Objective:To observe the effect of combining red yeast rice and Lactobacillus casei(L.casei)in lowering cholesterol in patients with primary hyperlipidemia,the later has also been shown to remove cholesterol in in vitro studies.Methods:A double-blind clinical trial was conducted to evaluate the cholesterol-lowering effect of the combination of red yeast rice and L.casei.Sixty patients with primary hyperlipidemia were recruited and randomized equal y to either the treatment group(red yeast rice+L.casei)or the control group(red yeast rice+placebo).One red yeast rice capsule and two L.casei capsules were taken twice a day.The treatment lasted for 8 weeks,with an extended follow-up period of 4 weeks.The primary endpoint was a difference of serum low-density lipoprotein cholesterol(LDL-C)level at week 8.Results:At week 8,the LDL-C serum level in both groups was lower than that at baseline,with a decrease of 33.85±26.66 mg/dL in the treatment group and 38.11±30.90 mg/dL in the control group;however,there was no statistical difference between the two groups(P>0.05).The total cholesterol was also lower than the baseline in both groups,yet without a statistical difference between the two groups.The only statistical y significant difference between the two groups was the average diastolic pressure at week 12,which dropped by 2.67 mm Hg in the treatment group and increased by 4.43 mm Hg in the placebo group(P<0.05).The antihypertensive activity may be associated with L.casei.Red yeast rice can significantly reduce LDL-C,total cholesterol and triglyceride.Conclusion:The combination of red yeast rice and L.casei did not have an additional effect on lipid profiles. Objective: To observe the effect of combining red yeast rice and Lactobacillus casei (L.casei) in lowering cholesterol in patients with primary hyperlipidemia, the later has also been shown to remove cholesterol in vitro studies. Methods: A double-blind clinical trial was conducted to evaluate the cholesterol-lowering effect of the combination of red yeast rice and L. casei. Sixty patients with primary hyperlipidemia were recruited and randomized equal to either the treatment group (red yeast rice + L.casei) or the control group (red yeast rice + placebo) .One red yeast rice capsule and two L.casei capsules were taken twice a day. The treatment lasted for 8 weeks, with an extended follow-up period of 4 weeks.The primary endpoint was a difference of Serum low-density lipoprotein cholesterol (LDL-C) level at week 8. Results: At week 8, the LDL-C serum level in both groups was lower than that at baseline, with a decrease of 33.85 ± 26.66 mg / dL in the treatment group and 38.11 ± 30.90 mg / dL in the control grou p; however, there was no statistical difference between the two groups (P> 0.05). The total cholesterol was also lower than the baseline in both groups, yet without a statistical difference between the two groups. two groups was the average diastolic pressure at week 12, which dropped by 2.67 mm Hg in the treatment group and increased by 4.43 mm Hg in the placebo group (P <0.05). The antihypertensive activity may be associated with L. casei. Red yeast rice can significantly reduce LDL-C, total cholesterol and triglyceride. Conlusion: The combination of red yeast rice and L. casei did not have an additional effect on lipid profiles.