Exactly How Much And How Often You Should Be Drinking Coffee

Two cups or six? A certain amount of coffee is good for you, but too much of a good thing could undo the benefits.

If you treat your daily caffeine jolt as though it were a sacred ritual, you’re not alone.

According to a Zagat survey earlier this year, 87% of Americans consume at least one cup of coffee a day. Fifty-five percent even admitted to being addicted to their daily cup.

While caffeine in moderate doses can increase mental alertness, fight off headaches, and even help prevent diseases such as Alzheimer’s, type 2 diabetes and certain cancers, worshiping your neighborhood barista can have some serious negative side effects. You might want to read before downing your sixth cup of coffee.

Caffeine is the most widely used psychoactive stimulant, targeting the central nervous system and heightening your brain’s feeling of alertness. According to the FDA, 400 mg per day of caffeine (that’s about four cups of coffee) is a safe amount of caffeine for healthy adults. But too much caffeine—500 to 600 mg—can be dangerous, causing restlessness, tremors, irritability, insomnia and stomach upset.

The problem is, most of us don't just consume caffeine in coffee, but in chocolate and soda as well. Caffeine is now being added to gum and other previously caffeine-free treats such as jelly beans, meaning it’s not difficult to hit your daily maximum even without making a double Starbucks run.

For many of us, it may be hard to imagine how to get through our day without our daily cup of coffee. While caffeine’s stimulant effects will vary from person to person depending on a number of factors including body mass index, medication use, and existing health conditions such as anxiety disorders; knowing how much caffeine you consume daily can be the key to optimizing its positive benefits, heightening your concentration and mental alertness when you need it and decreasing it when it’s time to rest.

How much caffeine is in my coffee?

While four cups of coffee may seem high, keep in mind most coffee shops serve beverages larger than 8 oz. A Starbucks Grande (16 oz.) contains 330 mg of caffeine while a 20 oz. Venti contains 415 mg—just above your daily maximum.

The most recent annual National Coffee Association of USA’s National Coffee Drinking Trends showed the popularity of specialty coffees and espresso-based drinks such as cappuccinos and lattes is on the rise, jumping from 13% last year to 18%. But that single 1 oz. shot of espresso alone contains 64 mg of caffeine.

Moderate caffeine intake may be key to optimizing its benefits

Although many of us enjoy a large caffeine jolt to jumpstart the morning, A landmark 2004 study by researchers at Harvard Medical School on the best caffeinating strategies revealed small, frequent doses of caffeine—about 2 oz. (or a quarter cup of coffee) every hour—is the best strategy to stay alert and awake throughout the entire day.

Caffeine reaches its peak level in the blood stream within 30 to 60 minutes of consumption and can remain elevated for three to five hours before you begin to crash. Optimizing caffeine’s stimulant effects all day long may mean swapping your ginormous coffee-addict mug for a teacup size cup several times a day.

Track your intake

If you’re concerned about your daily intake, you may want to consider downloading caffeine tracking apps to help you determine the optimal time for a caffeine jolt. Caffeine Zone 2 (free for iOS), developed by the ACS Lab at Penn State University, allows users to note the amount of caffeine consumed and tracks how long the stimulant will remain elevated in your bloodstream. A graph shows how your caffeine intake will affect your alertness level and your sleep.

If you punch in another cup while you’re still “in the zone” (or at your optimal level of awareness)—which the app determines as having between 200 and 400 mg of caffeine in your bloodstream—it will give you a warning that the drink won’t do you any good. Jawbone’s Up Coffee (iOS) or Caffeine Tracker (for Android) provide similar tracking services.

Keep up with #coffeeweek at Fast Company

[Image: Flickr user Thomas Angermann]

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9 Comments

  • If it this article holds any truth to it; I shoudn't and couldn't be writing this. Over 25 y. Expressos at a rate of 1 kg of beans each 5 days and none of the symptoms (?). Never had a stomach problem (well, over 20 years ago I recall one episode of "Kissing Ulcer" due to "Helicobacter Pylori", done after 10 days on antibiotics and cokes). Moreover I have Chronic Asymptomatic (even with coffee) Hiatal Hernia.

    Stop letting "Conventional Wisdom" tell you what to do or not, come to terms with the fact you'll die and start enjoying life.

    PS. Yesterday, Conventional Wisdom was a flat Earth at the centre of the universe, ingesting mercury was as healthy as it was neglecting to sanitize between patients. Today, massive eavesdropping and surrendering your rights to the TSA to take a plane both in the name of a delusory security is just right. BTW "Another" plane (2° for Air Malaysia) was put down, this one over Ukraine. I'll rather die for my rights than live deprived of them.

  • Zack Oliver

    Starbucks caffeine is 20 mg/ounce in coffee and 75 mg/ounce in espresso. So 4 cups of coffee gets you over that dreaded 600 mg limit.

    People SAY espresso is stronger...and sure, per ounce it is. But a venti espresso drink gets 2 shots--that's only 150 mg of caffeine.

    A Starbucks Americano (basically an Espresso coffee) get you 4 shots in a Venti size--that's only 300 mg of caffeine.

    I've always liked espresso better because coffee drags me kicking and screaming to alertness, but espresso invites you there. I hardly have caffeine anyway, though, except for in teas. I never feel better than when I get to bed at 930 and wake up around 6. That's the stuff!

  • Devon Nullz

    This is almost entirely bunk. People obsess over a 0.000002% increased risk of this or that ailment, thinking they can grant themselves immortality with just the precise food choices. It's a fool's game.

    What's also a fool's game is treating everything we eat or drink as if it must be either medicine or poison. When what we eat and drink becomes so over-analyzed into mechanics, we've removed any and all joy or pleasure from our lives. We no longer drink coffee because we like it, but because it fits a regimented prescription falsely imprinted in our wishful minds.

    Decades and billions of dollars wasted on coffee-related medical research later, let's face facts: coffee is pretty much irrelevant to our health. We even have 1,000 years of epidemiological evidence to back it up. And yet we keep beating this dead horse of coffee and health research, pretending like some great discovery is just around the corner. Meanwhile, we neglect medical research on other concerns.

  • Zack Oliver

    The point of the article is that people, in general, are ignorant that excess caffeine is a detriment to physical and mental well-being. The examples used are perfectly within the parameters of my experience when serving coffee to people. They think caffeine has no effect on them besides 'waking them up.' It really just stimulates adrenaline production and gets your stress hormones going. For someone like me, who has a little anxiety, that much extra stress hormone puts me on edge for a few hours until it works through my system. I can't imagine what people with worse stressors than mine are doing

  • Maryann Pearson

    Wow, you must have been reading my mind :>) i feel the same way about pizza, croissants, salt, a really good hamburger, mayonnaise (i love mayonnaise) and anything else i have a serious craving for. I also crave avocadoes, mangoes and spinach, but hey we don't need to worry about those yet. We don't need research to know that 5 hamburgers a day is probably not so good...has everyone totally given up on trusting their instincts and listening to what their own body is telling them?

  • Mark Johnson

    I'm excited about getting my Vessyl for keeping a track of things like caffeine intake