In a new long-term diet study where magnetic resonance imaging (MRI) imaging technology was used for the first time scientists found low-carbohydrate diets to be superior to low-fat diets.
“Weighing patients or using blood tests to detect changes, hasn’t, until now, given us accurate pictures, literally, of how different fat deposits are impacted disproportionately by diet and exercise,” says lead researcher Iris Shai.
The findings in the study suggest that moderate exercise combined with a Mediterranean/low carb diet may help reduce the amount of some fat deposits even if a person does not lose significant weight as part of the effort. A mediterranean/low carb diet is high in unsaturated fats and low in carbohydrates.
The new study, published in the American Heart Association journal, Circulation, used MRI imaging technology for the first time to plot the diverse changes in an array of body organ fat storage pools during 18 months of the Mediterranean/low-carbohydrate and low-fat diets, with and without moderate physical exercise.
“We learned in this trial that moderate, but persistent, weight loss may have dramatic beneficial effects on fat deposits related to diabetes and cardiovascular diseases,” says Shai.
The study suggests a Mediterranean diet is a more effective strategy than a low-fat diet to reverse morbid fat storage. The results in the study showed that the best strategy for reducing fat deposits around the liver (-29%), the abdomen (-22%) and the heart (-11%) was to combine moderate exercise with a Mediterranean diet, even if weigh loss may not be significant.
“Our study demonstrates that improving nutritional quality and being physically active can improve cardio-metabolic risk markers through changes in visceral/ectopic fat deposits that are not reflected by changes in body weight alone.”
The 18-month trial included 278 sedentary adults in an isolated workplace, the Nuclear Research Center, with a monitored lunch provided. The participants were either following a low-fat diet or Mediterranean/low-carbohydrate diet with or without an exercise programme.
MRI scans were taken at six and 18 months during the randomized, controlled trial which was conducted by the Ben-Gurion University of the Negev in collaboration with the Dimona Nuclear Research Center and Soroka University Medical Center in Israel, as well as Harvard University and Leipzig University in Germany.