Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

BACKGROUND: High-fat, low-carbohydrate diets are widely used for weight reduction, but they may also have detrimental effects via increased circulating free fatty acid concentrations. OBJECTIVE: We tested whether raising plasma free fatty acids by using a high-fat, low-carbohydrate diet results in alterations in heart and brain in healthy subjects. DESIGN: Men (n = 16) aged 22 ± 1 y (mean ± SE) were randomly assigned to 5 d of a high-fat, low-carbohydrate diet containing 75 ± 1% of calorie intake through fat consumption or to an isocaloric standard diet providing 23 ± 1% of calorie intake as fat. In a crossover design, subjects undertook the alternate diet after a 2-wk washout period, with results compared after the diet periods. Cardiac (31)P magnetic resonance (MR) spectroscopy and MR imaging, echocardiography, and computerized cognitive tests were used to assess cardiac phosphocreatine (PCr)/ATP, cardiac function, and cognitive function, respectively. RESULTS: Compared with the standard diet, subjects who consumed the high-fat, low-carbohydrate diet had 44% higher plasma free fatty acids (P < 0.05), 9% lower cardiac PCr/ATP (P < 0.01), and no change in cardiac function. Cognitive tests showed impaired attention (P < 0.01), speed (P < 0.001), and mood (P < 0.01) after the high-fat, low-carbohydrate diet. CONCLUSION: Raising plasma free fatty acids decreased myocardial PCr/ATP and reduced cognition, which suggests that a high-fat diet is detrimental to heart and brain in healthy subjects.

Original publication

DOI

10.3945/ajcn.110.002758

Type

Journal article

Journal

Am J Clin Nutr

Publication Date

04/2011

Volume

93

Pages

748 - 755

Keywords

Adenosine Triphosphate, Adult, Affect, Attention, Cognition, Cross-Over Studies, Diet, Carbohydrate-Restricted, Dietary Carbohydrates, Dietary Fats, Echocardiography, Energy Intake, Energy Metabolism, Fatty Acids, Nonesterified, Heart, Humans, Magnetic Resonance Imaging, Magnetic Resonance Spectroscopy, Male, Phosphocreatine, Reference Values, Young Adult