Stevia and Plant Sterols

As a naturally occurring noncaloric sweetener, stevia is a good option for individuals seeking to lose weight, control blood glucose levels, and reduce their intake of refined sugar. Unlike artificial sweeteners that have been associated with an increased risk of diabetes, stevia and its components—steviosides—have actually been shown to improve blood glucose control and lower blood pressure.^[1, 2]

One placebo-controlled study in particular found that supplementing with 500 mg of stevioside powder three times daily over two years in patients with high blood pressure resulted in a decrease in blood pressure from 150/95 to 140/89. Notably, these effects were noted as early as one week into the study.^[2] Similarly, another study found that stevia consumption as 1 g stevioside per day, taken with a test meal, reduced the increase in blood glucose following the meal. This decrease was to the magnitude of 40%, and authors concluded that “[s]tevioside may be advantageous in the treatment of type 2 diabetes.”^[1]

Plant sterols are best-known for their role in lowering cholesterol. The blood test for cholesterol, called a cholesterol panel or a lipid panel, consists of five markers: total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides, and ratio of TC:HDL. Of these, LDL is popularly known as “bad cholesterol,” and HDL is known as “good cholesterol.”

Plant sterols have been shown to lower both total cholesterol as well as LDL or “bad cholesterol.”^[3] Data from meta-analyses show that plant sterols can effectively lower LDL between 10% and 15% at a dose of 2 g per day.^[4] Plant sterols have long been thought to block intestinal absorption of dietary cholesterol, and newer research indicates that plant sterols may also have effects on the liver with respect to inhibiting cholesterol synthesis and/or elimination. Because of their inhibitory effects on cholesterol absorption, plant sterols need to be taken with meals.

1. Gregersen, S., et al. “Antihyperglycemic effects of stevioside in type 2 diabetic subjects.” Metabolism Vol. 53, No. 1 (2004): 73–76.
2. Hsieh, M.H., et al. “Efficacy and tolerability of oral stevioside in patients with mild essential hypertension: A two-year, randomized, placebo-controlled study.” Clinical Therapy Vol. 25, No. 11 (2003): 2797–2808.
3. Scholle, J.M., et al. “The effect of adding plant sterols or stanols to statin therapy in hypercholesterolemic patients: Systematic review and meta-analysis.” Journal of the American College of Nutrition Vol. 28, No. 5 (2009): 517–524.
4. Musa-Veloso, K., et al. “A comparison of the LDL-cholesterol lowering efficacy of plant stanols and plant sterols over a continuous dose range: Results of a meta-analysis of randomized, placebo-controlled trials.” Prostaglandins, Leukotrienes, and Essential Fatty Acids Vol. 85, No. 1 (2011): 9–28.