How much caffeine is really in your coffee?

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CHARLOTTE — That morning cup of coffee feels routine, right? But the caffeine kick might not be.

Consumer Reports tested popular coffees and found that caffeine can vary a lot. In some cases, just one large cup is enough to push you right up against or even past what’s recommended for the entire day.

Research shows coffee can have real health benefits for your heart and brain, but there’s a catch. Too much caffeine can leave you jittery, wide awake at midnight, or nursing a headache.

The Food and Drug Administration recommends adults take in no more than 400 milligrams a day, but how can you tell how much caffeine is in your cup of coffee?

Coffee companies aren’t required to tell you how much caffeine is in their brews, whether you’re buying a bag at the store or picking up a takeout cup.

Which is why Consumer Reports recently tested caffeine levels in ground and instant coffees from grocery stores, such as Folgers and Café Bustello, and in cups brewed at popular coffee shops, including Dunkin’ and Starbucks.

The results? Caffeine levels vary dramatically. Of all the ground coffees tested, Café Bustelo Espresso had the most caffeine. Instant coffees were generally lower in caffeine than traditional ground varieties.

At coffee shops, Peet’s Major Dickason’s Blend Dark Roast and Starbucks Pike Place Medium Roast had the highest caffeine levels. A large cup of either one would put you over the FDA’s 400-milligram daily limit. As with anything, moderation is key. You don’t need a lot of coffee to get its health benefits.

And remember, coffee might not be the only source of caffeine in your day. Tea, soda, energy drinks, and even chocolate can all add up. So, before you reach for that refill, it might be worth asking yourself, do you really need it?

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