Washington: Natural substances extracted from green or unroasted coffee beans can prevent diabetes and improve glucose control, a new study has found.
US researchers found that chlorogenic acids in coffee can help control elevated blood sugar levels and body weight that underpin type 2 diabetes.
Chlorogenic acids are a family of substances that occur naturally in apples, cherries, plums, dried plums and other fruits and vegetables.
Researcher Joe Vinson, who is with the University of Scranton in Pennsylvania, pointed out that coffee – due to its popularity as a beverage – is a major dietary source of these substances.
Large amounts of chlorogenic acids exist in green, or unroasted, coffee beans. However, the high temperatures used to roast coffee beans to make them suitable for use in coffee breaks down much of the chlorogenic acids.
Thus, the focus has been on using concentrated extracts of green coffee beans, which contain higher amounts of chlorogenic acids.
There is significant epidemiological and other evidence that coffee consumption reduces the risk of type 2 diabetes.
“One large study indicated a 50 per cent risk reduction for people who drank seven cups of coffee a day compared to those who drank only two cups a day,” Vinson said.
“The evidence points to chlorogenic acids as the active ingredients in coffee that both prevent diabetes and improve glucose control in normal, pre-diabetic and diabetic people,” Vinson added.
In a previous study, Vinson found that overweight or obese people who took such an extract lost about 10 per cent of their body weight in 22 weeks.
The new study sought to document the effects of various doses of a commercial green coffee extract on the blood sugar levels of 56 men and women with normal blood sugar levels.
They got a glucose tolerance test to see how their bodies responded to the sugar. Then over a period of time, they took 100, 200, 300 or 400 milligrammes (mg) of the extract in a capsule with water.
Follow-up glucose tolerance tests showed how the green coffee extract affected their responses.
“There was a significant dose-response effect of the green coffee extract and no apparent gastrointestinal side effects,” Vinson said.
“All doses of green coffee extract produced a significant reduction in blood sugar relative to the original blank glucose challenge. The maximum blood glucose occurred at 30 minutes and was 24 per cent lower than the original with the 400 mg of green coffee extract and the blood glucose at 120 minutes was 31 per cent lower,” Vinson said.
The study was presented at a American Chemical Society’s meeting in New Orleans.