When it comes to nutrition, advice can feel like a minefield. New research may contradict studies that came out only a few years ago, and then get replaced by fresh insight soon after publication. The fast pace of change in the nutrition world can make it challenging to separate myth from reality.
Here, nutritionists share their insights to help you navigate through a few of the more tenacious misconceptions.
Like so many nutrition beliefs, this one likely sprang up because it worked for some people and so it got repeated — but the truth is much more complicated, says registered dietitian Joy Dubost.
“Unfortunately, there is no magic equation or straightforward formula for losing weight,” she says. “I think this myth has staying power because it allows people to focus on cutting calories with the hope of accomplishing a weight-loss goal in a short amount of time. However, it’s a false hope that promotes unrealistic expectations.”
The relationship between changes in caloric intake and weight loss simply isn’t that linear, she adds. As you increase or decrease your calories per day, your body and its metabolic system adapts to compensate for the change. That doesn’t mean changing your calorie intake has no effect on weight, of course, but Dubost emphasizes that if you’re doing the “500 calorie cut” plan and not seeing results, you’re not alone.
As a phrase, this is a compelling and powerful one, says registered dietitian Maya Feller. The word “clean” conjures up positive associations that border on being virtuous, she says. The problem is it has no standard definition, so it’s being used in multiple ways that make it confusing to follow.
“Seriously, this phrase needs to be taken out of circulation,” says Feller. “It means everything and nothing, all at the same time.”
When her patients talk about wanting to “eat clean,” Feller asks what they mean and says she gets a wide variety of answers. Some people mean they simply want to add more vegetables into their rotation, while others are talking about doing a juice cleanse or never eating refined grains again.
If your intention with “clean eating” is to consume more whole foods and avoid overly processed options, though, then Feller says that’s a sound strategy with good scientific evidence to support its efficacy. Maybe you can just call it something else, like “eating real food.”
“Let’s find a new way of encouraging folks to lean in to embracing whole and minimally processed food on a regular and consistent basis in place of ultra-processed foods,” says Feller.
Yes, this one is still around, despite numerous studies, expert commentaries and news articles debunking it. The message that eating fat leads to being fat is deeply ingrained in people who grew up hearing that about that cause-and-effect relationship all the time.
“So many people believe that the amount of fat, or any fat at all, in a food is the main culprit for weight gain,” says Brigitte Zeitlin, RD, of BZ Nutrition. “In reality, fat does not make you fat.”
We all need a certain amount of fat in our diet to help us absorb vitamins and minerals, boost energy, fight inflammation and aid muscle function. “Fat will actually help improve your workouts and get you to your fitness goals,” she says. “It can also help to fight constipation.”
But, she adds, it is important to keep in mind that not all fats are alike. There are healthy fats that improve good cholesterol and bad ones like trans fats that do the opposite. By switching to a fat-free product, though, Zeitlin says you’re likely to take in much more salt and sugar, since those are added to make up for the flavor loss that comes from ditching fat.
“That added sugar is actually what is contributing to weight gain,” Zeitlin notes. “Healthy fat is what helps satiate so that you don’t overeat or over-snack, avoiding those extra calories and weight gain.”
Here’s another pervasive myth, Zeitlin says. Many people believe that if they eat less throughout the day, they’ll weigh less eventually — this is a variation on the simplistic calorie-cutting formula that doesn’t work either.
“This plan always backfires and never leads to healthy, maintainable weight loss,” says Zeitlin. That’s because when we don’t have enough food during the day, the body’s metabolism slows down to conserve energy, so you’re actually burning fewer calories than you normally would.
“Also, you are guaranteeing that you’ll overeat at your next meal, because you’ll have starved your system,” she adds. Instead of skipping meals, she advises people to eat a combination of vegetables, fruits, whole grains and lean protein about every four hours to keep metabolism on track and boost weight-loss or weight-maintenance goals.