Caffeine in coffee, energy drinks absorbed at same rate, WSU study says

Slamming an energy drink instead of slowly sipping coffee in the morning might not be a bad idea after all. In fact, the two are practically the same.

In a study out of Washington State University, researchers recently discovered almost no difference between the amount of caffeine absorbed into the blood from coffee and from energy drinks, assuming similar caffeine content. The study also showed relatively no difference in the levels of caffeine in the blood between rapidly consuming the two drinks – hot or cold – versus drinking them slowly.

These findings come on the heels of some municipalities, such as Chicago and New York City, toying with the idea of putting restrictions on nonalcoholic energy drinks, and some colleges banning them altogether.

The study, which was paid for by the American Beverage Association and was conducted early last year, was headed by John White, a professor at the WSU College of Pharmacy. White became interested in testing the absorption of caffeine into the bloodstream and putting to rest the popular opinion that energy drinks create an unsafe “jolt” of energy, while coffee provides a safer, more drawn-out buzz.

“The concern that was most salient in my mind was that energy drinks are cold, they are intended to be consumed quickly, and so therefore, when these people drink energy drinks, they’re probably getting this enormous boost of caffeine,” he said. “Versus the person who sits in Starbucks who casually has a cup of coffee in 20 minutes.”

White and his team of researchers had 24 healthy volunteers aged 18 to 30 drink sugar-free coffee and energy drinks containing 160 milligrams of caffeine. To study the affect of “spiking” levels of caffeine, the volunteers consumed cold coffee and energy drinks quickly in two minutes, slowly in 20 minutes, and consumed hot coffee slowly in 20 minutes.

The results, White said, are contrary to what most people would expect.

“The kinetic curves in all five conditions were essentially the same,” he said. “In fact, coffee was absorbed a little bit more rapidly and at a higher peak concentration than energy drinks. But from a practical standpoint, they were all the same.”

White said the study chose not to focus on caffeine’s absorption into the brain, which varies on two major factors: how quickly a person metabolizes caffeine, and the person’s genetic array of caffeine receptors in the brain. Meaning, some people may experience a noticeable difference between energy drinks and caffeine compared to others, though the amount of caffeine in their blood is similar.

White also said the American Beverage Association, which represents the nonalcoholic beverage industry, most likely granted the research in hopes of a positive finding that energy drinks are no more harmful than coffee. But, he said, the funding had no impact on the research.

“Even if the results had been damning, they wouldn’t have been able to stop the publication,” he said. “They were hands-off.”