What
is caffeine?
Caffeine
is a central nervous system stimulant. It's one of the most popular
drugs in the world, consumed by up to 90% of people in the world
in one form or another, but mostly in beverages. It is a naturally
occurring substance found in plants like cocoa beans, tea leaves,
and kola nuts.
What
are the effects of caffeine?
Caffeine's
strongest effects are felt for about an hour after taking it, but
some effects usually last 4 to 6 hours. Caffeine causes increased
neuron firing in the brain which the pituitary gland perceives as
an emergency and therefore causes the adrenal glands to release
adrenaline. Caffeine also increases dopamine levels -- the neurotransmitter
that is affected by drugs like amphetamines and heroin. Obviously,
it does this on a much reduced level from those drugs, but this
may be the source of caffeine's addictive quality.
While
caffeine is mildly addictive, it has not been shown to have a direct
link with any serious health risks. Still, anyone who's been up
all night after drinking too much coffee can tell you that caffeine
can affect a person's mood and sleep pattern. Here are some of the
frequent effects of caffeine:
Caffeine
is a diuretic. Caffeine prompts the body to lose water through
urination. This can lead to dehydration and is the reason that
caffeinated drinks are not a good idea when working out or doing
other activities that require fluids. In fact, it is suggested
that you add 8 ounces of water for every cup of coffee you drink.
Caffeine
can cause you to feel jittery, skittish, restless, excitable or
anxious. It can temporarily speed the heart rate. If you're feeling
stressed out, then a cup of coffee can exacerbate, rather than
help, this feeling. Too much caffeine can hurt a person's ability
to concentrate, making it difficult to study.
Caffeine
can cause insomnia. It can be very hard to fall asleep when you
take a lot of caffeine. This is especially true if you take it
at night, but is also true of higher doses earlier in the day.
Caffeine
at high doses can cause headaches.
Some
caffeinated beverages can have other health effects. For instance,
the acid in coffee can upset the stomach, and coffee (though not
the caffeine in it) can worsen ulcers, raise blood pressure and
blood cholesterol, and speed up the heart rate, increasing the
risk of heart disease.
Caffeine
can have negative effects on pregnant women or on women who would
like to become pregnant including an increased risk for difficult
conception and miscarriage. Caffeine is transmitted through the
placenta and through breast milk to the baby. Therefore, if you're
pregnant or thinking about becoming pregnant, the FDA recommends
that you stop taking caffeine or cut back to 1 cup per day.
How
much caffeine am I having?
In the U.S., the average person drinks 200 milligrams
a day (about two 8 ounce cups of coffee). Check out the list below
to see how much you're having.
How
do I cut back on caffeine?
Remember
that caffeine is addictive. If you feel like you can't get going
in the morning, feel overtired during the day from not having caffeine,
or get headaches when you try to stop taking caffeine regularly,
these are signs of dependence.
If you're
having trouble sleeping, feel like you are consuming too much caffeine
or you don't like the effects of caffeine on your body, here are
some suggestions for quitting or cutting back:
Switch
to decaffeinated beverages, or to a mixture of decaffeinated and
regular coffee.
Reduce
the number of caffeinated drinks you have every day. If you have
coffee in the morning and a Coke in the afternoon, try skipping
the Coke and replace it with water or juice.
Brew
tea for a shorter time. The less time you brew it, the less caffeine
it will contain. Try herbal teas which usually don't contain caffeine.
Watch
out for soft drinks and energy drinks like Red Bull which can
contain added caffeine. This will be listed on the label.
If
you are trying to quit and feel yourself getting a headache, you
can try having a small amount of caffeine to alleviate the headache.
For some people, this helps keep up the momentum to quit.
Know
what's in over-the-counter medications. These can contain large
doses of caffeine, too.
Drink
water or non-caffeinated drinks when you're thirsty. Remember,
caffeinated beverages will only add to your body's dehydration.
What
other stimulants contain caffeine?
Some herbal stimulants can contain naturally occurring
caffeine, especially guarana and mate. This caffeine can have the
same effects as coffee or tea. Be careful of energy drinks, which
can contain up to 80 mg of caffeine and other stimulant ingredients.
See our web page on Energy
Drinks for more information.
This link has medical and chemical information on
caffeine as well as the breakdown of how much caffeine is in medications
like Anacin, Vivarin and Dexatrim.
This link has several brief articles on caffeine, including Cutting
Down on Caffeine, Chocolate: Facts and Fiction and Straight Facts
About Beverage Choices.
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