What is caffeine?
is a naturally occurring substance found in cocoa beans, kola nuts and
What are the sources of caffeine?
The main source of caffeine for most Americans is coffee. Caffeinated
coffee has the highest caffeine content (85mg per 8 ounce cup) of all
beverages. Caffeine is also found in teas (47mg per 8 ounce cup) and
chocolate. The caffeine content of tea increases with the length of brewing
time. Caffeine is added to many sodas (37 mg per 12 ounce can), energy
drinks, and nonprescription medications. In the United States, if caffeine
is added to a food or medication, it must be listed as an ingredient
on the label. Although the caffeine added to one serving of beverages
may seem relatively low, the caffeine can add up if a large number of
servings are consumed each day. Click here for information about the caffeine content of foods and medications (Center for Science in the Public Interest, 2007).
What does caffeine do in the body?
Small to moderate amounts of caffeine act as a mild stimulant by temporarily
increasing both the heart rate and blood pressure. Caffeine may affect
a number of other body systems and the response to it may vary depending
upon the amount consumed and an individual's caffeine sensitivity.
Does moderate caffeine intake affect bone health?
There may be a small decrease in calcium absorption associated with moderate
caffeine consumption (up to 300mg of caffeine per day). In addition,
there is minor increase in calcium loss in the urine for several hours
after caffeine consumption. However, when the recommended amount of
calcium is consumed, the small decrease in calcium absorption and increase
in calcium output caused by moderate caffeine intake can easily be offset.
For example, the amount of caffeine in a cup of coffee can slightly reduce
calcium absorption but adding a few tablespoons of milk can easily make
up for it.
What happens when caffeine is consumed in excess?
Greater bone loss and higher fracture rates have been associated with
some but not all studies of populations (mostly postmenopausal women)
consuming high caffeine intakes. However, caffeine intake may be a problem
only if calcium intake is inadequate or if there are other detrimental
lifestyle factors. It seems that much of the harmful effect of caffeine
is not due to the caffeine itself, but is more due to the fact that caffeine-containing
beverages are often consumed instead of calcium-rich beverages like milk
and calcium-fortified alternatives. The evidence suggests that it is
wise to avoid consuming more than moderate amounts of caffeine (more
than 300 mg per day) and to make sure that calcium intake is adequate.
Moderation of caffeine intake is usually best for most!
Although caffeine sensitivity varies greatly among individuals, a moderate
intake of caffeine (up to 300 mg per day) is considered to be relatively
harmless for most people. On the other hand, caffeine should be avoided
or strictly limited by people with ulcers, those who are hypersensitive
to caffeine, and by pregnant women and nursing mothers. All individuals
especially those with high blood pressure, any medical condition, or
those with caffeine sensitivity should discuss the intake of caffeine
with their doctor or healthcare provider.
If you need or desire to reduce your caffeine intake, the following
suggestions may help:
- Drink decaffeinated coffee or dilute regular coffee by mixing it
with decaffeinated coffee
- Drink decaffeinated tea or caffeine-free herbal teas
- If you prefer regular tea, brew tea for shorter amounts of time
- Read the labels of your medication; one dose of over-the-counter
medications can contain the equivalent of 1 to 2 cups
- Be aware of what you drink. Did you know that certain citrus-flavored
sodas have more caffeine than colas?
If you consume caffeine, be sure to get enough calcium!
If you consume caffeine, it is important to get the amount of calcium recommended for you each day. The first step is to estimate
the calcium in your diet to find out if you are getting the
amount recommended. If your calcium intake is less than the amount recommended, there
ways to increase the calcium in your diet. Some individuals need
or prefer to take a calcium
supplement in order to get the recommended amount of calcium on a daily basis. If you
think that you need a calcium supplement, it is suggested that you discuss
your individual needs with your doctor or healthcare provider.