Differential effects of Chinese high-fat dietary habits on lipid metabolism: mechanisms and health implications

Background The traditional Chinese diet blends lard with vegetable oil, keeping the fatty acid balance intake ratio of saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids at nearly 1:1:1. However, the effects of a mixture of lard and vegetable oil on lipid metabolism have never been researched. In the present study, by simulating Chinese high-fat dietary habits, we explored the effects of a mixture of lard and vegetable oil on lipid metabolism. Methods We randomly assigned 50 male C57BL/6 J mice to 5 groups (10 in each group) and fed them lard, sunflower oil (SFO), soybean oil (SBO), lard blended with sunflower oil (L-SFO), or lard blended with soybean oil (L-SBO) for 12 weeks. Results We found that the final body weights of mice in the lard group were significantly higher than those of mice in the SFO and SBO groups. Body fat rate and volume of fat cell of the lard group were significantly higher than those of the SFO, SBO, and L-SBO groups. Liver triglyceride level of the lard group increased significantly compared to the other groups. Although body fat rate and liver triglyceride level in the SBO and SFO groups decreased compared to those in the other groups, the high-density lipoprotein cholesterol/low-density lipoprotein cholesterol ratio were also significantly decreased in the SBO and SFO groups. Conclusions We found that a lard diet induced accumulation of body fat, liver and serum lipids, which can increase the risk of obesity, non-alcoholic fatty acid liver disease, and atherosclerosis. The vegetable oil diet resulted in cholesterol metabolism disorders even though it did not lead to obesity. The mixed oil diet induced body fat accumulation, but did not cause lipid accumulation in the liver and serum. Thus, differential oil/fat diets have an impact on differential aspects in mouse lipid metabolism. Graphical abstract