People who cut out carbohydrates as part of a diet may be reducing their brainpower as well as their waistline according to a study by researchers at Tufts University in the U.S. The study compared nine women on a low-carbohydrate, Atkins-style diet and ten women following a low-calorie diet based on advice from the American Dietetic Association. The dieters completed five testing sessions which assessed attention, long-term memory, short-term memory, visual attention and spatial memory. The low-carb dieters showed a gradual decrease in performance on the memory-related tasks compared to the low-calorie dieters. Their reaction times were slower and their visual-spatial memory worse. However, the low-carb dieters did do better than the low-calorie ones on the attention task; perhaps because fat and protein, which tend to be consumed more on these kind of diets, can improve people's attention in the short term.
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