Cholesterol-Lowering Efficacy of Plant Sterols in Low-Fat Yogurt Consumed as a Snack or with a Meal

Abstract

Objective: Plant sterols (PS) consumed as a snack may not have the same cholesterol-lowering potential as when consumed with a meal due to poor solubilization. It was hypothesized that the consumption of a single dose, low-fat yogurt rich in PS (1.6 g/d) with a meal over an afternoon snack will lead to favourable changes in plasma lipids, plasma PS concentrations, and cholesterol synthesis without negatively affecting α-tocopherol or carotenoids levels.

Methods: Twenty-six hyperlipidemic males and females completed the randomized trial of three phases (control, single PS dose consumed with a meal, or single PS dose as an afternoon snack) while consuming controlled, low-fat diets. Plasma lipids, cholesterol synthesis rates, plasma PS and serum fat-soluble antioxidants were measured at baseline and after 4 weeks.

Results: Endpoint total cholesterol (TC) levels after the PS snack phase were decreased (p = 0.04) (5.30 ± 0.2 mmol/L) compared to the control phase (5.53 ± 0.2 mmol/L). However, endpoints for TC (5.37 ± 0.2 mmol/L) for PS dose with a meal were comparable to control phase. Low-density lipoprotein-cholesterol tended to be different (p = 0.06) at the end of the intervention phases (3.51 ± 0.1, 3.43 ± 0.1, and 3.33 ± 0.1 mmol/L; control, meal and snack, respectively). Cholesterol fractional synthesis rates were higher (p = 0.007) by 25.8% and 19.5% at the end of the snack and meal phases, respectively, compared with the control phase. Plasma campesterol and β-sitosterol concentrations, adjusted for TC, were higher (p < 0.01) in the snack phase (2.30 ± 0.3 and 0.54 ± 0.1 μmol/mmol, respectively) and in the meal phase (2.00 ± 0.3 and 0.51 ± 0.1 μmol/mmol, respectively) when compared to the control phase (1.81 ± 0.3 and 0.40 ± 0.1 μmol/mmol, respectively). No changes in α-tocopherol or carotenoids levels were detected after adjusting for TC, for all phases.

Conclusion: These results indicate that a single dose of PS in low-fat yogurt, provided as a snack, lowers cholesterol levels but does not alter fat-soluble vitamin or carotenoid concentrations in hyperlipidemic participants.

• cholesterol synthesis
• low-fat yogurt
• plant sterols
• snack
• total cholesterol

• BMI = body mass index
• D = deuterium
• FSR = cholesterol fractional synthesis rate
• GC = gas chromatography
• HDL-C = high-density lipoprotein cholesterol
• HPLC = high-performance liquid chromatography
• LDL-C = low-density lipoprotein-cholesterol
• MECNRU = Mary Emily Clinical Nutrition Research Unit
• NCEP = National Heart, Lung, and Blood Association's National Cholesterol Education Program
• PS = plant sterols
• RBC = red blood cells
• TC = total cholesterol
• TG = triglycerides

The assistance of Kristen Rindress, Linda Lapensée and the Mary Emily Clinical Nutrition Research Unit staff in the coordination of the study and in meal preparation are acknowledged. In addition, the authors would like to thank Yvanna Buchanan and Khatima Khalloufi in their assistance for laboratory work. Funding was provided by Danone Vitapole.

Notes

Funding was provided by Danone Vitapole.