Sterols are a type of lipid, which are organic compounds that include fats and oils. They are essential components of cell membranes and play a crucial role in maintaining their structure and fluidity. The most well-known sterol is cholesterol, which is found in animal cells and is important for producing certain hormones and vitamin D. In addition to cholesterol, there are plant sterols, known as phytosterols, which can help lower cholesterol levels in humans. These compounds are found in various foods, such as nuts, seeds, and vegetable oils. Consuming sterols can contribute to heart health by reducing the absorption of dietary cholesterol in the intestines.