High-Fat, Low-Carb Diets Might Be Bad for the Heart

A short-term study followed 19 people for two weeks on the Atkins Diet with cardiac monitoring for heart metabolism and function. Energy storage in the heart was monitored using magnetic resonance spectroscopy (MRS) at the University of Oxford Center for Clinical Magnetic Resonance Research. Energy storage in the heart was found to be reduced on average by 16%. In some of the individuals the energy reduction was as much as 33%. Diastolic dysfunction (a stiffening of the heart muscle) was also detected. The changes were reversed within two weeks of returning to a normal diet.

The results of the study (lead researcher Kieran Clarke) were reported on November 13 2005 at American Heart Association Scientific Sessions 2005 in Dallas, Texas. Professor Kieran Clarke pointed out that the length of the study was short and that it was unknown if the heart would have corrected the low energy state given the chance to adapt. It was recognized that although severe energy depletion is a key feature of heart failure, the diet did not cause heart failure. The bottom line of this short study is that the diet did cause a direct effect on heart metabolism and that the low-carb, high-fat diet study provides initial insight that the effect may not be healthy for the heart.