By David Zinczenko

“I’m going broke,” my friend Brian told me. “Logging on to my bank account is like watching an ice cube in the Sahara.”

I was sorry to hear about his dilemma. What was driving him to financial ruin? Wine? Gambling? What sort of money-sapping addiction had my poor friend in its grasp?

“Trying to eat healthy,” he explained. “For example, every Saturday I go to the farmers’ market and shell out $24 a pound—for kale! It’s costing me a fortune. But if you want to eat right, you gotta shell out for the good stuff, no?”

I shook my head. At Eat This, Not That!, we spend a lot of time unmasking health imposters. And the truth is, the superpowers of kale, like the dangers of the Bermuda Triangle, have been highly exaggerated. Sure, it’s good for you, but the ranking of kale as our greatest green is just one of many word-of-mouth myths that drive our nutritional decision-making, often in the wrong direction. Much of what we believe about food is really just heresay, a game of nutritional telephone handed down from science journals to newspapers to television to your Aunt Phoebe to your mom and then to you, with marketers confusing the message in between.

Learn how to separate fact from fiction and you might finally shed the habits that are silently sabotaging your chances of losing weight. But I must warn you: The truth can hurt.

NUTRITION MYTH #1: Kale is our healthiest green.

A 2014 study at William Patterson University ranked fruits and vegetables by their nutrient density, based on their levels of 17 different nutrients that have been linked to improved cardiovascular health. Not surprisingly, the top 16 were all leafy greens, which pack the most nutrition per calorie. (Coming in at #17 was red bell peppers.) But kale didn’t even make the top 10. In fact, simple spinach and even Romaine lettuce beat the alleged supergreen, as did parsley and chives. Even stuff you normally throw away—the greens atop beets—pack more nutrition. (For the full breakdown, check out these 13 leafy greens that are healthier than kale.)

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NUTRITION MYTH #2: High Fructose Corn Syrup is worse than table sugar.

Sugar is the master of disguise. Maltodextrin, brown rice syrup, dextrose, sucrose—it’s got more alter egos than the Avengers. But it’s most well-known costume is High Fructose Corn Syrup. Whether HFCS is worse than plain ol’ table sugar has long been a contentious issue. Here’s what you need to know: In a 2014 review of five studies comparing the effects of sugar and HFCS, there was no difference found in changes in blood glucose levels, lipid levels, or appetite between table sugar consumption and HFCS consumption. In other words, your body can’t tell one from the other—they’re both just sugar. HFCS’s real sin is that it’s super cheap, and as a result, it’s added to everything from cereal to ketchup to salad dressing. Is it a good idea to minimize the HFCS in your diet? Absolutely. It’s best to cut out all unnecessary sugars. But HFCS’s role as nutritional enemy #1 has been exaggerated. In fact, we found 5 food additives that are worse than high fructose corn syrup.

NUTRITION MYTH #3: Diet sodas help keep you slim.

The obesity-research community is becoming increasingly aware that the artificial sweeteners used in diet soda—aspartame and sucralose, for instance—lead to hard-to-control food urges later in the day. One Purdue study discovered that rats took in more calories if they’d been fed artificial sweeteners prior to mealtime, and a University of Texas study found that people who consume just three diet sodas per week were more than 40 percent more likely to be obese. Try weaning yourself off by switching to carbonated water and flavoring with lemon, cucumber, and fresh herbs.

A study in the American Journal of Public Health found that more obese adults drink diet soda than healthy-weight adults and that, among the overweight and obese adults studied, those who drank diet soda ate more calories than those who consumed sweetened/regular soda. Researchers have also linked regular diet soda consumption with decreased response to artificial sweeteners and a decreased link between sweet tastes and energy value, meaning their bodies may grow to disassociate sweetness with satiety cues, making it easier to overeat and, therefore, gain weight.

Diet and regular drinkers alike, it’s finally time to kick the habit! Here are 5 surprising reasons we should say no to soda.

NUTRITION MYTH #4: Yogurt is good for the bacteria in your belly.

Sure, some yogurts contain beneficial bacteria that can send reinforcements to your gut when you need them. Lactobacillus acidophilus is the bacteria you want to look for, with yogurts that say “live active cultures.” But most yogurts are so high in sugar that they do more to promote unhealthy gut bacteria than anything else. (Unhealthy bacteria feed on sugar in your belly the same way they do around your teeth.)

Avoid the sugar-packed yogurts in the dairy aisle with our guide to the Best & Worst Yogurts (by type).

NUTRITION MYTH #5: Foods labeled “natural” are healthier.

The FDA makes no serious effort to control the use of the word “natural” on nutrition labels. Case in point: 7UP boasts that it’s made with “100% Natural Flavors” when, in fact, the soda is sweetened with a decidedly un-natural dose of high fructose corn syrup. “Corn” is natural, but “high fructose corn syrup” is produced using a centrifuge and a series of chemical reactions. Other “natural” abusers include Natural Cheetos, which are made with maltodextrin and disodium phosphate, and “natural advantage” Post Raisin Bran, which bathes its raisins in both sugar and corn syrup. The worst part is, you’re likely paying a premium price for common junk food.

A recent study just revealed that many foods labeled “natural” actually use GMOs. Here’s a list of “natural” foods that have GMOs that we tracked down.

NUTRITION MYTH #6: Dark Chocolate is good for you.

It would be great if all you had to do to eat healthy was look for chocolate bars that were darker than Kristen Stewart’s mascara. Unfortunately, the secret to unlocking the health benefits of chocolate are a bit more complicated than that. Plenty of studies have shown that polyphenols—nutrients found in darkly colored plant foods like chocolate—can do everything from lowering blood pressure to raising our ability to burn fat. A 2013 study in the journal Diabetic Medicine even found that eating dark chocolate lessened the effects of high blood sugar in diabetic patients. Unfortunately, the more chocolate is processed, the more of the polyphenols are lost. Creating “Dutch” chocolate, in which an alkalizing agent is added to the cocoa to reduce acidity, destroys up to 77 percent of the nutrients in the cocoa. To get the health benefits that have been touted since the time of Montezeuma, look for a dark chocolate that says 70% cacao (or higher) on the label. The rest? It’s just candy.

NUTRITION MYTH #7: Comfort food chases away the blues.

A bowl of tomato soup and a grilled cheese sandwich on a cold winter’s day. A big spoonful of mac & cheese when you’re down on your luck. Comfort food just makes you feel better, doesn’t it?

Actually, it doesn’t. In a 2014 study in the journal Health Psychology, aptly titled “The Myth of Comfort Food,” researchers showed participants depressing films to “induce a negative effect.” Then they gave them either comfort food, foods that weren’t considered comfort foods, or no food at all. Result: The subjects got over their bad moods in equal time, regardless of whether or not they ate. Is feeling bad a good excuse for eating bad? Turns out, it’s not. Cheer up—and start slimming down.

NUTRITION MYTH #8: Peanut butter is a health food.

In its best form, peanut butter actually is a health food. That’s because peanuts are packed with monounsaturated fats, the heart-healthy fat that actually helps you lose weight. Here’s what the ingredients of a healthy jar of peanut butter should read:

Peanuts.

But most peanut butter doesn’t look like that. Here’s what the label of Jif Reduced Fat Creamy Peanut Butter Spread reads like:

Peanuts, corn syrup solids, sugar, pea protein, salt, fully hydrogenated vegetable oils, mono and diglycerides, molasses, magnesium oxide, niacinamide, ferric orthophosphate, zinc oxide, copper sulfate, folic acid, pyridoxine hydrochloride.

Now, I know your kids constantly beg you for seconds of pyridoxine hydrochloride, but is that something they need? Most peanut butters are highly processed and loaded with sugars and trans-fatty oils, and contain less of the healthy monounsaturated fats that you truly need. “Peanut butter spread” is even worse. The word “spread” indicates that it’s at least 10 percent additives. Look for ”natural” peanut butter (Smucker’s and Justin’s both make great versions) and don’t be fooled by any low-fat promises.

We’re not trying to scare you away from all packaged food. Keep our guide to the Purest Packaged Foods with you when you’re buying (and, yes, we included a peanut butter).

NUTRITION MYTH #9: “Multi-grain” and “wheat” breads are better than white bread.

Wait a minute—isn’t “multi-grain” one of the biggest buzzwords in nutrition? And haven’t we been trained to pick the wheat bread over the white at every turn? Yes, but unfortunately those labels are about as credible as your local congressman’s campaign promises. “Wheat bread” is generally white bread with caramel or molasses added to make it look dark and healthy. “Multi-grain” just means that different kinds of junky refined grains may have been used. Always look for the words “100% whole wheat” or “100% whole grain” on the package.

NUTRITION MYTH #10: Nutrition bars are actually nutritious.

In a world where we really called it as it is, nutrition bars would be known by another name: calorie bars. Most of them are so polluted with additives that their ingredients list looks like Charlie Sheen’s blood test results. For example, PowerBar Vanilla Crisp touts itself as “fuel for optimum performance,” but unless you’re talking about a performance by The Chemical Brothers, we’re not sure exactly what they mean. With four different types of sugar, it packs more of the white stuff than an adult woman should eat in an entire day. If you like the idea of a snackable bar that packs in the nutrition, read the ingredients carefully: Brands like KIND, Larabar, and Clif have plenty of smart offerings. But most of what’s out there is just candy.

Do eggs really raise your cholesterol? Are oranges the best source of Vitamin C? Click here 11 more Nutrition Myths debunked.

More From Eat This, Not That:

50 Best Snack Foods in America

5 Daily Habits That Blast Belly Fat

Best & Worst Pizzas in America

7 Small Changes That Will Help You Quit Sugar

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