After a small study carried out at the Duke University Medical Center in North Carolina, US researchers claim to have found a link between caffeine intake at mealtimes and increased glucose and insulin levels among people with type 2 diabetes.
Classed as an epidemic by the World Health Organisation, at least 171 million people worldwide suffer from diabetes, a figure likely to more than double to 366 million by 2030. The American Diabetes Association estimates that at least 90 per cent of the 17 million Americans diagnosed with diabetes have type 2.
Writing in the July 2004 edition of Diabetes Care, researchers James Lane, Christina Barkauskas, Richard Surwit, Mark Feinglos say they tested the effects of caffeine on fasting glucose and insulin levels and on glucose and insulin responses to a mixed-meal tolerance test (MMTT).
In the double-blind, placebo-controlled, cross-over study, 14 habitual coffee drinkers (11 men and three women, aged between 61 to 69 years old) who had at least a six-month history of type 2 diabetes, took their medications, had their blood tested and then were given caffeine capsules. Blood was taken after this, and then after giving the volunteers a liquid meal supplement.
After the liquid meal, those who were given caffeine had a 21 per cent increase in their glucose level and insulin rose 48 per cent although caffeine had little effect on glucose and insulin levels when the volunteers fasted.
If these findings are confirmed through further research, they could see people with type 2 diabetes turning to coffee alternatives, and as the figures rise for diabetes, this could become a considerable market.
Last month FoodNavigator.com reported that scientists in Brazil had identified naturally growing caffeine-free coffee plants, paving the way for cheaper processing methods for makers of decaffeinated coffee.
Part of a breeding programme to come up with low-caffeine strains, the discovery of the decaffeinated version of Coffea arabica, the most cultivated and consumed coffee in the world, at the State University of Campinas in Brazil could lead to cheap alternatives to artificially decaffeinated coffee on the market today.
Decaffeinated coffee accounts for about 10 per cent of the world coffee market, according to the National Coffee Association in the US. Industrial methods used today to decaffeinate coffee use organic solvents and carbon dioxide to remove the caffeine from the beans, but in the process tend to deplete necessary flavour compounds.
Reporting recently in Nature, Paulo Mazzafera, who co-discovered the plants, said he hoped his discovery would help those who find it physically difficult to tolerate caffeine. People with type 2 diabetes may fall into this category.