Coffee: A User's Guide

You need to finish writing a 75-page business plan. You need to wake up at 5 a.m. You need to stay alert through a three-hour meeting.

You need coffee.

You and everybody else. An estimated 90% of all adult Americans get their daily buzz from caffeine, and for most of them the delivery vehicle of choice is coffee.

Yes, caffeine is a drug. When ingested, it triggers mostly pleasurable chemical reactions in your body. Sip some coffee, and caffeine increases your brain's level of dopamine, a neuro- transmitter that activates your brain's pleasure center. (Heroin and cocaine do that, too.) Caffeine also speeds your brain activity by supplanting adenosine, a compound your body produces when you're tired. In response, your pituitary gland releases hormones that kick up production of adrenaline, making you ready to fight or take flight. As a result, caffeine dilates your pupils, speeds your heart rate, constricts your blood vessels, raises your blood pressure, and tightens your muscles. Feeling better now?

You can satisfy your caffeine jones with tea, cocoa, chocolate, some soft drinks, energy bars, and pep pills -- but coffee is quicker by far. A six-ounce cup o' joe delivers up to 180 milligrams of caffeine, and nothing else comes close. The same amount of tea, steeped for a full five minutes, contains just 100 mg. Six ounces of Jolt cola packs only 35 mg of caffeine, and the same quantity of hot chocolate, a mere 10 mg. And unlike hot chocolate, black coffee is a dieter's dream: absolutely no calories or fat.

If efficiency is your game, gulp espresso. Six ounces of the inky brew will rev you up with 300 mg of caffeine -- enough, technically, for an overdose. Mercifully, a typical coffee bar's "solo" espresso fills only two ounces, for a manageable 100 mg of caffeine.

Tea is a different beast. It contains not only caffeine but also theophylline, a compound that can ease the symptoms of a cold. But perhaps the real differences are cultural. The entrepreneurs behind Republic of Tea, Ron Rubin and Stuart Avery Gold, say tea is a "consciousness-altering substance," while coffee is merely for "speeding up and losing sight." Maybe. For most coffee drinkers, however, tea is reserved for those times when we're under the weather, eating in Chinese restaurants, or pretending to understand Zen.

Any way you pour it, coffee should be handled with care. Drink too much -- as little as two cups -- and you may feel restless, nervous, unable to sleep, even sick to your stomach. "Coffee roasts your insides," wrote Balzac, who knew. Drink really too much -- a ridiculous 50 cups -- and you can actually kill yourself.

But science gives coffee drinkers little reason to worry. Despite persistent suspicions that caffeine could cause cancer, birth defects, and infertility, evidence from the research labs remains inconclusive. If you really want to scare yourself, Caffeine Blues: Wake Up to the Hidden Dangers of America's #1 Drug awaits. But it's 320 pages long -- better make that latte a double.

The Inc Life

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