How Much Caffeine is Too Much?

Imagine this: you're feeling jittery, restless and anxious. Then, your day goes to the dumps when you experience an energy crash and a pounding headache to go with it. Why would you willingly consume something to cause this?

Some of us start the day just short of punching a mocha blast IV in our arm. Many of you are somewhat immune to its effects, while others keep upping the ante until they receive the benefits they desire. The focus use to be centered solely on our morning savior, coffee. Anyone mentions caffeine and your thought process goes directly to everyone’s most popular morning pick-me-up. But now there’s a lot more buzz about the stimulant itself—from studies about how it affects health to new super-octane beverages that pledge to give you a boost when you need it. There are claims that it improves athletic performance and even helps you lose weight. Caffeine has even made the leap to pancake syrup, gum and soap. (It’s absorbed through the skin, according to soap manufacturers.) As products proliferate and the caffeine gauge edges higher, a question begs to be answered: How much caffeine can (or should) we handle?


Say It Ain’t So, Joe!
Caffeine is a nervous system stimulant that occurs naturally in over 60 plants. When ingested, it blocks adenosine, a chemical that slows brain activity. The body then releases adrenaline, which in turn results in alertness and heightened concentration. The effects peak in 30 to 60 minutes, then taper within several hours. Caffeine does not accumulate in any part of the bloodstream or body and is normally excreted within several hours following consumption.

The average adult consumes about 200 milligrams of caffeine daily, while the average child consumes one-quarter of that amount.

Most health care professionals consider 250 to 300 milligrams (equal to about three cups of coffee) to be a moderate daily dose. Go beyond that and you may be shaking in your penny loafers and have trouble concentrating or sleeping. You also could temporarily suffer elevated blood pressure or an irregular heartbeat.

People differ greatly in their sensitivity to caffeine; some individuals can drink several cups of coffee, tea, soft drinks, or energy drinks within an hour and notice no effects, whereas others may feel stimulating effects after one serving.

There’s probably no reason for alarm if you consume moderate amounts of caffeine, though. Research shows that the danger and risks of caffeine seem to be very minimal, even when consumed in somewhat larger amounts. Those with heart disease and high blood pressure should, however, watch and limit their intake, as well as pregnant and lactating women.

A Wired World
During the last decade, the popularity of super-caffeinated energy drinks like Red Bull, Vault and Full Throttle has increased dramatically. According to market statistics, sales grew an enormous 700 percent between 2000 and 2005.

The actual amount of caffeine in energy drinks is generally lower than a weak cup of coffee, but certainly more than the average soft drink. Energy drink manufacturers usually, however, pair the ingredient with substances such as sugar, herbal stimulants (guarana and ginseng) and taurine (an amino acid) for an extra punch and marketing edge.

Though some energy drinks are marketed to athletes, most active, fit adults do not need the extra calories they deliver. And as for additives such as taurine, eating a hard-boiled egg or a handful of nuts will provide you with a better-balanced protein. Energy drinks should generally not be used while exercising as the combination of fluid loss from sweating and the diuretic quality of the caffeine can leave the user feeling dehydrated.

Energy drinks are not necessarily detrimental to your health, but they shouldn't be seen as ‘natural’ alternatives either. Some of the claims they make, like, "improved performance and concentration," can be misleading. If you think of them as highly-caffeinated drinks, you'll have a more accurate picture of what they are and how they affect you.

That’s not to say caffeine can’t enhance performance and alertness. Even small doses have shown to provide these benefits. However, consistent use of caffeine can hamper the beneficial results due to decreased sensitivity.

The Brain Pain
Caffeine has surprisingly been shown to cure and cause headaches. Caffeine and caffeine-containing medications often improve symptoms for persons who are feeling a jackhammer on their head. However, you can also suffer from headaches if you abruptly quit consuming caffeinated products.

During a tension headache (exhibiting by dull, constant pain), blood vessels dilate, meaning they open wider. Caffeine causes the vessels to constrict, or become narrower. This process allows caffeine, sometimes in combination with ibuprofen, acetaminophen or aspirin, to help a headache subside.

Caffeine withdrawal headaches on the other hand are characterized by a throbbing sensation caused by rebound dilation (re-opening) of the blood vessels and generally occur multiple days after consistently high caffeine consumption. To cure or prevent these types of headaches, you may need to adjust your daily caffeine intake.

Switch Your Fix
If you are a constant caffeine drinker and would like to either wean off the addicting stimulant or “re-sensitize” yourself to a lesser dose, controlled research has shown that the maximal nervous system response to caffeine is regained within three weeks of abstinence—with re-sensitization becoming apparent in as little as four days. But don't forget that this may cause withdrawal headaches or other side effects and additionally will require the removal of all caffeine from your diet. (Abstaining from coffee while still chugging soft drinks or energy drinks on a regular basis will unfortunately do little to help you re-sensitize.)

An immediate switch to the same amount of decaffeinated coffee or tea will most likely produce symptoms of caffeine withdrawal—irritability, headache, inability to work effectively, nervousness, restlessness and exhaustion. If you currently drink more than three cups, cut down by a minus 1 cup per day every three or four days until you are down to three cups per day. This will help reduce the symptoms of caffeine withdrawal. While you are cutting down, you can replace one cup of regular coffee with one cup of decaffeinated coffee. Sometimes it is hard to keep track of how many cups of coffee you drink per day, but try and limit yourself to one cup of caffeine-containing coffee per meal. If you want more coffee, switch to decaf.

It may also be helpful to keep track of how much caffeine you regularly consume on a weekly basis to see where and how you need to cut back. Just remember to do-so slowly and be patient with yourself.

Individuals who work alternating schedules sometimes have the problem of needing to adjust their schedules and often their use of caffeinated beverages to stay awake. It may be helpful to eat a protein-rich meal before work to help you stay awake, as meals higher in carbohydrates (with lots of breads, fruits and dairy products) may make you sleepier.

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/tea.
• 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 period of
time. The less time you brew it, the
less caffeine it will contain. Try
herbal teas, which usually have none.
• Watch out for soft drinks and energy
drinks that contain additional
caffeine. Unfortunately, this will not
necessarily be listed on the drink 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. This may be
helpful for your headaches, but
may not aid in your caffeine-wean.
• Drink water or non-caffeinated
drinks when you're thirsty. Caffeinated
beverages help hydrate your body
as much as your caffeine-free
alternatives.

Lee T. Murphy, MS-MPH, RD, LDN