TY - JOUR
T1 - A ketogenic diet lowers myocardial fatty acid oxidation but does not affect oxygen consumption
T2 - a study in overweight humans
AU - Luong, Thien Vinh
AU - Pedersen, Mette Glavind Bülow
AU - Abild, Caroline Bruun
AU - Cunnane, Stephen C
AU - Croteau, Etienne
AU - Lauritsen, Katrine Meyer
AU - Kjaerulff, Mette Louise Gram
AU - Tolbod, Lars Poulsen
AU - Møller, Niels
AU - Søndergaard, Esben
AU - Gormsen, Lars Christian
N1 - © 2024 The Authors. Obesity published by Wiley Periodicals LLC on behalf of The Obesity Society.
PY - 2024/3
Y1 - 2024/3
N2 - OBJECTIVE: A ketogenic diet (KD) characterized by very low carbohydrate intake and high fat consumption may simultaneously induce weight loss and be cardioprotective. The "thrifty substrate hypothesis" posits that ketone bodies are more energy efficient compared with other cardiac oxidative substrates such as fatty acids. This work aimed to study whether a KD with presumed increased myocardial ketone body utilization reduces cardiac fatty acid uptake and oxidation, resulting in decreased myocardial oxygen consumption (MVO 2 ). METHODS: This randomized controlled crossover trial examined 11 individuals with overweight or obesity on two occasions: (1) after a KD and (2) after a standard diet. Myocardial free fatty acid (FFA) oxidation, uptake, and esterification rate were measured using dynamic [ 11 C]palmitate positron emission tomography (PET)/computed tomography, whereas MVO 2 and myocardial external efficiency (MEE) were measured using dynamic [ 11 C]acetate PET. RESULTS: The KD increased plasma β-hydroxybutyrate, reduced myocardial FFA oxidation (p < 0.01) and uptake (p = 0.03), and increased FFA esterification (p = 0.03). No changes were observed in MVO 2 (p = 0.2) or MEE (p = 0.87). CONCLUSIONS: A KD significantly reduced myocardial FFA uptake and oxidation, presumably by increasing ketone body oxidation. However, this change in cardiac substrate utilization did not improve MVO 2 , speaking against the thrifty substrate hypothesis.
AB - OBJECTIVE: A ketogenic diet (KD) characterized by very low carbohydrate intake and high fat consumption may simultaneously induce weight loss and be cardioprotective. The "thrifty substrate hypothesis" posits that ketone bodies are more energy efficient compared with other cardiac oxidative substrates such as fatty acids. This work aimed to study whether a KD with presumed increased myocardial ketone body utilization reduces cardiac fatty acid uptake and oxidation, resulting in decreased myocardial oxygen consumption (MVO 2 ). METHODS: This randomized controlled crossover trial examined 11 individuals with overweight or obesity on two occasions: (1) after a KD and (2) after a standard diet. Myocardial free fatty acid (FFA) oxidation, uptake, and esterification rate were measured using dynamic [ 11 C]palmitate positron emission tomography (PET)/computed tomography, whereas MVO 2 and myocardial external efficiency (MEE) were measured using dynamic [ 11 C]acetate PET. RESULTS: The KD increased plasma β-hydroxybutyrate, reduced myocardial FFA oxidation (p < 0.01) and uptake (p = 0.03), and increased FFA esterification (p = 0.03). No changes were observed in MVO 2 (p = 0.2) or MEE (p = 0.87). CONCLUSIONS: A KD significantly reduced myocardial FFA uptake and oxidation, presumably by increasing ketone body oxidation. However, this change in cardiac substrate utilization did not improve MVO 2 , speaking against the thrifty substrate hypothesis.
KW - Cross-Over Studies
KW - Diet, Ketogenic
KW - Fatty Acids, Nonesterified/metabolism
KW - Fatty Acids/metabolism
KW - Humans
KW - Ketone Bodies/metabolism
KW - Myocardium/metabolism
KW - Overweight/metabolism
KW - Oxygen Consumption
U2 - 10.1002/oby.23967
DO - 10.1002/oby.23967
M3 - Journal article
C2 - 38258448
SN - 1930-7381
VL - 32
SP - 506
EP - 516
JO - Obesity
JF - Obesity
IS - 3
ER -