A closer look at caffeine

Caffeine, a mild stimulant that comes from the leaves, seeds or fruits of more than 60 plants, is one of the most comprehensively studied ingredients in the U.S. food supply. To date, no scientific evidence has demonstrated an association between caffeine and any health-related problems including heart disease, hypertension, cancer, osteoporosis, fibrocystic breast disease, ulcers or dehydration.

Most medical and nutrition experts agree that moderate caffeine consumption is safe for otherwise healthy individuals. Although caffeine sensitivity varies from person to person and is affected by many factors, including the frequency and amount of regular intake, body weight and physical condition, the general consensus is that a daily caffeine intake of 300 milligrams, which is equal to about 3 cups of coffee, is safe for most adults. The American Dietetic Association does, however, offer the following advice for individuals who fall in certain categories.

• If you're pregnant or nursing, it's generally a good idea to limit caffeine intake. Although most physicians agree that moderate caffeine consumption during pregnancy is safe, sensitivity may increase during pregnancy. Caffeine can be passed to the baby through breast milk, but consumption of small amounts of caffeine by the mother does not appear to affect the baby.

• If you have an existing medical problem, ask your physician to advise you on caffeine consumption as it may aggravate certain conditions such as gastritis, ulcers and high blood pressure. Particularly, people with stomach problems are advised to avoid caffeinated beverages, and often their decaffeinated counterparts as well, because substances in both tend to stimulate the production of stomach acids that potentially can irritate the stomach lining.

• If you're older, keep in mind that your sensitivity to caffeine may increase with age.

• If you have insomnia, it's a good idea to avoid caffeine-containing sources in the late afternoon and evening.

Although caffeine is not considered to be addictive, it can be habit forming. Anyone interested in reducing caffeine intake may find it helpful to:

• Cut back gradually. For some, abruptly going cold turkey can temporarily cause headaches, drowsiness and difficulties with concentration. Eliminating one cup a day will help avoid this problem.

• Substitute herbal tea, decaffeinated tea or coffee, hot cider or water for caffeinated drinks.

• Mix a half-cup of regular coffee with a half-cup of decaffeinated coffee.

• Brew tea for a shorter time to reduce caffeine content.

• Read soft drink and medication labels carefully. Nearly 75 percent of soft drinks and certain over-the-counter pain relievers contain caffeine. Caffeine will be listed in the ingredient list if it's present in the product.