“The caffeine has a half-life of four to six hours,” Shearer said. “This elevated glucose/insulin response is going to last a good chunk of the day.”
No one is sure why caffeine affects the body’s ability to metabolize sugar, said Danielle Battram, a professor of food and nutrition at Brescia University College in Ontario.
Caffeine might directly interfere with insulin’s ability to control sugar levels, Battram said, or it might hamper the function of insulin by promoting the release of hormones like adrenaline that work counter to insulin.
Although this study didn’t look at long-term effects, it raises concerns about the role that caffeine-laden energy drinks might play in future risk of type 2 diabetes, Shearer said.
“For individuals who are susceptible to developing type 2 diabetes down the road, this could hasten the disease along,” she said.
However, these findings shouldn’t concern people who drink coffee, Shearer said, even though a 14-ounce cup of Dunkin’ Donuts coffee contains 178 milligrams of caffeine and a 16-ounce cup of McDonald’s java has 133 milligrams.
“There is really good data to show that drinking a cup of coffee is beneficial for you,” Shearer said. “That’s because, believe it or not, coffee is the main source of antioxidants for most North Americans.”
The caffeine in coffee comes in a plant-based form, accompanied by lots of other beneficial compounds, Shearer said. On the other hand, energy drinks contain a processed form of powdered caffeine that more directly affects a person’s metabolism, she explained.
NEXT: Do I Have An Addictive Personality?
Copyright © 2015 HealthDay