Caffeinated coffee and other beverages containing caffeine can make it harder for diabetics to control their blood sugar. No evidence shows that unsweetened decaffeinated coffee has negative effects on diabetics, however. Diabetics who drink caffeinated coffee should consider switching to decaf.
Caffeine and Blood Sugar
In 2004, Dr. James Lane and fellow Duke University researchers conducted a study investigating the effects of caffeine on blood sugar in diabetics. The study, published in "Diabetes Care," found that when diabetic subjects took 250 mg doses of caffeine at breakfast and lunch, their blood sugar levels were 8 percent higher on average than on days when they took placebos. Subjects also experienced greater spikes in blood sugar after breakfast, lunch and dinner on days when they took caffeine than on days they took placebos.
Decaffeinated Coffee
Dr. Rob van Dam of Harvard University School of Public Health suggests that, unlike caffeinated coffee, decaffeinated coffee may actually help diabetics control their blood sugar. He suggests that diabetics switch to decaf coffee rather than quitting coffee completely. To keep the coffee from impacting their blood sugar levels, diabetics should drink decaffeinated coffee black and with artificial sweeteners rather than sugar.
Coffee and Health
Studies show that regular consumption of up to six cups of coffee per day does not increase the risk of major health problems or death from any cause, according to Dr. Rob van Dam. Research has shown that regular coffee consumption may reduce the risk of Parkinson's disease, liver cancer, liver cirrhosis and cardiovascular disease. Regular coffee consumption may also reduce the risk of developing type 2 diabetes.
Other Smart Beverage Choices
Other beverages that don't negatively affect diabetics' blood sugar include those with fewer than 20 calories and less than 5 g of carbohydrates per serving, notes MayoClinic.com. Options include sugar-free, decaffeinated diet soda, carbohydrate-free and sugar-free drink mixes and flavored water, and sugar-free tonic water and club soda.
