| July 5, 2012

Overworked and sleep-deprived, more people are using caffeine as an energy crutch than ever before, experts say. That's not all bad: In fact, 250 milligrams of caffeine per day — that's two to three cups of joe — wakes up the brain, improves concentration, relieves stress and may also help you live longer. But if intake is turning into addiction, you may notice side effects including dehydration, trouble sleeping, anxiety, an upset stomach and even problems during pregnancy.

If you're trying to cut back, you've probably already reduced the amount of coffee, tea and sodas that you consume. But the sneaky stimulant can pop up in unexpected places. Since the U.S. Food and Drug Administration (FDA) doesn't require manufacturers to list caffeine content on nutrition labels, it's often hard to tell whether a product contains the stimulant, and how much. These 12 sources of caffeine — some hidden, some just plain weird — could be giving you the jitters.

Decaf coffee
The name implies that this cup of java delivers all the taste you love without the caffeine, but don't be fooled. In 2007, Consumer Reports tested 36 cups of decaffeinated coffee from six coffee standbys including Starbucks and Dunkin' Donuts. Compared to the caffeine found in a regular cup (generally around 100 milligrams), the decaf samples had less, but some packed in over 20.

Non-cola sodas
Colas and other sodas like Mountain Dew are well-known caffeinated culprits, but others play less obvious roles in your daily caffeine intake. Some brands of root beer, such as Barq's, contain caffeine. Both the regular and diet flavors have 23 milligrams per 12-ounce can, just 12 milligrams less than a can of Coke. Sunkist's orange soda has a surprising 41 milligrams of caffeine, and A&W Cream Soda has about 25 milligrams.

Caffeine is found naturally in cocoa beans, so any chocolate has a little bit of the stimulant. Candy bars generally have less than 10 milligrams, but the darker the chocolate, the higher the caffeine content. Hershey's Special Dark Chocolate Bar has a whopping 31 milligrams, almost as much as a can of Coke! Some chocolate is fortified with additional caffeine for an energy boost — take the limited edition Snickers Charge, which has 60 milligrams of caffeine, about the same as a cup of tea.

Ice cream
If there's coffee or chocolate in your ice cream, expect the scoop to deliver a small jolt. Many popular brands have coffee flavors that contain between 30 and 45 milligrams of caffeine per half cup, which is about the same as a can of Coke. Chocolate ice cream has much less, however; a half cup of Breyer's All Natural Chocolate ice cream has only 3 milligrams, according to a Consumer Reports analysis.

Weight-loss pills
Caffeine really doesn't do much to shrink your waistline, yet diet pill manufacturers have overloaded their pills with the stimulant. For example, taking 1,223 milligrams in a daily dose of Zantrex-3 is like having 12 cups of coffee, according to a 2005 analysis conducted by ConsumerLab.com.

Pain relievers
A little caffeine can curb headaches, but in large quantities it can actually cause them, some research suggests. Many pain relievers incorporate caffeine to ease the pain, but if you take more than the label suggests, you could be taking more than you need. Two Excedrin Migraine tablets have 130 milligrams of caffeine — the same as a Starbucks Light Frappuccino with espresso — so stick with the two-tablets-per-24-hours label instructions.

Energy water
Riding the coattails of the fortified water trend is a new concoction from various bottling companies: caffeinated water. Some packaging, like that of the former Fruit2O Energy, which boasted as much caffeine as a cup of coffee, displays caffeine content prominently. But others, specifically those flavored with guarana, a Brazilian plant that is a natural source of caffeine, are less obvious; for example, Propel's limited edition Invigorating flavor has 50 milligrams of caffeine, as does VitaminWater's Energy flavor.

Alcoholic energy drinks
A slew of alcoholic energy drinks were reformulated or pulled from shelves after investigators concluded that the products were being marketed to underage drinkers. The Center for Science in the Public Interest sued MillerCoors to stop selling the beverage Sparks, which, according to a lab analysis commissioned by a Miami TV news station, contained a shocking 214 milligrams of caffeine per 16-ounce can — about the same as six cans of Coke. Anheuser-Busch stopped producing fruit-flavored beer Bud Extra, which had 55 milligrams of caffeine, about the same as a cup of tea, as well as the malt beverage Tilt.

Breath fresheners
The makers of Jolt Cola, which had the maximum amount of caffeine allowed in colas before it was reformulated as an energy drink, also sell caffeinated gum and mints. Two pieces of Jolt gum provides the caffeine in a cup of coffee. Three of Penguin's caffeinated mints equal the caffeine content of a cup of coffee, and just one Foosh mint contains the same jolt.

SumSeeds Energized Sunflower Seeds
Marketed as a healthier alternative to energy drinks, these seeds are infused with caffeine, plus natural energy boosters taurine, lysine and ginseng. Sunflower seeds are a vitamin powerhouse, packed with folate, B6 and vitamin E, and they don't contain the added sugar of sodas or energy drinks. But one serving of energized seeds has 140 milligrams of caffeine, about the same as four cans of Coke.

Morning Spark instant oatmeal
Instead of adding fruit or nuts to this healthy food, Sturm Foods has amped up its instant breakfast with caffeine. The packaging boasts that a serving has about as much caffeine as a cup of coffee. Why not just have the coffee with a bowl of regular oatmeal?

Perky Jerky
Looking for your afternoon pick-me-up in a package of beef jerky just seems strange. However, this version actually has less fat and sodium and fewer calories per serving than traditional beef jerky. And it packs a serious punch: One serving has about 75 milligrams of caffeine, about the same as a can of Red Bull.

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