology; D008875:Middle Aged; D020127:Recovery of Function / Q000502:physiology*; D015431:Weight Loss / Q000502:physiology*