Eating Plant Stanols Cuts Cholesterol
Study Shows Chemical Compounds in Fruits and Veggies Can Lower LDL Cholesterol
June 23, 2010 -- Eating 9 grams of stanols a day helped lower LDL "bad" cholesterol by 17.4%, according to a company-supported study from Europe.
Researchers also found that a graded (or linear) effect exists, meaning that the more stanols people ate across a spectrum of doses, the lower their cholesterol.
Elevated cholesterol is a major risk factor for heart attack and stroke. According to the CDC, one in every six U.S. adults has high cholesterol and these individuals face double the risk of heart disease.
Stanols are plant-based chemical compounds found in fruits, vegetables, nuts, and seeds, and are added to everyday foods, such as margarine spreads, to help people reduce their cholesterol levels.
Lowering cholesterol through foods is appealing because it provides people with a way to improve their health without turning to medications. While it has been well-known that stanols reduce LDL -- the unhealthy cholesterol that clogs arteries -- it's been unclear whether higher doses of stanols are even more effective than currently recommended amounts.
Researchers from Maastricht University in the Netherlands and from University of Bonn in Germany placed 93 otherwise healthy people on one of four diets for four weeks. The first group, a comparison group, did not eat any stanol products; a second group ate 3 grams of stanols per day; a third group ate 6 grams; and the fourth group had a daily intake of 9 grams of stanols. They also had to answer a diet questionnaire and provide blood samples before beginning the diet and then during the course of the dietary intervention.
The stanols were in cups of soy-based yogurt and margarine spreads. The foods used in this study were manufactured by a Finland-based functional foods company, Raisio Nutrition Ltd., which also funded this study. The total calories consumed, including the amounts of cholesterol, were about the same between the four diet groups.
Lowering Cholesterol With Stanols
Compared with the comparison group, eating 3, 6, and 9 grams of stanols lowered LDL concentrations by 7.4%, 11.9%, and 17.4%, respectively.
The findings are published in the July issue of American Journal of Clinical Nutrition.
"Recommended daily intakes of plant stanols are usually between 2 and 3 g [grams], at which level the expected reduction in LDL cholesterol is approximately 10%," the researchers write. "It is thought that hardly any further reductions can be achieved at higher intakes. We have now shown for the first time that at daily intakes up to 9 g, the effects of plant stanols provided as their fatty acids lower LDL cholesterol in a dose-dependent linear way."
Liver and kidney function were not affected by eating stanol-enhanced foods for four weeks. However, the researchers note their study was relatively short and that more long-term research would be needed to determine whether there are any risks to liver and kidney function.
The biological mechanisms contributing to this LDL-lowering effect seen among those eating plant stanol foods remain unclear, the researchers say. Moreover, it's uncertain whether dietary stanols would work among patients taking cholesterol-lowering drugs.
In an accompanying editorial, Gustav Schonfeld, MD, from Washington University School of Medicine in St. Louis, said eating enhanced foods that lower cholesterol could help minimize the need for drugs, but more research is needed before people start consuming the large quantities of stanols or plant sterols as described in the current study. The long-term effects of high-dose stanol intake are not known.