Other issues of Nutrition Advisor

What about caffeine?

Whether you enjoy waking up to a fresh pot of coffee, washing your lunch down with a cola or relaxing at night with a cup of tea, these beverages have one thing in common. . .caffeine. This naturally occurring substance is found in the leaves, seeds and fruits of more than 60 plants. Even though it is one of the most widely studied ingredients, much controversy and misperception about caffeine continue to brew.

Everything in moderation. . .
Extensive research has been conducted on the health aspects of caffeine consumption, and most governing bodies, including the U.S. Food and Drug Administration (FDA) and the American Medical Association (AMA), have one comment in common-moderation. But when it comes to caffeine, how much is too much?

Enough is enough!
Caffeine is a stimulant and can temporarily boost energy levels, fight fatigue, increase heart rate and elevate blood pressure by acting on the central nervous system. People differ greatly in their sensitivity to caffeine. Some can drink several cups of coffee, tea or cola and not feel any effects, while others feel the influence after only one serving. The key to caffeine, like most other foods, is moderation. Moderate caffeine consumption is considered to be about 300 mg a day. The amount varies among beverages.

Caffeine content of various foods

*The range is due to different brewing methods, brand, plant variety, etc.

Source: International Food Information Council

Coffee is the chief source of caffeine in the U.S., but soft drinks and teas are a close competitor. Cola isn't the only soda with caffeine. Some citrus-beverages contain even more! Be sure to check the ingredients.

What's the connection between caffeine and health?
Pregnancy
Although caffeine has not been shown to adversely affect reproduction in humans, the FDA still advises pregnant women to consume caffeine in moderation. The effects of caffeine on conception are controversial and research findings are inconclusive. During pregnancy there is a tendency for an increased sensitivity to caffeine, and since caffeine can pass through the placenta and breast milk, most experts advise going easy on caffeine during pregnancy and while breastfeeding.

Osteoporosis
An adequate calcium intake remains crucial for bone growth and development. While excessive caffeine intake may increase calcium excretion, studies to date show no link between osteoporosis and caffeine if caffeine is consumed in moderation and adequate calcium is included in the diet. By adding low-fat milk to coffee and including plenty of calcium in the diet, the impact of caffeine on bone density is minimal.

Heart disease
Studies do not link caffeine to the development of heart disease. However, since caffeine can elevate blood pressure, those with hypertension should discuss the use of caffeine with their physician.

Consuming caffeine is a personal choice and safety is not an issue if you enjoy it in moderation. If you do decide to reduce your caffeine intake, make sure to do it gradually. If you cut back too quickly, you may experience withdrawal symptoms, such as headaches and irritability. If you're accustomed to a large mug of coffee to start your day, try mixing half regular and half decaffeinated. Also make sure to drink plenty of water since caffeine can gradually increase water loss.

The Yale-New Haven Nutrition Advisor is created by registered dietitians and dietetic interns who staff the Nutrition Clinic at Yale-New Haven Hospital. For information, contact the Nutrition InfoLine at (203) 688-2422.

For more information visit these sources:

• Questions and answers about caffeine and health, International Food Information Council
• Everything you need to know about caffeine, International Food Information Council
• Caffeine: Hype or hyper?, American Dietetic Association
• Caffeine, Neuroscience for Kids, Dr. Eric Chudler, Univ. of Washington

Other issues of Yale-New Haven Nutrition Advisor:

• Nutrition month
• Eating for heart health
• Outstanding antioxidants
• Tea time: go for the green
• Microwave mania
• Coffee drinks
• Nuts are good for you
• Mom was right about breakfast
• A glass of red wine a day keeps the doctor away
• Let's get physical, summer activities

Last revised: March 10, 2005 (jj)

Home page URL: http://www.ynhh.org

All information is intended for your general knowledge and is not a substitute for medical advice or treatment for specific medical conditions. You should seek prompt medical care for any specific health issues and consult your physician before starting a new fitness regimen.