LOW CARB DIET BETTER FOR WEIGHT LOSS AND HELPS YOUR BRAIN WORK FASTER THAN LOW FAT DIET
In a recent eight week trial comparing a low carb high fat diet (LCHF) with a conventional high carb low fat (HCLF) weight loss diet, researchers investigated which diet was more effective for weight loss, improvement of mood and cognitive functions such as speed of processing and working memory in 93 overweight or obese adults. They found that the people on the low carb diet lost more weight than those on the low fat diet and also had better 'speed of processing' in tests, meaning essentially that their brains worked faster! Both groups had improvements in mood which may be simply due to feeling better about themselves because they were losing weight and neither group had an improvement in their memory.

Title: Low- and high-carbohydrate weight-loss diets have similar effects on mood but not cognitive performance, Halyburton AK et al., Am J Clin Nutr. 2007 Sep;86(3):580-7

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