There are some common assumptions about dieting and weight loss that we all seem to make: eat your fruits and veggies, drink more water, never forget breakfast, etc. However, a new paper published in the New England Journal of Medicine calls 19 of these prevalent assumptions into question, suggesting we either need to ditch the claims or seek more evidence to support them.
What works in the lab and what experts see in the field can be different, though—which is why we asked New York City-based nutritionist Jaclyn London, M.S., R.D.N., to give us her take on the claims. Are they myths or facts? Here, she fleshes out the truth behind six major assumptions from the study.
Claim #1: Assessing stage of change, or “readiness to diet,” is important in helping patients who pursue weight loss treatment to lose weight.
This is the fancy way of saying that a person will only lose weight if he wants to lose it. While the researchers offer evidence refuting this as a major issue, London says it does play into the mind of registered dietitians when they issue diet plans, despite researchers branding this one as a myth. “There is often an assumption among clients that simply showing up for a consultation will magically make them lose weight,” she says. “I wish it were that simple!” Since dieting isn’t a miracle pill, it’s totally based on a person’s willingness to stick to the plan and exercise—and if a person doesn’t have the time or energy to follow a new regimen, logically, it may fail. Still, since it is hard to study something this subjective, don’t discount this as a total myth. If you want to lose weight, you have to commit to a lifestyle change. “It is a major part of the behavior-change process,” London says. Verdict: Mostly Fact
Claim #2: Regularly eating vs. skipping breakfast is protective against obesity.
If you’re eating a Big Breakfast from McDonald’s instead of a healthy bowl of oatmeal every morning, you’ll probably see the scale creep up—which is why researchers call this presumption into question, and suggest more research. It matters what you eat just as much as when you eat—but, you should eat. “We do already have substantial research to support the claim that breakfast intake is linked with lower BMI,” says London. “Many people think that skipping breakfast is an easy way to cut calories, but the habit typically leads to an increased energy intake throughout the day, making people susceptible to overdoing it at other meals.” So here’s the takeaway: eat healthy, but still eat. Greek yogurt and fruit, almond butter on an English muffin, or whole-grain cereal—there are tons of quick, healthy options. Verdict: Mostly Fact
Claim #3: Eating close to bedtime contributes to weight gain.
Don’t eat after 8 p.m.! At least that’s what common weight-loss wisdom proclaims, but London says it is mostly myth—although studies support both sides of the clam. People tend to believe this old adage, for a couple reasons. “First, much current research links people with fewer hours of sleep per night to a higher risk of overweight obesity, and eating too close to bedtime can frequently be associated with disrupted sleep,” she says. “Second, eating close to bedtime could lead to waking up ‘too full’ to eat breakfast, leading to meal skipping and then binging later on—another inhibitor of weight loss.” Overall intake of calories is more important than timing, though, says London, as the researchers suggest. As long as you’re not skipping meals, focus on hitting your goals, no matter the time. Verdict: Mostly Myth
Claim #4: Eating more fruits and vegetables will lead to weight loss or less weight gain, regardless of whether one intentionally makes any other changes to one’s behavior or environment.
Sadly, simply amping up fruit and veggie intake will not necessarily cause your waist to shrink—but eating more can help. Here’s why: “Fruits and veggies aren’t magic weight loss pills, but they do have the power to impact our intake overall due to their high water-volume and high-fiber content,” says London. “increasing intake of fruits and vegetables can displace other calories from less nutrient-dense sources, like processed foods, and is typically the ‘first line of defense’ when it comes to weight loss.” Which is why dieticians push for it. Eating too much of anything can lead to weight gain, but filling up on fruits and veggies should make you less hungry for the cake and cookies. Verdict: Mostly Fact
Claim #5: Snacking contributes to weight gain and obesity.
“This is another one that is both true and untrue,” says London, insisting that you have to snack right. “Skipping meals can lead to binging at your next meal, so very often, it’s beneficial to recommend choosing healthy, fiber and protein-rich, 150- to 200-calorie snacks to decrease total energy intake for the day.” However, snacking can backfire if you’re downing processed foods or not keeping tabs on exactly what you’re consuming—or how much. “It’s really the mindless snacking and grazing—a handful here, a handful there. That’s where we see problems with clients who can’t seem to lose weight,” London says. “Those extra calories all add up.” Verdict: Mostly Fact
Claim #6: Drinking more water will reduce energy intake and will lead to weight loss or less weight gain, regardless of other changes.
Water is often hyped as a major component in feeling full and flushing bloat, which will help you lose weight. Here’s why this one isn’t entirely true, though, as the researchers suggest: “Yes, it’s true that a lot of people are not as in touch with their ‘thirst’ mechanism or satiety cues as we’d like—it’s not easy and it is definitely the case that we often see people who mistake hunger for thirst,” says London. “That said, I think it’s difficult to say that this is totally true for everyone, not to mention the fact that fluid and hydration needs are different for everyone, based on age, sex, weight, height and physical-activity level.” Drink up and hydrate consistently with (on average) eight glasses a day, but don’t expect water to be a weight-loss miracle drink. Verdict: Mostly Myth
What do you think? Does this research cast doubt on any of your dieting strategies? Tell us in the comments!