These Drinks Are Sneaky Sources of Caffeine

Of all the substances humans use to augment, alter, suppress, and avoid various aspects of our existence, caffeine is one of the most amazing. Is it disturbing to realize that you literally can't function as an adult without a jolt of caffeine? Sometimes, sure. But for most of us, caffeine is a relatively harmless pick-me-up with very few downsides.

Except when it comes to sleep. Caffeine's a pretty effective stimulant, and it can negatively impact your sleep if you have too much of it. Studies have shown that substantial amounts of caffeine even six hours before you go to bed can make it harder to fall asleep and diminish the quality of the sleep you do get. For those of us who have a little trouble sleeping, the solution is usually to stop taking in caffeine at a certain point during the day--which would be a great strategy, were it not for all of the surprising places you find caffeine these days.

How much is too much?

We're all different, but most humans can consume about 400 milligrams of the stuff every single day without measurable harm; for reference, a standard eight-ounce cup of coffee has close to 100 milligrams of caffeine, most energy drinks hover around 70-75 milligrams, tea has close to 50 milligrams, and colas have about 22 milligrams (there are, of course, examples of each that have a lot more or a lot less).

When we think of caffeine we think of the obvious culprits: Coffee, tea, soda, chocolate, and anything that uses those things as an ingredient. When it comes to sleep, a few milligrams of caffeine in a cookie or a bowl of cereal probably won't disrupt your sleep--but if you're having trouble falling or staying asleep, check to see if you're unwittingly dosing yourself with caffeine with some of these surprisingly caffeinated foods.

Pain relievers

Caffeine is often used to magnify the effect of pain relievers like acetaminophen (the main ingredient in Tylenol). The effective dose of caffeine in pain relievers is typically above 100 milligrams (though some pain relievers that include caffeine use less), so popping a few pills before bedtime to ease a stiff back or a headache so you can sleep can actually be counter-productive, since you might be taking in the equivalent of a coffee cup's worth of caffeine.

Some orange sodas & root beers

If you're like me, you grew up thinking the rule of thumb for caffeine and soda was that colas = caffeine, citrus = no caffeine. But, surprise! Some orange-flavored sodas do in fact contain caffeine. Sunkist Orange Soda, for example, has 19 milligrams of caffeine per 12 fluid ounces. That's not a huge dose, but if you drink a couple of sodas a few hours before bedtime, it adds up. Similarly, while most root beers are caffeine-free, some brands, like Barq's, contain about 22 milligrams of caffeine per 12 ounces. In other words, it pays to always check before you crack that can open.

Some flavored waters

If you're someone who hates drinking plain old water and always opts for a flavoring to jazz it up, you might assume that there's no caffeine in sight. And you're probably right--although some flavored (and unflavored) water brands advertise added caffeine, they're easy enough to avoid. The one way you can get tripped up in the flavored water arena is when euphemisms are employed. If the name of your flavored water includes terms like "energy" or "boost," double-check the ingredients list.

You can also get a clue from those ingredients--just as coffee-flavored energy bars typically have a lot of caffeine, flavored waters including coffee or teas in their formulation can pack a punch even if they're not advertised as caffeinated. For example, the AHA brand of flavored waters has three products that include black or green tea in their formulation, resulting in a dose of about 30 milligrams of caffeine. That's not a lot of caffeine, but it adds up.

Green tea

Green tea doesn't sound as serious as black tea, but that doesn't mean it's caffeine free. Your average green tea contains about 25 milligrams of caffeine per eight ounces (specific types of green tea or formulations using it have varying amounts, ranging from 12 milligrams to 75 milligrams or more). Bottom line: If you're hankering for a soothing cup of green tea before bedtime, double-check before you brew.

Kombucha

Despite being a tea, most people don't associate kombucha with caffeine. But most kombucha contains a small but notable amount of caffeine, ranging between eight and 14 milligrams. That's probably not enough to ruin your night by itself, but if you've already consumed a lot of caffeine during the day, it could be enough to push you over the edge. Similarly, if you enjoy a few too many cups before turning in, you might find yourself staring at the ceiling for a few hours.

Sleep is essential to good health, so avoiding anything that can inhibit a good night's rest is essential. With some products, that requires a little detective work.