When the hormone's job is done, another enzyme switches off the insulin receptor. Chromium also inhibits the shut-off enzyme's action, Anderson says. The element offers dual benefits.
Unfortunately, Anderson observes, the modern diet of highly processed foods is low in chromium. What's more, foods high in sugar stimulate the body to lose chromium.
The formulation of currently available chromium supplements doesn't permit the body to absorb the element efficiently, Anderson says. However, his team has just received a patent for a new formulation, called chromium histidine, that in human trials results in absorption of about 50 percent more chromium than conventional supplements do, he says.
It was during tests of the new chromium supplement that Anderson and his colleagues stumbled onto an entirely different antidiabetes substance in, of all things, apple pie. During the early stages of one study, the researchers were attempting to disrupt some volunteers' blood sugar control by feeding them a low-chromium diet that included pie. Surprisingly, these volunteers' blood sugar remained under control.
Subsequent test-tube studies showed that cinnamon in the pie was boosting insulin activity, as chromium does, and thus controlling blood glucose. The spice turned out to be the "best thing we ever tested" for that purpose, Anderson says.
Anderson and his colleagues recently studied 60 people with type 2 diabetes. The researchers gave the participants capsules containing either cinnamon or wheat flour. The 30 people getting daily doses of 1, 3, or 6 grams of cinnamon for 40 days experienced an 18 to 29 percent drop in blood glucose, compared with their values at the beginning of the study. A gram of cinnamon is about one-half a teaspoon, says Anderson. Volunteers getting wheat flour for 40 days showed no such benefit.
Cinnamon also improved study participants' blood-cholesterol and triglycerides concentrations, Anderson's team reported in the December 2003 Diabetes Care.
Subsequently, the scientists found that cinnamon's active ingredients are polyphenol polymers with insulinlike action. Anderson's team described those experiments in the Jan. 14 Journal of Agricultural and Food Chemistry.
Cloves, bay leaves, and other spices show enzymatic effects similar to those of cinnamon, Anderson has found, though none approaches cinnamon's potency.