Final answer:
Plant stanols or sterols are added to food products such as margarine to help lower high cholesterol, by blocking the absorption of dietary cholesterol, which is linked to heart disease.
Step-by-step explanation:
Plant stanols and sterols are added to spreads like margarine to help manage high cholesterol. These substances can block the absorption of cholesterol in the digestive system, which can help to lower levels of low-density lipoprotein (LDL), or "bad" cholesterol.
An increase in LDL is associated with plaque buildup in arteries, leading to heart disease. It is crucial to monitor dietary intake of trans fats found in some margarines, peanut butter, and shortening, as these can increase LDL levels and the risk of heart disease. Instead, a diet with unsaturated fats such as canola oil and one that is rich in fruits, vegetables, lean meats, and whole grains is recommended to maintain heart health.