Cinnamon spice produces healthier blood

• 17:52 24 November 2003
• NewScientist.com news service
• Debora MacKenzie 

Just half a teaspoon of cinnamon a day significantly reduces blood sugar levels in diabetics, a new study has found. The effect, which can be produced even by soaking a cinnamon stick your tea, could also benefit millions of non-diabetics who have blood sugar problem but are unaware of it.

The discovery was initially made by accident, by Richard Anderson at the US Department of Agriculture's Human Nutrition Research Center in Beltsville, Maryland.

"We were looking at the effects of common foods on blood sugar," he told New Scientist. One was the American favourite, apple pie, which is usually spiced with cinnamon. "We expected it to be bad. But it helped," he says.

Sugars and starches in food are broken down into glucose, which then circulates in the blood. The hormone insulin makes cells take in the glucose, to be used for energy or made into fat.

But people with Type 1 diabetes do not produce enough insulin. Those with Type 2 diabetes produce it, but have lost sensitivity to it. Even apparently healthy people, especially if they are overweight, sedentary or over 25, lose sensitivity to insulin. Having too much glucose in the blood can cause serious long-term damage to eyes, kidneys, nerves and other organs.

Molecular mimic

The active ingredient in cinnamon turned out to be a water-soluble polyphenol compound called MHCP. In test tube experiments, MHCP mimics insulin, activates its receptor, and works synergistically with insulin in cells.

To see if it would work in people, Alam Khan, who was a postdoctoral fellow in Anderson's lab, organised a study in Pakistan. Volunteers with Type 2 diabetes were given one, three or six grams of cinnamon powder a day, in capsules after meals.

All responded within weeks, with blood sugar levels that were on average 20 per cent lower than a control group. Some even achieved normal blood sugar levels. Tellingly, blood sugar started creeping up again after the diabetics stopped taking cinnamon.

The cinnamon has additional benefits. In the volunteers, it lowered blood levels of fats and "bad" cholesterol, which are also partly controlled by insulin. And in test tube experiments it neutralised free radicals, damaging chemicals which are elevated in diabetics.

Buns and pies

"I don't recommend eating more cinnamon buns, or even more apple pie - there's too much fat and sugar," says Anderson. "The key is to add cinnamon to what you would eat normally."

The active ingredient is not in cinnamon oils. But powdered spice can be added to toast, cereal, juice or coffee.

Anderson's team were awarded patents related to MHCP in 2002. But the chemical is easily obtained. He notes that one of his colleagues tried soaking a cinnamon stick in tea. "He isn't diabetic - but it lowered his blood sugar," Anderson says.

The group now plans to test even lower doses of cinnamon in the US, and also look at long-term blood sugar management with the spice.

Journal reference: Diabetes Care (vol 26, p 3125)