5 Eye-Opening Facts About Caffeine

We're a nation hooked on caffeine — and that's a good and bad thing.
We're a nation hooked on caffeine — and that's a good and bad thing.

In his new book, Caffeinated: How Our Daily Habit Helps, Hurts, and Hooks Us, journalist and environmental scientist Murray Carpenter investigates the world's most widely used, highly unregulated stimulant: caffeine. He visits Mexican cacao groves, a Chinese synthetic caffeine plant, coffee fields in Guatemala, Federal Drug Administration (FDA) representatives, and U.S. energy drink factories. He delves deep into scientific studies on the physiological and psychological effects of caffeine on the body -- and uncovers some pretty startling stuff.

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Here are a few facts that really stood out:

1. We Drink Less Coffee Today
We think of our culture as hooked on coffee, but actually our grandparents were far more caffeinated than we are. Coffee consumption peaked shortly after World War II, when Americans were consuming 46 gallons a year, or about 20 pounds of beans per person. Today, the average American drinks around 23 gallons of coffee a year.

2. We Are Easily Addicted
The average person needs to consume about 30 milligrams of caffeine to feel its rousing effects, and just 100 milligrams a day (the amount in a small cup of coffee) will hook most people. About 80% of Americans drink caffeine daily, and if the caffeine supply chain was disrupted, 125 million Americans would be hit with abysmal headaches, and 32 million would experience "clinically significant distress or functional impairment" from withdrawal.

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3. No Cup of Coffee Is Created Equal
There isn't a standard for the amount of caffeine in a cup of coffee -- and that includes within a single brand. A 16-ounce cup of coffee from Starbucks has more than twice the amount of caffeine (330 mg) than the same size from Dunkin' Donuts (143 mg). The Starbucks cup of coffee is almost four and a half espressos (which average 75 mg per 1.3-ounce shot). Also, a cup of coffee from a particular coffeeshop may differ in caffeine content from day to day, depending on who is making it, how, and from what.

4. Caffeine in Our Food Is Not Regulated
The FDA does not require that beverage manufacturers include caffeine content on their products' labels. In fact, there is a dual-regulatory system for caffeine: The FDA regulates it when it's marketed as an over-the-counter medication but has taken a more "hands-off" approach to its presence in beverages. However, Michael Taylor, the FDA's deputy commissioner for foods and veterinary medicine, is carrying out an extensive investigation on the safety of caffeine in food products and energy drinks. He's particularly concerned about products marketed to children and adolescents.

Related: A New, Disturbing Fact About How Sleep Affects Your Brain

5. Caffeine Can Be Good...And Bad
With just a small amount of caffeine, your brain, blood vessels, muscles, and digestion become more efficient. It can heighten your athletic ability, alertness, and cognition. With an excess of caffeine, you may experience anxiety, panic attacks, disrupted sleep, and even cardiac arrest.

- By Betty Gold

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