How much are you getting?
If you think your morning coffee or tea is the extent of your caffeine intake -- or that the stimulant is only in brown-colored beverages and foods -- you may be in for a jolt. Although coffee, tea, soft drinks, and chocolate products are, in descending order, the greatest sources of caffeine, it also comes in unexpected beverages. In addition, the increasingly popular super-size servings deliver an ever more powerful punch.
Sunkist orange soda contains about 40 milligrams of caffeine in a 12-ounce serving, more than you'd get from the same amount of bottled, sweetened iced tea. Mountain Dew, a yellow-colored drink that's a favorite of teenagers, has about 55 milligrams of caffeine in a 12-ounce can. And if you're opting for the health benefits of brewed green tea, you should know it has the same amount of caffeine as black tea -- about 40 milligrams in a cup.
The standard 8-ounce cup of brewed coffee contains 70 to 110 milligrams of caffeine, depending on the type of coffee and the strength of the brew. But "who drinks an 8-ounce cup of coffee?" asks Joan Salge Blake, a clinical assistant professor at Boston University. A
Soft drinks are widely available in 16.9- and 24-ounce bottles. Consume 24 ounces of a soft drink with caffeine and you're getting the equivalent of a cup of brewed coffee. Caffeine is included in the ingredient list, but manufacturers don't have to disclose the amount. The prevalence of caffeine in products marketed to children and teens concerns health officials.
"There's been a huge increase in soda consumption in the last three decades, and with it caffeine consumption," says Carine Lenders, chief of the division of pediatric nutrition at Boston University Medical Center. Children consume about 1 milligram of caffeine per kilogram of body weight a day; adults take in about three times that amount. Problems such as sleep disorders and agitation usually occur after consuming 5 milligrams a day, says Lenders.
However, some people are caffeine-sensitive and can suffer the effects at smaller dosages, according to Blake.
If you're at risk for type 2 diabetes, caffeine may offer some protection, according to a recent study from the Harvard School of Public Health and Brigham and Women's Hospital. In the study of 125,000 participants, men who drank more than six cups of caffeinated coffee a day reduced their diabetes risk by more than 50 percent, and women reduced their risk by nearly 30 percent compared with those who don't drink coffee.
Caffeine may also help provide modest short-term relief for asthma. The chemical makeup of caffeine is related to theophylline, a drug used to treat asthma, according to a British researcher.
BEV BENNETT
