Does Coffee Have an Impact on Blood Sugar?

While some research has indicated that moderate amounts of caffeine may be beneficial in the prevention of type II diabetes, recent literature has indicated otherwise, especially if intake of caffeine is high.

A recent article published in Diabetes Care 2008; 31(2):221-2, examined blood glucose levels in those with type II diabetes over a 24 hour period; test subjects were given caffeine pills equivalent to about four cups of coffee per day versus placebo.

Those taking caffeine pills showed a significant impact on glucose regulation causing an overall net increase of glucose level over 24 hours of 8%; caffeine also resulted in a significant impairment in the management of glucose after meals; specifically, a mean 9% increase in blood glucose following breakfast, 15% elevation following lunch and 26% elevation following dinner.

The researchers postulated that caffeine may interfere with the metabolic process that shifts glucose from the blood into muscle and other cells in the body where it is used for fuel. Another possible reason for the increase in blood glucose may be that caffeine triggers the release of adrenaline, a hormone that releases stored sugar from the liver.

In either case, as part of a healthy dietary regimen but especially for those with poorly regulated blood sugar, reducing or eliminating caffeine may be necessary. As always, eating a diet low in simple sugars, with emphasis on complex carbohydrate, protein and essential fatty acids (eg. olive oil) and water is fundamental.