Kefir drink causes a significant yet similar improvement in serum lipid profile, compared with low-fat milk, in a dairy-rich diet in overweight or obese premenopausal women: A randomized controlled trial

Background: Controversy exists as to whether the lipid-lowering properties of kefir drink (a fermented probiotic dairy product) in animal models could be replicated in humans.

Objective: To assess and compare the potential lipid-lowering effects of kefir drink with low-fat milk in a dairy-rich diet in overweight or obese premenopausal women.

Methods: In this 8-week, single-center, multiarm, parallel-group, outpatient, randomized controlled trial, 75 eligible Iranian women aged 25 to 45 years were randomly allocated to kefir, milk, or control groups. Women in the control group received a weight-maintenance diet containing 2 servings/d of low-fat dairy products, whereas subjects in the milk and kefir groups received a similar diet containing 2 additional servings/d (a total of 4 servings/d) of dairy products from low-fat milk or kefir drink, respectively. At baseline and study end point, serum levels/ratios of total cholesterol (TC), low- and high-density lipoprotein cholesterol (LDLC and HDLC), triglyceride, Non-HDLC, TC/HDLC, LDLC/HDLC, and triglyceride/LDLC were measured as outcome measures.

Results: After 8 weeks, subjects in the kefir group had significantly lower serum levels/ratios of lipoproteins than those in the control group (mean between-group differences were -10.4 mg/dL, -9.7 mg/dL, -11.5 mg/dL, -0.4, and -0.3 for TC, LDLC, non-HDLC, TC/HDLC, and LDLC/HDLC, respectively; all P < .05). Similar results were observed in the milk group. However, no such significant differences were found between the kefir and milk groups.

Conclusion: Kefir drink causes a significant yet similar improvement in serum lipid profile, compared with low-fat milk, in a dairy-rich diet in overweight or obese premenopausal women.