Short-term consumption of a high-fat diet impairs whole-body efficiency and cognitive function in sedentary men.
We recently showed that a short-term high-fat diet blunted exercise performance in rats, accompanied by increased uncoupling protein levels and greater respiratory uncoupling. In this study, we investigated the effects of a similar diet on physical and cognitive performance in humans. Twenty sedentary men were assessed when consuming a standardized, nutritionally balanced diet (control) and after 7 d of consuming a diet comprising 74% kcal from fat. Efficiency was measured during a standardized exercise task, and cognition was assessed using a computerized assessment battery. Skeletal muscle mitochondrial function was measured using (31)P magnetic resonance spectroscopy. The diet increased mean ± se plasma free fatty acids by 44% (0.32±0.03 vs. 0.46±0.05 mM; P<0.05) and decreased whole-body efficiency by 3% (21±1 vs. 18±1%; P<0.05), although muscle uncoupling protein (UCP3) content and maximal mitochondrial function were unchanged. High-fat diet consumption also increased subjects' simple reaction times (P<0.01) and decreased power of attention (P<0.01). Thus, we have shown that a high-fat diet blunts whole-body efficiency and cognition in sedentary men. We suggest that this effect may be due to increased respiratory uncoupling.
Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, UK. l.m.edwards@utas.edu.au
Lindsay M
LM
Edwards
Andrew J
AJ
Murray
Cameron J
CJ
Holloway
Emma E
EE
Carter
Graham J
GJ
Kemp
Ion
I
Codreanu
Helen
H
Brooker
Damian J
DJ
Tyler
Peter A
PA
Robbins
Kieran
K
Clarke
D000328:Adult; D003071:Cognition / Q000502:physiology*; D004041:Dietary Fats / Q000009:adverse effects* / Q000493:pharmacokinetics; D004734:Energy Metabolism / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D006801:Humans; D007473:Ion Channels / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D008928:Mitochondria / Q000378:metabolism*; D024101:Mitochondrial Proteins / Q000378:metabolism; D008954:Models, Biological; D009124:Muscle Proteins / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism; D010101:Oxygen Consumption / Q000502:physiology; D010758:Phosphorus / Q000378:metabolism; D057185:Sedentary Behavior; D000071247:Uncoupling Protein 3
D004041:Dietary Fats; D007473:Ion Channels; D024101:Mitochondrial Proteins; D009124:Muscle Proteins; C000604392:UCP3 protein, human; C000604394:Ucp3 protein, rat; D000071247:Uncoupling Protein 3; D010758:Phosphorus