Caffeine in Your Diet

What is caffeine?

Caffeine is a stimulant that occurs naturally in tea leaves, coffee beans, cocoa beans, and several other foods. While many people enjoy the stimulating effects of caffeine, too much can cause you to have unpleasant side effects.

How does caffeine affect me?

Caffeine stimulates every part of the body:

It stimulates the brain and makes you feel wide awake, energetic, and better able to concentrate.
It increases the heartbeat and improves circulation.
It enables muscles to work better.
It aids digestion by increasing acid production in the stomach.
It stimulates the kidneys to increase the production of urine.

What happens if I take in too much caffeine?

Too much caffeine can overstimulate you and result in:

restlessness, jumpiness, anxiety, and difficulty sleeping
an irregular heartbeat
twitching muscles
nausea
pain in your stomach or intestines.

You also can develop caffeine tolerance. This means you need more and more caffeine to get the desired effect. If you become dependent on caffeine, you have withdrawal symptoms (tiredness, headache, or irritability) from going without it.

How much caffeine is too much?

If you drink a lot of coffee, tea, or cola, you are probably consuming a lot of caffeine. For example, a 5-ounce cup of regular coffee might contain from 30 to 200 mgs of caffeine, depending on the amount of coffee grounds used and whether it was instant or brewed. The average cup of coffee contains 100 mg of caffeine. A 5-ounce cup of tea is likely to contain from 20 to 100 mgs of caffeine. Energy drinks contain around 80 mg of caffeine in an 8-ounce serving.

The best way to decide if you are getting too much caffeine is to look carefully at how it affects you. If you are experiencing any of the symptoms of overstimulation, then you are getting too much.

Does caffeine cause any serious medical problems?

Caffeine may cause problems for people with these medical conditions:

agoraphobia (fear of being in open places)
anxiety or panic attacks
heart arrhythmias or palpitations
heart disease or recent heart attack (within a few weeks)
high blood pressure
insomnia (trouble sleeping)
liver disease
peptic ulcer
premenstrual syndrome (pms).

Should I stop drinking beverages that contain caffeine?

Unless you are very sensitive to caffeine or have symptoms of overuse, there is probably no reason not to enjoy caffeinated drinks. A reasonable amount of caffeine is 200 to 300 mg per day. However, if you drink enough coffee or tea to cause unpleasant symptoms, cut back or switch to drinks that are caffeine-free.

Disclaimer: This content is reviewed periodically and is subject to change as new health information becomes available. The information provided is intended to be informative and educational and is not a replacement for professional medical evaluation, advice, diagnosis or treatment by a healthcare professional.

HIA File NTR4700F.HTM Release 9.0/2006