"The magic ingredient or what I'm calling beneficial saturated fat is stearic acid," he said. Combining stearic acid-rich beef tallow with soybean-derived sterols boosts the cholesterol-lowering power.
Commercially available plant sterol additives are gooey, sticky substances. They stick to food manufacturing equipment.
Carr's compound is easily made into a powder that theoretically could be added to diverse foods, from breakfast cereals and drinks to dairy products and even chocolate.
"We think this powder is going to be much easier to work with and have a much broader application," he said.
Carr is testing his compound's effectiveness in animal studies and exploring how best to commercialize it to benefit consumers. The university is patenting this technology.
So far, results are impressive.
Carr's College of Education and Human Sciences team compared his compound to a commercially available plant sterol product in hamster feeding trials. The compound lowered LDL, or bad, cholesterol about 70 percent, compared with 10 percent using the commercial sterol additive.
While hamsters are a good model for humans, they aren't people. Carr hopes to get funding for human clinical studies.
Commercial plant sterol additives and the team's plant sterol/stearic acid compound both work by blocking cholesterol absorption in the small intestine. Typically, the body absorbs 50-60 percent of cholesterol in the gastrointestinal tract, he said. Excess cholesterol winds up in blood where it can contribute to heart disease.
"With our compound, absorption is in the 3 to 5 percent range," Carr said. "That's highly effective."
Carr is in the midst of a hamster study comparing the compound to a commercial statin drug.
"Our preliminary data indicates that it's as good or better than the statin drugs," he said. He'll have more definitive answers later this year.
Americans take about 2 million daily doses of statins, such as Lipitor, making them the nation's most widely prescribed drugs, Carr said. Statins help millions lower their cholesterol, but there is some concern about their potential for liver and muscle damage.
If the new compound proves effective in further studies, it might provide a new cholesterol management tool.
"The beauty of this is that our compound passes right through the GI tract and takes cholesterol with it. It's never absorbed into the body so there are no toxicity issues," he said.
This research is conducted in cooperation with the university's Agricultural Research Division.