MINNEAPOLIS (WCCO) – Almost all of us get an extra jolt every day from a drink with caffeine. We’re a nation that borders on addiction.

So is caffeine hazardous to our health?

Researchers say the average American drinks three, 12-ounce caffeinated drinks each weekday. A lot of us are drinking much more.

It is our national past time. The morning, then afternoon, then evening trip to coffee shops like Dunn Brothers.

Dr. Michael Howell is a neurologist at University of Minnesota Medical School and a sleep specialist at Fairview Southdale. He says there are both health benefits and risks associated with caffeine.

“The downside of caffeine is that it indicates we’re not sleeping well in general. Ninety percent of us drink caffeine or some other stimulant beverage on a daily basis,” Howell said.

Brain scans before and after drinking caffeine shows a much lower blood flow to the brain, a result of the blocking of the chemical adenosine.

“There’s a molecule in the brain called adenosine, builds up over the night. One of the molecules that helps make us sleepy. Caffeine blocks the effect,” said Howell.

Dr. Scott Sakaguchi, a heart rhythm expert at the University of Minnesota, says doctors know that caffeine can cause electrical changes in the heart, but so far they haven’t found anything bad about those changes.

“We can document electrical changes in the heart, but the question becomes: ‘Are those electrical changes clinically significant?’ Some patients with arrhythmias will get worse with caffeine, but other patients with arrhythmias don’t notice any difference whether they stop or continue caffeine,” Sakaguchi said.

Dr. Howell adds that research would have alerted us already to any catastrophic effects of the drug.

“I think there’s cause to be concerned but I wouldn’t be alarmed about it. I think if this was truly a devastating product it would have become more obvious to us,” he said.

Caffeine, in small doses, can help us focus better and stay alert when we’re tired. And coffee drinkers are less likely to have type 2 diabetes, Parkinson’s and certain kinds of cancer.

To be clear, that doesn’t mean that caffeine causes those positives – but it is something scientists are looking at closer.

Caffeine is the most used drug in the world, so why don’t we know more? Researchers say it’s hard to isolate the drug’s effects because it seems to have a different result between genders and between body types.