Mercy's Dr. Ruth Brocato of Mercy Personal Physicians at Lutherville Discusses Caffeine Sensitivity

Caffeine is the most commonly used stimulant in the world. Eight of 10 people consume it. It can improve alertness and enhance concentration, but for some people, the effects can be not so positive.

The coffee pot in the WBAL-TV newsroom gets a workout, like it does in many workplaces. Approximately 80 percent of adults consume caffeine regularly.

"We all need coffee, right? We can't work the day without coffee," patient Christina Evans said.

Evans used to drink coffee all day long, but she wasn't feeling too great.

"What was going on, I always was feeling like a fast heart beat," Evans said.

Evans came to see Dr. Ruth Brocato, Primary Care Provider specializing in Family Medicine at Mercy Personal Physicians at Lutherville.

The diagnosis?

"I was having too much coffee," Evans said.

How much caffeine is too much? Doctors said up to 400 milligrams a day is generally safe for most adults. That's about four 8-ounce cups of coffee, or 10 cans of cola, or two energy drinks.

"And then there are people who are extremely sensitive, so even one cup of coffee can cause irritability, aggressiveness, palpitations is a common thing that we see, especially in some older women who are dehydrated and anxious," Brocato said.

After eliminating a heart problem as the source of Evans’ palpitations, Brocato zeroed in on caffeine as the culprit, and she was right.

"So she told me to reduce, just to try to have it in the morning, and things got much better," Evans said.

To view family medicine specialist Dr. Ruth Brocato’s interview about caffeine sensitivity, click here.