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NSC Knowledge Center Safety Article Archive
Watch Your Caffeine Intake
A cup of coffee in the morning or during work hours has become engrained in today’s culture.
According to the Mayo Clinic in Rochester, MN, 9 out of 10 Americans consume some type of caffeine
on a regular basis, making it the most popular behavior-altering drug.
But how safe is caffeine? Several studies have been conducted, some of which cite the health benefits
while others cite the ill effects of ingesting the drug. It can increase alertness and is rarely fatal, but
Food or Drug?
“Part of the problem is that people do not think of caffeine as a drug, but rather as a food product,”
said Danielle McCarthy, M.D., a researcher at Northwestern University in Evanston, IL.
Caffeine is a central nervous system stimulant that in moderate doses can increase alertness,
according to Johns Hopkins Medicine in Baltimore. However, caffeine also can cause nervousness,
increase the time it takes to fall asleep and reduce fine motor coordination.
Some evidence points to caffeine carrying a risk of physical dependence, complete with withdrawal
symptoms such as headaches, fatigue and muscle pain after only a day, Johns Hopkins researchers said.
According to health experts, between 200 and 300 milligrams of caffeine – about two to three cups of
coffee – is not harmful. Some studies have even shown coffee to have health benefits, including one
published in the American Journal of Clinical Nutrition (Vol. 85, No. 2) that concluded habitual intake of
caffeinated beverages protects against heart disease deaths among the elderly.
But going over the recommended 300 milligrams of caffeine daily can have adverse effects. According
to the Mayo Clinic, more than 500 milligrams a day could cause irritability, nervousness, anxiety,
insomnia, headaches and diarrhea. It’s not hard to go over the suggested caffeine-intake limit: One
16-ounce cup of Starbucks coffee has 259 milligrams, according to the Mayo Clinic, so just two cups
equals what the clinic calls “excessive caffeine.”
Abuse and Overdose
The lethal caffeine level is extremely high – the equivalent of 80 to 100 cups of coffee in one sitting. But other
sources of caffeine, like pills or supplements, can lead to illness if abused or combined with other drugs.
Caffeine pills and supplements have been popularized by college students, truck drivers and
shiftworkers, all of whom use the drug’s boost to stay awake longer and fight off fatigue.
A recent study by researchers at Northwestern University examined three years’ worth of calls to the
More than 250 cases came into the center reporting medical complications from caffeine supplements,
of which 31 were patients requiring hospitalization (20 of whom were admitted to the intensive care
unit). Study researchers focused primarily on caffeine medications or dietary supplements, not on
In 186 of the cases, caffeine abuse was reported as the lone component. In 81 cases, caffeine was
National Safety Council ● 1121 Spring Lake Drive ● Itasca, IL 60143 ● 800.621.7619 ● [email protected]
NSC Knowledge Center Safety Article Archive
reported as the lone component. In 81 cases, caffeine was combined with other pharmaceutical
products, which was significantly associated with hospitalization, according to the study. The
average age of the victims was 21. “We want people ingesting caffeine pills and supplements to
know that caffeine is a drug, and overuse is potentially harmful, especially when mixed with other
pharmaceuticals for euphoria. There is a trend in the pro-drug culture toward promoting legal
alternatives to illegal drugs, and it can be very harmful,” researcher McCarthy said.
Energy drinks, which contain large doses of caffeine, also have become popular recently, as has
combing them with alcohol. But experts warn that doing so increases the risk of dehydration while the
caffeine can mask how intoxicated a person actually is. Curbing Caffeine
If you believe you might be too dependent on caffeine, it might be time to reduce your intake.
The Caffeine Awareness Alliance – a Royersford, PA-based nonprofit organization that seeks to educate
and reduce the harm associated with caffeine abuse and addiction – offers several tips to reduce
• Plan to quite on a Saturday or Sunday, as most people drink less coffee on the weekend.
• Gradually reduce the amount of coffee you consume.
• Substitute caffeine-free beverages.
• Prepare for withdrawal symptoms.
The Mayo Clinic also recommends checking the amount of caffeine in the food, beverage and over-
the-counter medications you consume. Brew tea for less time – or drink herbal tea – and switch to
caffeine-free versions of pain relief and headache medications. Copyright 2007 * National Safety Council * All Rights Reserved.
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