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When the summer sun is blazing, the last thing you want to do is turn on a stove, right? Turns out, eating raw foods does more than just keep you cool—it's a smart strategy for your abs too. A groundbreaking new study from Harvard University revealed that cooking food can actually increase the amount of calories your body absorbs. That's big news: It suggests that adding raw foods to your diet may help you lose weight and expose your abs. And there's no better time to do that than summer, when markets are teeming with ripe produce that doesn't need to be cooked to be delicious.

So why did we ever cook? Fire helped our prehistoric ancestors survive, said Richard Wrangham, a Harvard professor of human evolutionary biology. "Cooked food led to a large increase in our food-energy surplus, helping our brains grow larger and raising our odds of survival and reproduction," he said. Cooking can also help release some nutrients in food. But given the girth problem of modern Americans, it may be time to turn off the heat more often.

"Cooking 'predigests' your food so your body doesn't burn as many calories breaking it down," said Rachel Carmody, a Ph.D. candidate in the department of human evolutionary biology at Harvard and lead author of the study. And because you digest cooked food faster, she said, there's less opportunity for gut bacteria to eat some of it. Plus, Wrangham said, raw food is less digestible, so more passes through unabsorbed. And if you want to slim down, that's just the way you want it. (And if you want a more ways to a leaner belly, Dr. Travis Stork also has a way for you with The Lean Belly Prescription.)

But you don't have to gnaw on celery sticks or raw steak to lose weight. Just pair fresh produce with precooked protein in these meals (all under 550 calories), and you'll harness the belly-flattening power of raw food while staying satisfied all summer long.

1. Why eat raw: You'll chew more

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All those crunchy foods can give your jaw a workout—and that's an advantage when you're looking to drop pounds. In a 2011 study in the American Journal of Clinical Nutrition, men who chewed each bite 40 times consumed 12 percent fewer calories than when they chewed each bite only 15 times. Turns out the extra chewing releases more of a satiety hormone called cholecystokinin; it also lowers levels of ghrelin, a hormone that stokes appetite. Plus, chewing more makes you eat more slowly, which a New Zealand study has linked to lower weight.

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Your move: Start your meals with some raw fruit or a salad packed with crunchy vegetables. In a Penn State study, people who ate a 100-calorie salad 20 minutes before a pasta entree cut their total calorie intake by 11 percent. The same lab found that eating a raw apple 15 minutes before a meal helped diners cut overall calorie intake by 15 percent. (Cooked applesauce, by contrast, had less of an effect.) To make raw vegetables more appetizing, arm yourself with a mandoline (V Blade Mandoline, $40, shopmastrad.com), a multipurpose slicer that can effortlessly julienne crunchy vegetables like beets, carrots, and celery root to boost the chew factor without making you feel like you're on a Bugs Bunny diet. Or just use a vegetable peeler to slice firm produce.

Rotisserie chicken salad with beets and cucumbers

Crunchy vegetables and a quick cilantro salsa transform store-bought roast chicken into a salad that's packed with texture.

2 raw beets, peeled and thinly sliced
1/2 tsp red-pepper flakes
Kosher salt
3/4 tsp red-wine vinegar
5 Tbsp olive oil, plus more for drizzling
1/2 cup half-round cucumber slices
1 Tbsp lemon juice
1/2 cup roughly chopped cilantro (stems included)
3 Tbsp roughly chopped walnuts
1/4 tsp chopped garlic
1/2 rotisserie chicken, removed from the bone and torn into big pieces

1. In a mixing bowl, combine the beets with the red-pepper flakes and 1/2 tsp each of salt and vinegar. Let them sit for 10 minutes, and then mix in 4 Tbsp of olive oil. In another bowl, combine the cucumber with 1 Tbsp each of olive oil and lemon juice, along with a big pinch of salt.

2. In a third bowl, mix the cilantro, walnuts, garlic, 1/4 tsp of vinegar, a pinch of salt, and a drizzle of olive oil. Add the chicken and toss to coat; serve it with the beets and cucumbers. Makes 2 servings

2. Why eat raw: You'll be satisfied with less

In winter, bland imported berries, mealy cold-storage apples, and dusty root vegetables don't make much of an impression on your palate. Come summer, though, the robust intensity of local, in-season fruits and vegetables can help you feel satisfied with less. "Stronger-flavored foods like raw radicchio, green onions, radishes, and arugula induce satiety, tricking your brain into eating less," said Dr. Alan Hirsch, director of the Smell & Taste Treatment and Research Foundation in Chicago. For maximum impact, stick to raw versions of these flavorful fruits and vegetables, since cooking them mellows much of their pungent punch.

Your move: Introduce assertively flavored fruits and vegetables to your meals. The more often you eat them raw, the more tolerable their bite becomes to your palate. So pile peppery arugula or watercress instead of regular lettuce on burgers, stir tart cherries into plain yogurt, add shaved raw radishes to sandwiches, mix sliced red onion into bean salads, and blend grassy kale into smoothies. Don't forget to incorporate ripe, juicy summer fruit into your meals too. Even though it's sweet and not pungent, the intense flavor still satisfies. And for produce with the most flavor, you'll want to hit your local farmers' market. (To harvest some of summer's best produce, check out these 4 Summer Fruit and Vegetable recipes.)

Arugula salad with ricotta, peaches and olives

Think beyond belly-busting manicotti: Ricotta is a great source of protein for salads. For best flavor, use whole-milk or part-skim ricotta. Finish the salad with a fast, pungent olive salsa and honey-sweet fresh peaches.

1 1/2 Tbsp pitted and chopped oil-cured black olives
1 Tbsp thinly sliced scallions
2 cups arugula leaves
1 Tbsp olive oil, plus more for drizzling
1/8 tsp salt
1 lemon
1 ripe peach, cut into thin wedges
1/3 cup ricotta cheese
1/3 cup roughly chopped pistachios

1. In a mixing bowl, combine the olives and scallions. In a larger bowl, toss the arugula with the oil, salt, and a small squeeze of lemon.

2. Divide the arugula between two plates; top it with peach wedges and dollops of ricotta. Finish with pistachios, the olive-scallion mixture, a drizzle of olive oil, and an extra squeeze of lemon. Makes 2 servings

3. Why eat raw: You'll take in more water

We all know we need to stay hydrated in summer. But water-rich fruits and vegetables do more than help replace sweat—they also help fill you up without piling on too many calories. In a study published in the American Journal of Clinical Nutrition, obese people who bumped up their intake of water-rich fruits and vegetables while cutting out some dietary fat shed about 17 pounds in a year, and they felt less hungry than those who only cut back on fat. And since produce contains more water (and more volume) when it's uncooked, you'll maximize those benefits. A cup of raw spinach, for example, has a mere seven calories, versus 41 calories in a cup of cooked spinach.

More water can even help you fire up fat loss, a German study found. That's due in part to the energy needed to warm the water to body temperature. And research also showed that staying well hydrated can rev up metabolism.

Your move: Pack your meals and snacks with especially juicy produce, such as tomatoes, cucumbers, celery, watermelon, and berries. For a hunger-quelling, hydrating snack, whirl water-loaded fruits—cantaloupe, peaches, or apricots, for example—into smoothies, or make cold, raw blender soups like cucumber-yogurt or gazpacho. You can also turn classic gazpacho ingredients into a salad.

Still want to eat like a MAN! Swap the tofu and celery for BURGERS and BEER! Learn more in the Big Book of Nutriton.

Gazpacho chopped salad with mozzarella and prosciutto

Skip the blender, and a classic summer soup, becomes a refreshing main-dish salad fortified by protein-rich fresh mozzarella and thinly sliced prosciutto.

2/3 cup fresh unsalted mozzarella chunks
Kosher salt
2 cups croutons
1 minced garlic clove, pressed to a paste with a little salt on a cutting board
2 Tbsp chopped roasted peppers
1 1/2 Tbsp sherry vinegar
1 cup chopped cucumber
1 tsp red-wine vinegar
1 large tomato, roughly chopped
3 Tbsp olive oil
8 slices prosciutto, roughly torn

1. In a mixing bowl, lightly salt the mozzarella. In another bowl, combine the croutons, garlic paste, peppers, and sherry vinegar. Mix well and let everything sit for 5 minutes.

2. Add the cucumber, wine vinegar, and tomato to a third bowl; season with salt. Add the crouton mixture, olive oil, prosciutto, and mozzarella. Mix well; add more salt and oil if needed. Makes 2 servings

4. Why eat raw: You can cut down on carbs

Shifting the balance of your plate toward vegetables and away from refined carbohydrates can help keep your insulin levels smooth and steady so you're able to maintain a healthy weight. And you don't need to listen to the deafening sounds of your grumbling stomach to make the change. A Penn State study found that substituting a lower-calorie vegetable for some of the grain and meat on your plate can help you cut calorie consumption while keeping you just as full. According to researchers, as long as you see and consume the same volume of food, you're likely to be equally satisfied despite the drop in calories.

Raw vegetables offer even more opportunity to bring down your carb intake. Since vegetables have a tougher, more substantial texture when raw, you can even use them to stand in for chewy carbs like bread, pasta, and tortillas. Just be patient—try the swap a few times to give your tastebuds time to adjust.

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Your move: Use big lettuce leaves instead of tortillas when you make tacos, and serve stir-fry in lettuce cups instead of over rice. Layer stemmed kale leaves or Swiss chard with hummus and turkey for a healthier sandwich, or toss grated raw zucchini with a garlicky pasta sauce and a handful of Parmesan for a fast "pasta" dinner.

Spicy ceviche "tacos" with avocado

No-cook, citrus-spiked ceviche is the ideal summer food. This version has a creamy kick from avocado and hot sauce, and you don't even need a fork to eat it.

1/2 lb fresh skinless red snapper or bass fillets, cut into 1-inch pieces
1/2 cup fresh lime juice
1/4 Tbsp kosher salt, plus more to taste
1/2 cup thinly sliced red onion
2 serrano chilies, finely chopped
1 small roma or plum tomato, finely chopped
1/3 cup chopped cilantro
8 butter lettuce leaves, washed and dried
1 avocado, pitted and cut into thin wedges
Hot sauce (optional)
Olive oil to taste

1. Combine the fish, lime juice, 1/4 Tbsp salt, onion, and chilies in a bowl and refrigerate for at least 3 hours and up to 8.

2. Remove the bowl from the fridge and mix in the tomato and cilantro. Divide the lettuce between two plates; top with avocado, plus salt and hot sauce to taste. Spoon the ceviche and its liquid over the top and drizzle with olive oil. Makes 2 servings

Note: Consuming raw fish may increase your risk of foodborne illness.

5. Why eat raw: You'll boost fiber

Piling your plate with raw fruits and vegetables is a fast way to take in more fiber, an essential nutrient for weight loss. "Fiber slows digestion and minimizes blood-sugar fluctuations so you feel full longer," said Brian Zehetner, chief science officer for Anytime Fitness. In fact, a Brigham Young University study showed that every gram of fiber you add to 1,000 calories of food may help you drop about half a pound of body weight over a 20-month period. So simply using raw produce to raise your fiber intake by 10 grams a day (something most guys need to do anyway) could help trim over 5 pounds from your body over that time.

Your move: Aim for a total of 38 grams of fiber a day, the amount recommended by the Academy of Nutrition and Dietetics. To hit the mark, pack your meals with the most fiber-filled summer fruits and vegetables—raspberries, blackberries, corn, green beans, and dark leafy greens. A pancake breakfast kind of guy? Stir berries into the batter. Or add pureed raw corn (yes, you can eat it raw) to pasta, Mexican dishes like tacos and salsa, soups, or scrambled eggs. You can even make pesto with fiber-rich kale instead of basil and spread it on your sandwich. "Elevate the fiber in frozen pizza and dinners by adding raw broccoli or red bell pepper," Zehetner suggested.

Spicy salami and raw corn salad with Pecorino

Only real summer corn is tender and sweet enough to be served raw. Toss in a few shavings of spicy salami and salty Pecorino, and you'll create an instant Italian feast.

1/4 cup thinly sliced red onion (about 1/4 onion)
1 Tbsp white-wine vinegar
3/4 tsp salt
2 1/2 cups raw corn kernels (about four medium ears)
1/2 Tbsp chopped fresh marjoram or basil
1 Tbsp olive oil
10 thin slices good soppressata salami, torn into rough pieces
Shaved Pecorino Romano cheese, for topping

1. Put the onion slices in a bowl with the vinegar and salt. Let stand for 10 to 12 minutes.

2. Add the corn kernels to the bowl and mix well. Add the marjoram, olive oil, and torn soppressata. Mix lightly to combine. Spoon onto plates and top each with some fresh shaved Pecorino Romano. Makes 2 servings.

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