Put down the coffee and back away from the energy drinks. Food—not caffeine—is your body's natural fuel, and noshing on the right sources can give you the kick in the butt you need to power through the day. So what food gives you the biggest buzz? Turns out it's our frenemy, the carbohydrate. Recent research from the Penn State College of Medicine found that increased carb intake results in all-day alertness.

That's not an excuse to order a meatball sub with a side of lasagna for lunch thinking you'll soar through your work day. If you carb, carb smart. Refined, processed carbs will make your energy crash after a mere 30 minutes, and overloading on the sweet stuff hoping for a sugar high might land you with a sleep disorder.

Here, four carb-filled foods that bring all-day energy.

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