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1. Make Your Sandwiches Greek

We've all heard of swapping mayo for mustard, a lower-calorie choice. But what if you don't like the yellow stuff? Go Greek—yogurt, that is. Per tablespoon, nonfat Greek yogurt contains a healthy dose of protein and good-for-the-gut probiotics, plus about 80 fewer calories than mayo, says Keri Gans, a registered dietician and the author of The Small Change Diet says. Plus...that tangy taste.

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2. Claim the Middle Piece of Cake

Let your coworkers have the coveted corner pieces at the next office birthday party. "They're covered with about three times more icing than the middle ones," says Wesley Delbridge, a registered dietitian and spokesperson for the Academy of Nutrition and Dietetics. Ask for a middle piece (and one that doesn't have any of those frosting flowers, either) and you'll still get enough icing to satisfy your sweet tooth. Two tablespoons of store-bought vanilla frosting has 138 calories, and picking from the middle will likely save you that much or more.

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3. Change Your Steak Order

A 6-ounce sirloin contains 300 calories and only 3 grams of saturated fat. That's 100 fewer calories and 6 fewer grams of saturated fat than the same-size rib-eye steak, says Holly Herrington, a registered dietitian at the Center for Lifestyle Medicine at Northwestern University. If sirloin isn't on the menu, ask your waiter what lean and extra-lean cuts are available (or your butcher, if you're doing steakhouse night at home). Those cuts are from the more muscular parts of the animal, so not only do they contain fewer calories, but a greater percentage of those calories come from protein rather than fat.

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4. Get Your Fill of Protein

What helped women eat 97 fewer calories at lunch? Eating high-protein breakfasts, found a study in Nutrition Journal. The secret: Protein increases your levels of feeling-full hormones clear into the afternoon, according to the researchers. Women in the study were eating sausage and eggs, but you can score roughly the same amount of protein from a cup of Greek yogurt or cottage cheese and handful of almonds or a cup of chia seed pudding and an avocado egg bake.

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5. Downsize Your Two-Egg Omelet

A jumbo egg contains 90 calories, while smaller pullet eggs—from young chickens, aka "pullets"—contain roughly half the calories, says Delbridge. Some people say pullet eggs are more flavorful than their oversized counterparts, so you'll need less cheese to doctor them up too. If you can't find them near you (farmers' markets are your best bet), use small eggs (54 calories each) instead.

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6. Use Cinnamon as Your Cold-Brew-Coffee Sweetener

It has precisely zero calories and is packed with more antioxidants and flavor than anything else you could sweeten your drink with, says Gans. Use it instead of your local coffee shop's simple syrup (often added to iced coffee too) or agave nectar (which has 65 calories per tablespoon) and you could easily save 100 calories or more. Double or triple that per day if you're a true java junky.
orange juice

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7. Cut Your Juice with Bubbles

We're not talking about making mimosas. You know that fruit juice is basically a sugar-delivery system, with 110 calories and 23 grams of sugar per cup. But if your morning meal just doesn't feel right without a glass (or two) of OJ, there is something you can do: Make your glass half juice and half sparkling water, says Gans, for a still-flavorful alternative.

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8. Dip Your Salad Fork in Dressing

This comes in handy if you don't want to ditch your favorite dressing for vinegar or a drizzle of oil. Order the dressing on the side and then, instead of delicately pouring it onto your salad or dunking each bite straight into the container, Delbridge recommends dipping your fork's tines into the dressing and then spearing a mouthful of salad. You'll easily end up cutting a couple of tablespoons of dressing from your meal without feeling like you're eating un-dressed greens. If you're a ranch fan, that's 128 calories gone.

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9. Drink Water as an "Appetizer"

You'll wind up eating less without giving it a thought. People who drank 16 ounces (2 cups) of water 30 minutes before breakfast went on to eat an average of 74 fewer calories during just that meal, in a study in the Journal of the American Dietetic Association. Meanwhile, a study in Obesity found that people who drank water before their biggest meals of the day lost about 9 pounds after 12 weeks without changing anything else about their diet.