A novel form of vitamin B3 in milk given in a high dose to mice fed a fatty diet seemed to help prevent obesity, U.S. and Swiss researchers said. Dr. Anthony Sauve of Weill Cornell Medical College in New York and Dr. Johan Auwerx of Federal Polytechnic School in Lausanne, Switzerland, said high doses of the vitamin precursor, nicotinamide riboside -- a cousin of niacin -- prevented obesity in mice fed a fatty diet and also increased muscle performance, improved energy expenditure and prevented diabetes development, all without side effects. This form of vitamin B3 is found in milk in small quantities. Auwerx said the ability to give the animals sufficient doses of nicotinamide riboside was made possible by Sauve and colleagues. \"This study is very important. It shows that in animals, the use of NR offers the health benefits of a low-calorie diet and exercise -- without doing either one,\" Sauve said in a statement. Sauve invented a simple method for efficiently synthesizing nicotinamide riboside in large scale. \"The research also suggests that the effects of nicotinamide riboside could be even broader,\" Sauve said. \"The bottom line is that nicotinamide riboside improves the function of mitochondria, the cell\'s energy factories. Mitochondrial decline is the hallmark of many diseases associated with aging, such as cancer and neurodegeneration and nicotinamide riboside supplementation boosts mitochondrial functioning.\" The findings were published in Cell Metabolism.