Raylene Reimer worked with a team of researchers from the University of Calgary, Canada, to carry out the weaning experiments in 18 litters of rats. Six litters were placed on each of three diets: high prebiotic fiber, high protein and normal control. They consumed these diets until they were 14 weeks old, when they were switched to a high fat, high sugar diet for a further six weeks. Reimer said, "After a weaning diet high in protein, the rats demonstrated an increase in body weight and fat mass in response to the high energy diet. They also showed higher energy intake than the fiber-diet rats".
This is the first study to investigate the long-term effects of high protein or fiber diets during development on the response to future food intake. Speaking about the results, Reimer said, "Overall, it appears that a long-term diet high in protein, when mismatched with a high energy challenge, has negative effects on body mass and hormones and genes involved in glucose and lipid metabolism. However, a fiber-enriched diet may provide some protection".