7 Shocking Weight Loss Mistakes Even Food Experts Fall For

Updated: Mar. 30, 2022

Food experts reveal the eating and weight loss mistakes they see other health professionals make and how to avoid them.

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Weight loss mistakes made by food experts

The adage “Do as I say, not as I do” applies to nutrition and diet advice as much as anything else. Even nutritionists can’t estimate calories correctly, explains New York University nutrition professor Marion Nestle, PhD, in her book Why Calories Count. In one experiment, nutritionist Lisa Young found that when dietitians were asked to estimate the number of calories in several fast-food meals during a meeting of the American Dietetic Association, they underestimated the amount by about 30 percent. What’s more, even the most well-meaning health experts may give outdated advice. Read on to learn the biggest weight loss mistakes even health professionals make—and how to outsmart them.

spinach with eggs and bran muffin

Mistake: Cutting too many calories

One of the most common weight loss mistakes is thinking that it’s: “Cut calories, lose weight.” This is the most basic weight loss advice, but eating too little can actually slow your metabolism, causing the pounds to creep back on. “Even if you’re restricting calories healthfully, it’s hard to meet all your nutritional needs when you go too low,” says registered dietitian Samantha Heller, author of Get Smart: Samantha Heller’s Nutrition Prescription for Boosting Brain Power and Optimizing Total Body Health. It’s a trap she says she’s seen experts fall into, thinking that an extreme weight loss program may help “get me kick-started.”

Smart weight solution

Don’t fall for big gimmicks. Depending on your size, activity level, and other factors, dipping below 1,200 calories a day isn’t a good idea for long-term weight loss. (Follow the 7 rules of counting calories to make sure you’re losing weight the healthy way.)

fruits and vegetables with organic sign

Mistake: Falling for “health halos”

So-called “healthy foods” such as green juices, whole-grain pretzels, or organic-labeled anything may coax you into eating more than you usually would. “Last night, someone brought these coconut vegan donuts to a party I was hosting,” shares registered dietitian Brooke Alpert, RD, founder of B Nutritious, a private practice in New York City. “And this morning I couldn’t help but eat one after I dropped my daughter off at school, even though I would otherwise never eat dessert at 10 in the morning. I’m proof that even professionals fall for health halos!”

Smart weight solution

Read nutrition labels, and be mindful of your choices. Ask yourself, “Am I really hungry right now? Do I need to be eating this?” and try sipping a glass of water first to see if those pangs go away.

loaves of bread

Mistake: Not embracing carbs

“A common piece of advice I see others give out is to ‘scoop out your bagel’ or cut out carbs to lose weight,” says Heller. “But what’s the point of indulging in a bagel if you’re going to scoop it out?” She adds that it’s easy to overdo it with carbs, but eliminating them isn’t healthy either. “Skimping on whole grains means skimping on energy, as well as fiber, B vitamins, vitamin E, protein, and antioxidants,” Heller says. “They also help balance blood sugar highs and lows.”

Smart weight solution

Don’t ditch carbs—in fact, any weight-loss plan that eliminates entire categories of nutrients is a big, fat red flag. But re-educate yourself about serving sizes (read labels, use measuring cups) to make sure you eat a reasonable amount. (Here are some examples of carbs that really are good for you.)

woman looking into a refrigerator

Mistake: Believing eating at night causes weight gain

Some evidence, especially from animal studies, suggests that late-night munching packs on pounds, but encouraging people to cut off eating at an arbitrary time isn’t a good idea. “It’s OK if you eat dinner at 8 or 9 p.m.—you have to eat, after all,” says Heller, who’d rather people eat dinner late than skip it, wake up famished, and start the next day off on a binge. A bigger problem is eating all evening: nibbling when you get home from work, having dinner, then snacking while you watch TV or relax. Before you know it, you’ve munched for four hours straight.

Smart weight solution

Portion out specific meals on plates and eat them sitting down at the table, not in front of the TV, or standing up in the kitchen. (Don’t have enough time? Here are healthy meal ideas you can make in 20 minutes.)

bowl of food in skilled with fork

Mistake: Getting portions wrong

No matter how healthy your meal choices, eating too much will thwart your weight loss. Too many of us, health experts included, have no clue what a real portion looks like. A recommended 3-ounce serving of meat, poultry, or fish is much tinier than you think—the size of a deck of cards. A cup of cereal is just the size of your fist. A half-cup of ice cream is about the size of half a baseball. “Even we don’t have X-ray eyes,” says Heller, “we’re all susceptible to environmental influences that encourage us to overeat.”

Smart weight solution

Spend a day measuring out portions to gauge just how wrong or right you really are, then course correct. Just being aware of your environmental influences can give you more control over your eating habits. (Don’t miss these other portion control tricks that can help you lose weight.)

pouring olive oil

Mistake: Thinking fat is the enemy

“At this point, anything low-fat makes my skin crawl,” says Alpert. “Fat is such a necessity in our diets, but people are still petrified of fat.” Alpert, who is confident that eating more healthy fat and less sugar is how we should be battling the obesity epidemic, is surprised to still see others recommending strict low-fat diets to clients.

Smart weight solution

Eat some filling, healthy fat at each meal: nuts in your breakfast cereal, an olive oil-based dressing on your salad for lunch, grilled salmon for dinner. When processed foods cut out fat, they typically have to add in sugar, salt, and other unhealthy ingredients to compensate for taste; these can still make your body cling to weight.

woman doing pushups

Mistake: Being too busy to be healthy

What over-extended professional hasn’t felt like there’s no time to squeeze in a workout or eat a home-cooked meal? This can’t-do-it-all mentality affects health and nutrition experts as much as the rest of us, says Alpert. “When I start neglecting myself—skipping my morning run or spinning class—I feel it a couple of days later. I’m more lethargic, I lose my patience more easily. I have to tell myself ‘OK, mama needs to eat a salad’ to get back on track and feel better.”

Smart weight solution

Life’s busy traps ensnare the best of us. When they do, remember this mantra Alpert uses: “The healthier you feel, the better and more efficient you’ll be at your job, and the happier you’ll be with your family and friends.”

Start by trying out these easy tricks that can make anyone healthier, and you’ll be turning them into regular healthy habits in no time.