Sterols are found in plants and augment the body's defenses against disease and aging.
Sterols contain chemical classes of substances that have various effects.
Some, such as carotenoids and flavonoids, act primarily as antioxidants. Others, including the isoflavonoids in soy and the lignins in grain, have specific hormone-like effects. Still others, such as s-allyl cysteine in garlic and limonene in citrus fruit peel, can alter cellular biochemical pathways and improve the elimination of carcinogenic substances. Studies showing the effects of lycopene on prostate cancer has created a lot of interest. Lycopene is present in tomatoes.