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8 Diet Myths That are Making You Fat

Believing that these rumors are rules is actually widening your waistline.

Nothing is more frustrating than stepping on the scale and seeing that the needle hasn't budged—not even a little bit.

This holds especially true when it feels like you've been religiously following every diet tip in the book. But when it comes to diet and rapid weight loss, there's a lot of misinformation floating around, so you may not be making progress simply because you've been following bad advice. (Cue the facepalm.)

There's good news, though: You've already proven to yourself that you have great willpower and determination; all you have to do is shift that energy to weight loss tips that actually have backing instead of following diet myths that are just keeping you fat and frustrated. Here, we reveal the most pervasive diet rumors that you need to stop following—stat!

You Can Eat Whatever You Want if You Work Out

Man holding beer reaching for slice of pizza

Reality Check: Unfortunately, a half hour trot on the treadmill isn't going to help you lose weight if you reward yourself by downing a few slices of cake and an order of French fries. We know the treadmill told you that you burned off 500 calories, but those estimated machine readouts are not at all accurate—sorry! And even if you did burn 500 calories over the course of an hour, that can all be undone in a matter of minutes: Consume just two slices of Domino's Deluxe Hand Tossed Large Pizza, and you've consumed 640 calories and 26 grams of fat. The bottom line: It's near impossible to out-exercise a bad diet unless you plan to spend half your day in the gym. You must workout and eat smart to see results.

You'll Burn More Fat if You Don't Eat Before a Workout

Woman lifting weight

Reality Check: Without the proper fuel you won't be able to work out for as long or as hard as you need to if you want to see a difference in your body. What's worse, fasted workouts can cause low blood sugar and lightheadedness, which can be dangerous when you're breaking a sweat. Plus, when you're running on fumes, you're going to be ravenous after your workout. That means you'll be more apt to make poor diet decisions—like downing an entire pizza—after you get home. On the contrary, the proper fuel before your sweat sesh can actually increase your gains: "A whey protein shake before a workout has been shown to increase muscle synthesis," Jim White, RD, ACSM, and owner of Jim White Fitness & Nutrition Studios tells us.

Going Paleo Guarantees Weight Loss

Paleo meal with steak on a bed of greens

Reality Check: It's no shocker that Paleo is one of the most-Googled diets in recent years. Bacon and steak for weight loss? Yes, please! But the Paleo diet may be too good to be true. Although protein-rich diets help pounds fly off initially, eating a low-carb, high-protein diet can actually cause weight gain in the long-term, according to a study published in Clinical Nutrition. In fact, the Spanish researchers found that those who follow high-protein diets have a 90 percent greater risk of gaining more than 10 percent of their body weight over time than those who don't go heavy on the meat. To reap the weight-loss benefits of the Paleo diet–without paying for it later–nix the processed junk and oils as the diet suggests, but keep the protein in check. Men should get no more than 56 grams a day and women should aim for 46 grams. Take in more than the recommended amount and the excess will likely be stored as fat.

All Calories Are Created Equally

Woman choosing apple over sugar-filled pastry

Reality Check: Eating 300 calories of chicken is not the same as eating 300 calories of cake. The body uses and stores calories differently depending on the nutrients each food is comprised of. For example, getting your protein from plants has actually been found to increase feelings of fullness more than when you consume the same amount of protein from meat. University of Copenhagen researchers found that when participants ate a legume-based meal, they consumed 12 percent fewer calories in their next meal than if they had eaten meat—which could promote weight loss long term. The study authors believe the increased satiety is due to the fact that plant-based proteins contain more belly-filling fiber than meat. It's just another example of how the macronutrient quality of your food can actually trump the idea that "a calorie is a calorie."

You Can't Eat at Night If You Want to Lose Weight

Woman looking in refrigerator late at night

Reality Check: Eating too many calories throughout the day, not nighttime munching, causes weight gain. In fact, "eating the right type of bedtime snack actually boosts metabolism and aids weight loss—not the opposite!" explains Cassie Bjork, RD, LD of Healthy Simple Life. "When you don't eat before bed, blood sugar levels dip so you don't sleep as well. In turn, you crave more sugar- and carb-laden food the next day. If this happens often enough, it can cause weight gain. On the flip side, eating the right snack can help keep blood sugars stable so the fat-burning hormone glucagon can do its job." So what should you be eating? "I suggest pairing a natural carb with a healthy fat." Apple slices and almond butter, berries with heavy cream, and carrots with guacamole all fit the bill.

You Can Eat As Much as You Want, As Long as It's Healthy

Avocado sliced in half
Charles Deluvio/Unsplash

Reality Check: Avocados, oatmeal, nuts and their creamy, delicious butters are indeed healthy, but low in calories they are not. Sure, you're better off eating 200 calories of oatmeal then 200 calories of sugar-spiked cookies made with the grain, but that doesn't give you free rein to eat as much of the stuff as you want. The bottom line: Nutritious or not, portion size counts with every food. If you find that you have trouble sticking to reasonable portion sizes for some of the more caloric healthy foods in your diet, look for portion-controlled packages. Emerald makes 100-calorie almond and walnut packs, Wholly Guacamole sells 100-cal guac, numerous brands sell small oatmeal packages and Justin's has a line of individually-portioned nut butters. Buying mini sizes in lieu of bigger tubs of food helps keep calories in check and teach you what a proper serving looks like.

Protein Shakes and Bars Help You Lose Weight

Protein powder smoothie

Reality Check: Although packaged protein products can be a part of an all-around healthy diet, they aren't any better than a sit-down meal comprised of similar nutrients. However, depending on which bars and shakes you pick up, you could actually be putting your health at risk. Many popular products are filled with bloat-causing additives like carrageenan and whey in addition to caramel coloring, which has been shown to cause cancer in humans. A number of the pumped-up foods also use artificial sweeteners in lieu of sugar, which can increase cravings for sweet treats and cause weight gain over time. Our advice: If you want to include bars and shakes in your diet, opt for one of our Best Protein Bars for Weight Loss and whip up your own protein shakes at home using fresh fruits, veggies, milk or water and a low-sugar protein powder.

Drinking 8 Glasses of Water Daily Guarantees Weight Loss

Lemon water
Daiga Ellaby/Unsplash

Reality Check: While chugging water and running to and from the bathroom go hand in hand, chugging water and weight loss do not. "Drinking water does not guarantee weight loss—especially if you're still eating an unhealthy, high-calorie diet," says Lisa Moskovitz, RD, founder of Manhattan-based private practice, The NY Nutrition Group. But that doesn't mean you should stop running to the water cooler. "Staying hydrated throughout the day is a great habit to maintain for good health, it's just not the only change you'll need to make for permanent weight loss," Moskovitz adds. Not sure what else you should do to get trim? Check out our 200 Best Weight Loss Tips.

This article was originally published February 2, 2016.

Dana Leigh Smith
Dana has written for Women's Health, Prevention, Reader's Digest, and countless other publications. Read more about Dana Leigh
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