Influence of daily consumption of probiotic and conventional yoghurt on the plasma lipid profile in young healthy women

BACKGROUND: A number of studies have found conflicting results concerning the modulation of plasma lipids induced by probiotics. Therefore, the aim of this study was to verify and compare the effects of probiotic and conventional yoghurt on the plasma lipid profile of normocholesterolemic women. METHODS: In this study, female volunteers consumed 100 g/day of probiotic (n = 17) or conventional yoghurt (n = 16) for 2 weeks (T1-T2) and 200 g/day for further 2 weeks (T2-T3). A washout phase lasting 2 weeks followed (T4). Total and HDL cholesterol and triglycerides were determined by enzymatic methods; LDL cholesterol was calculated using the Friedewald formula. RESULTS: The average concentration of total cholesterol was consistent throughout the whole study in the control group, but decreased significantly (p < 0.01) in the probiotic group consuming 200 g yoghurt/day (T2-T3). During the period of daily yoghurt intake (T1-T3) the mean HDL cholesterol level increased significantly (p < 0.05) in the probiotic group, resulting in a significant (p < 0.05) improvement of the total/HDL cholesterol ratio. The significant (p < 0.01) reduction of the average plasma LDL cholesterol values found in this period (T1-T3) in the probiotic and the control groups was associated with a significant (p < 0.05) improvement of the LDL/HDL cholesterol ratios in both tested groups. CONCLUSION: Although several lipid parameters changed during the study in both the probiotic and the control group, no significant differences between the groups were observed. Therefore, it can be concluded that the regular consumption of both probiotic and conventional yoghurt for 4 weeks had a positive effect on the lipid profile in plasma of healthy women.