Objective To analyze the effect of serum fatty acid and insulin resistance in SD rats induced by four types fatty acids: medium-chain saturated fatty acids(MC-SFA,MCF group),long-chain saturated fatty acids(LC-SFA,LCF group),n-6 polyunsaturated fatty acids(n-6 PUFA,SUF group) and n-3 polyunsaturated fatty acids(n-3 PUFA,TUF group).Methods Normal male SD rats were fed on standard laboratory chow(8.23% of calories as fat) or isocaloric high fat diets(44.75% of calories as fat)for 10 weeks.Serum glucose(GLU),s...