Fasting and Experimental Animals, Detrimental or Positive?

Document Type : Review Article


1 Department of Medical Genetics, Mashhad University of Medical Sciences, Mashhad, Iran

2 Department of Nutrition, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

3 Medical Genetics Research Center, Mashhad University of Medical Sciences, Mashhad, Iran


While fasting has been practiced for centuries, its beneficial effects was unknown until recently. This review tries to analyze the current literature of how fasting and intermittent fasting (IF) could affect clinical pathological parameters, learning, mood and brain plasticity. The effects of different ways of fasting on metabolism and stress were also explored. Animal experiments have elucidated fasting and IF could exert positive effects on learning, mood and brain, plus metabolic functions such lowering plasma glucose and insulin level and improvement in lipid metabolism (reduced visceral fat tissue and increased plasma adiponectin level), and an increased resistance to stress. Thus, more clinical studies are necessary to test the effectiveness of fasting and IF in preventing different diseases.


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