Almost everyone has eaten cholesterol-lowering foods like walnuts, salmon, and oatmeal. But what's a plant sterol or stanol? And do you really want to eat it?
Most experts say yes. "Eating sterol and stanol-containing foods is an easy way to lower your LDL cholesterol, which helps reduce the risk of heart disease," says Ruth Frechman, RD, a spokeswoman for the American Dietetic Association (ADA).
Plant sterols and stanols are substances that occur naturally in small amounts in many grains, vegetables, fruits, legumes, nuts, and seeds. Since they have powerful cholesterol-lowering properties, manufacturers have started adding them to foods. You can now get stanols or sterols in margarine spreads, orange juice, cereals, and even granola bars.
How Do Plant Sterols and Stanols Help?
On a molecular level, sterols and stanols look a lot like cholesterol. So when they travel through your digestive tract, they get in the way. They can prevent real cholesterol from being absorbed into your bloodstream. Instead of clogging up your arteries, the cholesterol just goes out with the waste.
What's the Evidence?
"Plant stanol esters help block the absorption of cholesterol," Frechman tells WebMD. "Research shows that three servings a day can reduce cholesterol by 20 points."
Experts have been studying the effects of food fortified with plant sterols for decades. One important study of people with high cholesterol found that less than an ounce of stanol-fortified margarine a day could lower "bad" LDL cholesterol by 14%. The results were published in The New England Journal of Medicine.
A more recent study from the University of California Davis Medical Center looked at the effects of sterol-fortified orange juice. Of 72 adults, half received regular orange juice and half the fortified OJ. After just two weeks, the people who drank the stanol-fortified juice had a 12.4% drop in their LDLcholesterol levels. The results were published in the journal Arteriosclerosis, Thrombosis, and Vascular Biology.
The FDA gave these products the status of a "health claim." This means that experts widely agree on the cholesterol-lowering benefits of stanols and sterols. It also allows manufacturers to advertise the heart-healthy benefits on labels.