Caffeine and children, some sound advice

Many adults are dependent on the caffeine in their morning coffee to get them going. But what about kids? Children who regularly drink soda, iced tea and other caffeine-containing beverages and foods may be getting too much. Find out how caffeine can be bad for your kids (and you) -- and how much is too much.

What's wrong with caffeine?

• Caffeine is a stimulant that affects the central nervous system. Too much of it can speed up the heart and cause nervousness, irritability and anxiety. Some research indicates that caffeine can decrease a child's ability to perform certain thinking and muscular tasks.
• Caffeine can disturb sleep. Caffeine takes three to six hours to leave the body, and as a rule, children break down caffeine more slowly than adults. Soda or other caffeine too close to bedtime could make it difficult for your child to go to sleep.
• Caffeine is a diuretic, which means that it causes the body to eliminate water through urination. A child who drinks caffeinated soda is more susceptible to dehydration and will actually need even more water to replace lost fluids, especially in hot weather.
• Caffeinated beverages often replace healthier ones. Soda and tea have no vitamins or minerals and often replace drinks such as milk, orange juice and water, all of which are beneficial for children.
• Significant amounts of caffeine can have toxic effects -- including nausea, vomiting, diarrhea, cramps, muscle twitching, and agitation -- with consumption of as little as 4.5 mg of caffeine per pound of body weight (equivalent to about four sodas for a 50-pound child).
• Caffeine and meds don't always mix. Some medications interact with caffeine. Ask your doctor or pharmacist about the potential interactions of any medications your child is taking.
• Caffeine makes it difficult for the body to absorb calcium, which children need for strong bones and teeth.

How much is too much?

Caffeine sensitivity varies between individuals. As a general rule, however, kids shouldn't have more than 100 mg of caffeine a day. Here are the approximate amounts of caffeine in some beverages and foods:

• 8 ounce coffee: 85 mg
• 1 ounce espresso: 35 mg
• 12 ounce tea: 30 to 70 mg
• 12 ounce Mountain Dew: 54 mg
• 12 ounce Diet Coke: 46 mg
• 1 ounce dark chocolate: 20 mg
• 1 ounce milk chocolate: 6 mg

Many fruit-flavored beverages and liquid cold medicines also contain significant amounts of caffeine, so be sure to check labels.

Your teenager is especially vulnerable to overdoing the caffeine, as teens are making more choices in their own diets -- and sodas are readily available in many schools. Encourage your teen to stay away from soda and order decaffeinated drinks as much as possible. (Remember that "decaffeinated" means that some, not all, of the caffeine has been removed.)

Reviewed by: Patrick S. Pasquariello Jr., MD