8 Common Diet Myths Debunked

Stop falling for these popular diet fallacies!

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When it comes to eating healthily — how to do it, when to do it, why to do it — there is no shortage of diet myths and old wives’ tales in widespread circulation. Perhaps you heard that eating celery results in a net loss of calories or that the grapefruit diet is your ticket to keeping fat at bay.

While some myths are easy to spot, other diet myths are more difficult to suss out and can lead to a serious case of dietary confusion. Worse, they can downright stymie your fat-loss efforts and fitness gains if you unsuspectingly fall prey to them. To help you determine which truths to swallow, we’ve investigated — and debunked — some common diet myths that don’t stand up to closer inspection. Psst … whole-wheat bread is not the ultimate enemy, and late-night eating is not a surefire ticket to weight gain.

Diet Myth No. 1: To shed fat, eat low-fat.

The Truth: Ironically, with the widening consumption of low-fat this and low-fat that, America is statistically growing in heart disease and obesity rates. That may be because lackluster ingredients like sugar and refined carbohydrates often replace the fat in “low-fat” or “fat-free” items like peanut butter to make the product taste better. The upshot is that reduced-fat foods like salad dressings and ice cream may have calories nearly on par with the higher-fat versions. What’s more, a Journal of Marketing Research study found that people ate 28 percent more chocolate candies when they were portrayed as “low-fat” than when they were described as “regular.” The researchers surmise that low-fat labels cause people to underestimate calorie consumption, increase what we think is an appropriate serving size, and temper feelings of guilt after eating to excess. Plus, the empty calories from any added sugars and processed carbs can cause you to become hungry again much quicker.

Your Move: Lower-fat or not, products like crackers, cookies and fruit yogurt require you to exercise dietary restraint. Remember that fat is not the enemy and can even be beneficial, as in foods like peanut butter, olive oil, and nuts and seeds. Furthermore, fat can make items more filling, which will function to prevent overeating. So go ahead and pick up that tub of plain 2 percent Greek yogurt instead of the sugar-laden fat-free fruit version.

Diet Myth No. 2: Artificial sweeteners are the answer to your weight-loss goals.

The Truth: While zero-calorie sodas and other artificially sweetened items may seem like a get-out-of-jail card, they may not be all that they’re cracked up to be. Studies suggest that consuming too many artificially sweetened items may result in a paradoxical increase in sugar intake and bodyweight. Case in point: A study by researchers at the University of Texas Health Science Center in San Antonio determined that of the more than 3,600 subjects studied over an eight-year period, there was a 41 percent increase in risk of being overweight for every can or bottle of diet soft drink a person consumed each day. In contrast, those who drank a can of regular sweetened soda every day experienced a 30 percent spike in chances of being too pudgy. The theory is that calorie-free sweeteners like aspartame and sucralose may whet your appetite for sweets, causing you to overindulge in diet-derailing sugar-laden foods when given the chance later on. And faux sweeteners may not teach your taste buds to enjoy a diet that is less sweet.

Your Move: Whether your sweet-tasting drink of choice contains corn syrup or a laboratory-derived artificial sweetener, it’s best to steer clear of if you find it isn’t helping your weight-loss journey. A better bet is to imbibe beverages like green tea, unsweetened coffee and protein-packed low-fat milk. The one exception is during prolonged endurance workouts, when you can benefit from the added fast-digesting carbohydrates of a sports drink.

Diet Myth No. 3: Wheat is evil.

Your Move: Ditching gluten-containing grains like wheat and rye can certainly help those with celiac disease or gluten sensitivity, but if you don’t fall into one of these categories, there is no pressing need to send gluten packing. In fact, there is evidence that keeping grains in your diet can be beneficial. Studies show that whole-grain eaters have an easier time keeping their midriffs slim, so just make sure to shop for whole-wheat breads, pastas and cereals. And whether you’re living wheat-free or not, don’t overlook nutrient-packed gluten-free whole grains like quinoa, millet and teff, which are a great way to load up on the carbohydrates necessary to power through workouts.

Diet Myth No. 4: Shutter the kitchen after 8 p.m.

The Truth: The urging to avoid late-night eating is based on the notion that one’s metabolism becomes listless late in the day — a time when what you eat is thought to be more likely to pack on the fat. But the reality is that there is no magic time to stop eating, and while you may have a slightly higher metabolism earlier in the day to burn off what you eat, the impact on fat loss is likely small. Your overall food choices during a 24-hour period are much more important when dieting because calories can’t tell time. Yes, late-night eating is going to add the same calories to your diet that it would have if you have eaten too much earlier in the day.

Besides, a recent investigation in the journal Medicine and Science in Sports and Exercise trumpets the benefits of a pre-bed protein nosh. Subjects taking part in strength training who consumed about 40 grams of protein a half-hour before bed experienced significantly better muscle protein synthesis than those who ate a placebo.

Your Move: While nobody craves kale when plopped in front of the tube, it’s vital to make wise food choices when snacking late (read: not mindlessly plowing through a bag of chips or tub of chocolate chunk ice cream). To encourage building lean body mass and quelling appetite, focus on high-protein items like Greek yogurt, a protein bar, cottage cheese, beef jerky or even hard-boiled eggs.

Diet Myth No. 5: Practice moderation.

The Truth: Food manufacturers who devote themselves to selling heavily processed foods love to talk about the importance of eating everything in moderation. So as long you eat those muffins and cheesecake in moderation, you won’t suffer any waistline repercussions, they claim.

Yet too much so-called “moderation” can easily add up to a day of junk-food-laden eating that can make the difference between reaching your goals and falling short. Why? Because more often than not, the foods associated with the advice to eat in moderation are nutritional duds. Think about it. When was the last time someone had to counsel you to eat spinach in moderation?

Your Move: When trying to lean down, practice real moderation by allowing yourself no more than one cheat item, of a reasonable portion, per day. Any more than this and your moderation can quickly look like excess.

Diet Myth No. 6: A calorie is a calorie.

The Truth: On paper, it’s simple math. A single gram of carbohydrates or protein contains 4 calories, whereas a gram of fat delivers 9 calories. But calories are not always what they appear to be. For starters, there’s plenty of evidence that eating the same number of calories from processed foods encourages greater fat gain than eating them from whole foods like lean protein, fruits and whole grains. Proof that bundling calories with nutrients plays a roll in weight loss comes from a University of Florida study that reported that subjects who took in more antioxidants had a better buff-to-blubber ratio than those who had lower intakes, even though calorie consumption in both groups was the same.

Further, the thermic effect of food — meaning the energy your body expends to chew, digest, absorb, transport and store the food you eat — is significantly higher for protein than it is for carbohydrates or fat. So even though carbs and protein have the same calories per gram, the human body stores less of them from the latter. This is likely a major reason why high-protein diets have been shown to help torch body fat.

Your Move: Total calories do matter when trying to chisel out a glance-worthy physique, but the quality of those calories is just as important. Focus on obtaining about 90 percent of your daily calories from whole, nutrient-dense foods, and make sure a sizable chunk of them comes from protein options like fish, unsweetened dairy products and eggs to keep your calorie-burning metabolism humming along. Also, we say it all the time, but be sure to have a whey protein shake before and after workouts — and consider adding another one as a snack during the day. A 2011 American Journal of Clinical Nutrition study found that whey has a particularly high thermic effect on the body.

Diet Myth No. 7: Mini-meals are better than three hearty ones.

The Truth: You’ve heard the advice: Nosh on several small meals a day to keep your fat-torching metabolism humming along at a healthy clip. But here’s the thing. There’s no substantial evidence that eating frequency really matters all that much, according to a review of studies by researchers at the University of Newcastle, Australia. Their conclusion? For fat loss, it’s not when or how often you eat that matters as much as what you eat and how much.

Your Move: Whether you eat several small meals or old-school-style three larger meals a day, be sure to pay close attention to how much you’re consuming. You can eat a couple of times a day or 10, as long as you have the same caloric intake and choose the appropriate whole foods that will jump-start fat loss and muscle building.

Diet Myth No. 8: The weekend is for splurging.

The Truth: The two S days represent 30 percent of the week, so easing up on your diet too much on the weekend could easily put the wobble in your step come the workweek. An investigation in the journal Obesity discovered that subjects involved in a fat-loss program lost weight during the week but that they stopped losing pounds over the weekend because they were eating too much. Why? The researchers found that participants consumed more calories on Saturdays than on any other day of the week. By feasting on whatever you want come the weekend, you can largely cancel out five days’ worth of healthy eating. This constitutes a “one step forward, two steps back” approach to dieting.

Your Move: If you’re serious about shedding the fat, don’t give your diet the weekend off. It’s OK to indulge in a slice of deep-dish pizza or chocolate cake on the weekend, but try to maintain your healthy eating from the previous week. If you allow yourself a few small treats throughout the week, you won’t feel an overwhelming desire to binge on nutritional dreck once Friday night rolls around.