Objective: To modify the traditional obese model and set up an ideal animal model for evaluating the weight-reducing effect of functional health foods.
Method: Twenty rats randomly selected from 50 healthy male SD rats and fed with basic diet and high fat diet respectively for 6 weeks were used as control group and obese group for traditional model. Ten rats with the lowest body weight in the rest 30 rats fed with high fat diet for the first 2 weeks were excluded as obesity-resistant rats. The 20 obesity-proneness rats were then randomly divided into control group and obese group respectively for modified model. The rats in the control group of modified model were switched to basic diet and the rats in the obese group of modified model were still fed with high fat diet for another 4 weeks. Then the body weight, fat-pad weight, total fat/body weight, plasma lipids and glucose contents were determined and compared.
Results: All the obese-related indices in obese groups were significantly worse than those of their respective control rats in both traditional and modified models. The obese-related indices of obese rats in the modified model were worse than those in the traditional model, and the individual variation in a group was relatively smaller in the modified model.
Conclusion: The modified model is more representative and ideal than the traditional model for evaluating weight-reducing functional food.