14 Commonly-Held Ideas About Food—And Exactly How True They Are
Some of these have a kernel of truth, and others are completely made up. We take a look, and bring the science.
Just because you read it on the internet doesn’t mean it’s true. We set out to find which of these 14 current food, health, and nutrition statements (and a few steadfast ones) contain more than a kernel of truth.
Cooking in Aluminum Foil Is Dangerous
Verdict: Not Exactly
Science hasn’t shown a confirmed cause-and-effect relationship between cooking with aluminum foil and any disease. But in recent years several studies have shown that heating certain foods (mostly acidic ones) in contact with foil or disposable pans leaches aluminum into food in amounts above the World Health Organization’s acceptable limits. And a 2016 meta-analysis in Neuroscience Letters found that chronic exposure to aluminum (via drinking water or on the job) is associated with a higher risk for Alzheimer’s.
"There is a connection there, but we don’t see enough evidence to connect it to using foil," says Kristin Kirkpatrick, MS, RDN, manager of wellness nutrition services at the Cleveland Clinic Wellness Institute. To err on the side of safety, avoid cooking acidic or heavily salted foods with foil; otherwise you’re good to go.
Activated Charcoal Can Cure a Hangover, Improve Teeth, and More
Doctors use activated charcoal in emergency rooms to absorb poison in your body, so it makes sense that it also would work for everyday toxins, right? Before you grab a scoop of charcoal-blackened ice cream and call it a cleanse, read on: There’s no credible research that shows it works for anything outside the ER. So enjoy the Instagrammably inky food, but don’t expect it to do anything.
Some Foods (Like Celery) Have Negative Calories
It’s been said that it takes more calories to chew and digest celery than you’ll get from eating it. "No matter how hard something is to chew, you will never spend more energy chewing it than what it provides," says Joe Schwarcz, PhD, professor of chemistry and director of the McGill University Office for Science and Society. "If that were the case, you’d lose weight by just chewing gum."
Non-GMO Foods Are Healthier
Someday soon, the opposite will likely be true: Scientists are experimenting with genetic modification to add nutrients to food. If GMO foods feel unsafe to you, know that in the U.S., three different government agencies oversee genetically modified food. "The business of certifying foods as non-GMO is total marketing gimmickry," says Schwarcz. "Certifying agencies are making money off of that." So while there may be other reasons to avoid GMO foods, such as environmental concerns, in terms of nutrition and health, they’re no different.
Sea Salt Is Better for You Than Table Salt
Repeat after us: Salt is salt is salt. "With sea salt, you might get a few more minerals, but it’s still salt," says Diane McKay, PhD, of Tufts’ Friedman School of Nutrition Science and Policy. "And the amount of minerals that you’re getting for the amount of sodium won’t make any difference in your nutrient needs." But there is a difference in the grain size. Coarse-grained salt will generally have less sodium than an equivalent volume of fine-grained. Picture a bucket full of big rocks versus a bucket full of sand—if you ground up the rocks into sand, you’d have much less than a full bucket.
Always Choose Low-Fat Dairy
For years health experts have told us to opt for 1% or skim milk and eat less cheese. Fuller-fat dairy products contain saturated fat, which is linked to increased heart disease risk. But a 2017 analysis of research that included nearly 1 million people found no evidence that dairy— including full-fat milk and cheese—increased the risk of cardiovascular disease or death. Some research even suggests full-fat dairy has health benefits of its own. One group that should always have full-fat dairy: kids under the age of 2 (fat is key for brain development). "If you’re not at risk for heart disease and you prefer whole milk, or a good chunk of full-fat cheese, that’s fine," says McKay. Just be mindful of where else your saturated fat is coming from (red meat, coconut oil, etc.) so as not to go overboard.
Natural Sweeteners Are Healthier Than Refined Sugar
"Sugar is sugar. Honey is sugar. Maple syrup is sugar. Agave is sugar," says McKay. "The body responds to it the same way." Unrefined sugars like honey, molasses, and maple syrup offer some nutrients you won’t find in a spoonful of the white stuff, but not enough to make up for the fact that you’re still eating added sugar. As a 2017 review of studies discussing natural and artificial sugars says, limiting any sweetener may be the best health advice.
Microwave-Safe Plastic Isn’t Really Microwave-Safe
When you cook any type of food in any vessel by any method, some material will migrate from one to the other. What matters is how much migrates and at what level it might be harmful. "You can’t say zero because it’s never zero," says Schwarcz. "If you put your hand on the desk and we swab the desk, we’ll find stuff that came from your hand." When it comes to microwave-safe plastic, the amounts are small enough to be considered safe. Even fewer particles migrate from glass and ceramics, however, so if you’re concerned, use those instead.
Canola Oil Is Toxic
You were probably sent the chain email about the dangers of canola oil—those rumors have been swirling since before the email started making the rounds in 2001. But they’re based on an incomplete understanding of the oil’s origins. "Canola" is a contraction of "Canada" and "ola," or oil. This heart-healthy product was born up north and derived from rapeseed, which contains erucic acid, a fatty acid linked to cardiovascular risks (hence the rumor).
But years of crossbreeding (the traditional way of combining preferred qualities from different breeds of plants, practiced for centuries) have eliminated almost all the erucic acid in the canola plant. What you’ll find at the supermarket is well within safe levels. And the high smoke point, and low levels of saturated fats still make it one of the best to cook with.
Intermittent Fasting Is Good for Health and Weight Loss
Verdict: Mostly Fact
One friend eats with abandon five days a week and takes in very few calories the other two days. Another friend doesn’t eat after 6 p.m. A third forgoes food every other day. And all three say they’ve lost weight and feel great. Science suggests there’s something to it: A 2017 review of 16 studies found that "almost any intermittent fasting regimen can result in some weight loss," though the data on fasting’s impact on general health is still too sparse to draw conclusions.
Soy Has an Estrogenic Effect That’s Bad for Both You
Soy does contain something called phytoestrogen, which mimics the hormone we have in our bodies. But so far, the majority of research into soy’s phytoestrogen finds that it has beneficial properties—four recent reviews of previous studies found that it may protect against high blood pressure, diabetes, cancer, and bone loss, for example. "Soy certainly is not a dangerous substance," says Joe Schwarcz, PhD, Professor of Chemistry and Director of the McGill Office for Science and Society. "But I think it should be thought about as a food, not as a drug. Don’t go taking extra soy—because it’s going to be beneficial for you."
Vegetarians Don’t Get Complete Proteins
Protein is made up of a variety of amino acids, most of which our bodies produce on their own. The nine we can’t make are known as the "essential" amino acids, which often appear in animal products. A "complete" protein contains all nine, and scientists used to think we need to eat them all together in order to be effective. But more recent discoveries have upended that belief. In a 2016 Position Paper, the Academy of Nutrition and Dietetics said, "The terms complete and incomplete are misleading in relation to plant protein. Protein from a variety of plant foods, eaten during the course of a day, supplies enough of all indispensable (essential) amino acids when caloric requirements are met."
Pink Pork Is Unsafe to Eat
Verdict: Mostly Myth
The days of grey, tough pork chops are over. To avoid the parasitic infection trichinosis, the USDA used to recommend cooking pork to an internal temperature of 160°F, which yielded an unappealing, overcooked piece of meat. But in 2011 the guidelines changed: For whole pieces of pork (like roasts, loins, or chops), they now say to cook to an internal temperature of 145°F, and allow it to rest for three minutes before serving.
Meat continues to cook after it comes off the heat, so that’ll bring the pork up to a safe 160°F by the time you eat it—while leaving it rosy and juicy inside. Ground pork, on the other hand, still needs to be cooked until it reaches 160°F, at which point you won’t see pink. The difference? When you grind meat, any parasites or bacteria on the surface are distributed throughout. To kill them, you must cook ground meat fully.
Maca Powder Is Good for Your Energy Level, Libido, and Hormones
Verdict: Mostly Myth
Indigenous peoples in Peru have eaten and used maca root medicinally for 3,000 years, but it’s only become a thing here recently—maybe you’ve seen it referred to as "Peruvian Viagra."
A 2017 review of studies found that "the hype surrounding the claims of maca is not completely misleading," particularly when it comes to energy- and libido-boosting, but there’s not enough evidence to draw conclusions. Which means nobody knows what dose is appropriate for specific uses, or how long to take it. And because supplements are unregulated, you have no way of being sure how much you’re getting.