Imagine waking up to a heart-healthy breakfast of whole-wheat toast, orange juice, low-fat yogurt and scrambled eggs. Scrambled eggs? With the addition of a little-known, but perfectly safe, substance known as beta sitosterol, even scrambled eggs could be deemed heart-healthy. What is this mysterious substance?

Beta sitosterol is a naturally occurring substance found in grains and vegetables oils, particularly corn oil and rice-bran oil. Both plants and animals make sterols. The major sterol in animals is cholesterol; in plants it's beta sitosterol. Research has shown that humans absorb cholesterol slowly, but beta sitosterol is not absorb at all.

"The compounds are very similar chemically and beta sitosterol competes for dietary cholesterol absorption," said Dr. Margo Denke assistant professor of internal medicine and a researcher in the Center for Human Nutrition at UT Southwestern. This has been known since the '50s, and it explains why corn oil was found to be the best oil in terms of lowering cholesterol because not only is it low in saturated fats, but it also has very high amounts of beta sitosterol."

In 1982 Dr. Scott Grundy, director of The Center for Human Nutrition, discovered that the "judicious addition of beta sitoserol... to meals containing cholesterol-rich foods will result in a significant decrease in cholesterol absorption, with a consequent decrease in plasma cholesterol." His study, which involved nine adults, was published in The American Journal of Clinical Nutrition.

The 1982 study was certainly not the last word on the subject. Drs. Denke and Grundy are just completing a new study in which preliminary results indicate that beta sitosterol lowers low-density lipoprotein, the "bad" cholesterol, a small amount- about 6 milligrams per deciliter. "We're investigating it as a dietary adjunct," Dr. Denke said. "We asked the question, 'Is there anything a person can do that still uses the benefits of diet to get additional cholesterol lowering?' We looked at beta sitosterol in pill form and documented that you can indeed lower cholesterol somewhat in people who are already consuming diet.

"Dietary cholesterol takes time to be absorbed and therefore is susceptible to disruption. With plant sterols, the body thinks they're like cholesterol, tries to absorb them but can't, and, in the meantime, cholesterol passes by. The important thing is that beta sitosterol reduces dietary cholesterol absorption." Dr. Denke said there's no harm in adding beta sitosterol to your diet. It can be purchased in some health-food stores in either capsule or liquid form. If using the liquid form, it should be sprinkled directly on the cholesterol containing food. It's most effective, however, when it's used in scrambled eggs to block the absorption of cholesterol, said Dr. Grundy. "It renders eggs innocuous," he said. "The message here is that eggs can be made safe."