UF Researchers Hope To Shed Light On Questions Brewing Over Caffeine Consumption

August 18, 1997

GAINESVILLE—Tobacco and nicotine are under fire and going up in flames. Now coffee and caffeine are the latest substances to be put under the addiction microscope.

University of Florida researchers are studying the substances’ physical and mental effects, which could have broad implications for optimizing human performance, says UF clinical psychologist Jon Kassel.

Kassel and his colleagues at UF’s College of Health Professions are administering 8-ounce cups of coffee — which may or may not contain varying levels of caffeine — to regular coffee drinkers ages 18 to 65 in a study examining caffeine’s role in determining mood and performance.

After imbibing the beverage, they complete questionnaires and conduct simple performance tasks.

“There is a healthy debate right now as to how significant caffeine habituation is,” said Dr. Allen Neims, professor of pharmacology, therapeutics and pediatrics at UF’s College of Medicine.

“The coffee hour is a big social event. When you visit someone’s house they offer you a cup of coffee. Are you taking it to avoid withdrawal symptoms or are you taking it because you like the fresh feeling it gives you? Or are you taking it out of social custom?”

At first glance, the current interest in caffeine research could have coffee klatchers clutching their cups. But never fear: Physicians aren’t dispensing with the morning cup of joe or the chocolate bar just yet.

Caffeine consumption has certainly never been designated a social ill, though people do become caffeine-dependent, and regular users can experience mild withdrawal symptoms when they abruptly halt their daily habit.

Kassel, an assistant professor in the department of clinical and health psychology at UF, said his team hopes to understand what it is about caffeine that is so rewarding for people.

“Such information could someday lead to more effective treatments for those who want to quit or give up their dependence on caffeine,” he said.

The timing couldn’t be better. Although caffeine has always been in our midst, the American appetite for it seems to be growing.

“Caffeine is the world’s most commonly used mood-altering drug, and it deserves more study,” said Dr. Roland Griffiths, a professor in the departments of psychiatry and neuroscience at the Johns Hopkins University School of Medicine. “In low doses it increases feelings of well-being, the ability to concentrate and energy levels. At high doses, it produces jitteriness, restlessness, anxiety and insomnia.

“Caffeine is so ubiquitous in our culture and so widely accepted that exposure to it is almost universal, and it is habitual,” he added. “So many people are caffeine-dependent that many don’t recognize the extent to which their preference for various foods and beverages is actually being guided by the underlying pharmacology of caffeine, instead of what they think are simply taste and food choices. So it’s a subtle effect.”

Caffeine is widely consumed in coffee, tea, cocoa, soft drinks and chocolate. It also is a component in hundreds of prescription and over-the-counter drugs, ranging from analgesics to cold medicines.

Researchers are quick to emphasize regular caffeine use should not be confused with the abuse of life-threatening drugs such as cocaine or nicotine, or heavy alcohol consumption.

“Caffeine is a drug, but it has nowhere near the kinds of risks associated with conventional drugs of abuse,” Griffiths said. “Nonetheless, it is a very important compound to study further.”

Most published studies have shown caffeine has its biggest effects on performance and mood when people are bored and tired, Neims added.

“In a sense it revitalizes you — the so-called ‘pause that refreshes,’ ” he said. “It’s as much a social issue as it is a pharmacologic one: The issue merits political, social and economic debate as much as it deserves scientific scrutiny.

“Harvard psychobiologist Peter Dews studied the whole issue of habituation, and he said, just remember how we evolved, from creatures who spent most of the time either running away from something that wanted to eat you, or chasing something you wanted to eat. Every so often you’d find safety in a cave to sleep and procreate. Your epinephrine was pumping the rest of the time. Now all of a sudden here we are expected to come to work at 8, leave at 5, and work steadily throughout the day. Is it any surprise we found it a necessity to invent the coffee break?”