Caffeine - What does it do?

 

  By: Dan Palmquist, MD

 

If you look forward to your morning cup of coffee for a little help waking up, you’re not alone. It’s estimated that 85 percent of adults in the United States consume some form of caffeine on a daily basis and that most of this consumption is in the form of coffee at breakfast. The caffeine in coffee acts as a stimulant to the body in a number of ways.

 

Although caffeine is a stimulant, it technically doesn’t speed us up. It actually keeps us (or our brain cells) from slowing down. Each time brain cells fire, they produce a squirt of a chemical called adenosine that serves as an “off” switch that keeps neural activity in check. Caffeine blocks the adenosine -- jamming the switch so that it can’t be turned down.

 

In addition, caffeine dilates blood vessels in the brain and improves circulation there. Therefore, a cup of coffee may help you think and work faster. In fact, some studies have shown that it enhances long-term memory, the ability to learn new information and pay attention. But beware, too much caffeine can have adverse side effects such as the “jitters” or sleep disruptions. Caffeine can linger in your body for up to 15 hours, so an afternoon cup of coffee could disrupt your ability to get to sleep at 10:00 p.m.

 

Caffeine stimulates nerve cells and can increase heart rate and blood pressure, which is not desirable for people who have heart disease, high blood pressure or are at risk for these conditions.

 

People who are predisposed to anxiety disorders should also stay away from caffeine. Its stimulant effects can lead to sweaty palms, a pounding heart and ringing in the ears -- which can trigger full-blown panic attacks for some people.

 

We all know that caffeine is found in coffee. But it can be found (either naturally or as an additive) in a number of other foods and beverages as well. A seven-ounce cup of regular coffee contains about 100 milligrams of caffeine; a 12 ounce serving of iced tea has about 70 mg; 12 ounces of cola has nearly 50 mg; an ounce of chocolate contains 15 mg; and a cup of decaffeinated coffee contains about 5 mg. Hot chocolate, a chocolate doughnut and coffee flavored ice cream all contain caffeine as well.

 

Caffeine’s effects on the brain have been shown to alleviate some types of headaches. Therefore, another caffeine source is certain pain reliever medications. Different brands can contain anywhere from 32 to 100 milligrams in a single tablet.

 

If you’d like to cut back on your caffeine consumption, the best way to do so is gradually. Going cold turkey might cause caffeine withdrawal, which could make you feel mentally foggy with an inability to concentrate. So take it slowly. Cut back by one or two cups each day until you are at a more desired, moderate level of caffeine intake. For most people, it probably isn’t necessary to cut caffeine out of the diet completely. The general consensus seems to be that a moderate amount of caffeine -- a couple of cups of coffee each day -- isn’t going to pose a health concern for most people.

 

So go ahead, savor that cup of java in the morning. Then switch to water -- just make sure it’s the decaffeinated kind.

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Dr. Palmquist is a family practice physician at Raiter Clinic.