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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1. Quinoa


You don't have to say quinoa correctly for it to pump you up like Hans and Franz (but in case you want to, it's KEEN-wah). "While the little grain is 60 percent carbs, it's also low-glycemic, so it won't cause dramatic spikes in your blood sugar," says Alexandra Caspero, R.D., owner of the weight-management and sports-nutrition service Delicious Knowledge . The easy-to-digest ancient grain is a protein and fiber powerhouse that helps sustain energy throughout the day. For a simple energy boost, try swapping it for high-glycemic white pasta.

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2. Water-filled fruits



Are you sleepy or thirsty? People often confuse the two, Caspero says. Hydration is key to helping your blood transport oxygen and hormones throughout your body for energy. To rehydrate while carbing up, fill half of your plate at each meal with raw fruits like watermelon, cantaloupe, and berries. They can amount to two extra cups of water a day or more, according to an Iowa State University study. Toss cubed watermelon with finely chopped mint and a pinch of Feta cheese for a healthy snack.

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3. Lentils

Green and red lentils in a wooden spoons

Green and red lentils in a wooden spoons. Close-up.

Fiber doesn't just help women in yogurt commercials with their daily business. It also works to maintain stable blood-sugar (read: energy) levels throughout the day, Caspero says. One cup of cooked lentils packs about two-thirds of your daily recommended dose of fiber. She recommends cooking them up with some taco seasoning for a healthy spin on Tex-Mex.

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4. Oatmeal



Not only does it absorb water as it cooks, oatmeal is also full of soluble fiber to keep you energized hours after digging in. Mix it up with different toppings to prevent boredom and score some extra energy-boosting nutrients. Caspero recommends peanut butter, berries, cacao powder, and bananas.

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