The first inkling that cinnamon could be more than a spice in your muffin arose from studies done by Richard A. Anderson, at the Human Nutrition Research Center in Beltsville, Md., an arm of the U.S. Department of Agriculture. Scientists there were testing foods that might boost the efficiency of insulin in type 2 diabetics and found "the champ" to be apple pie. Insulin helps the body to metabolize sugar.
"We thought it might be the apples. It wasn't," said Anderson. "We analyzed every ingredient of the pie and finally found the cinnamon." Follow-up test tube studies revealed the most active ingredient in cinnamon to be methylhydroxy chalcone polymer, which the researchers said helps convert glucose (sugar) to energy.
One of Anderson's associates, Alam Khan, a Fulbright scholar from Pakistan, subsequently conducted a study in Pakistan on 60 people with type 2 diabetes. He found that one-quarter teaspoon of cinnamon taken twice daily for 40 days did lower participants' blood sugar levels. Khan's results were published in Diabetes Care, the journal of the American Diabetes Association.
Several subsequent studies by other researchers have confirmed Khan's results, while others have failed to replicate his findings.
Dr. Irwin Klein, professor of medicine and endocrinology at North Shore University Hospital in Manhasset, cited a study in the Journal of Nutrition that found cinnamon ineffective. "Why look for such an agent when we have so many effective ways to control sugar in [type 2 diabetes]?" asked Klein.
Dr. Andrew Greenberg, director of the Obesity and Metabolism Laboratory, USDA Human Nutrition Research Center on Aging at Tufts University in Boston, said that although the talk about cinnamon is "intriguing," there needs to be more research.
"I don't think it's something we can recommend now as a therapeutic agent. The jury is still out on this," said Greenberg.
But in South Carolina and elsewhere throughout the world, according to Anderson, physicians are beginning to acknowledge the benefits of cinnamon. Anderson recommends cinnamon extract capsules, available without a prescription.
"People think they can just sprinkle it on their food once in a while, but basically that does not work. We say you have to have one-quarter to one-half a teaspoon twice a day."
He also warns that anyone on medication for type 2 diabetes or who has been told they have an elevated blood sugar level should consult their physician before self-administering cinnamon.
Hart, meanwhile, said his patients are startled when he recommends cinnamon.
"They think I'm a nut case," he said. "But I tell them, don't laugh. Try it."