Stigmastanols, or Sitostanol, is a saturated form of plant sterols. It is manufactured commercially from vegetable oils and the oil from pine wood tree pulp; adding canola oil makes it fat-soluble. Sitoastanol is helpful because it competes with cholesterol for the limited space in mixed micelles. Sitostanol is both unabsorbable and tasteless. There is some concern that sitostanol decreases fat absorption and dietary beta-carotene absorption. However, sitoastanol has been found to help lower cholesterol levels and is found to be well tolerated by the body.