When it comes to eating healthy , one of the main obstacles is an avalanche of unreliable information. Conflicting headlines, fad diets, and misinformation make it difficult to determine what is actually good for you and what is harmful. Adding to the uncertainty are manufacturers who place misleading labels on their products, and social media influencers who endorse certain eating habits and diets without having any nutrition experience. Here are 10 of the most common nutritional myths and the truth about each one.
Fat got a bad rap in the ’90s, when low-fat diets were the rage of the time, and many in the country are still confused about the role of fat in a healthy diet.
Animal fats, which are more saturated, are related to cardiovascular diseases. But healthier monounsaturated and polyunsaturated fats , found in fish, avocados, olives and olive oil, eggs, nuts and seeds, can reduce the risk of cardiovascular disease and death.
Although all types of fat are high in calories, fats “stay in your stomach longer,” says Fung, “which helps you stay full longer and not want to reach for a snack so quickly.”
2. Myth: The best way to reduce sodium is to put away the salt shaker
The vast majority of people in the United States consume too much salt, and if you have high blood pressure, reducing your sodium intake could be a matter of life or death.
But because most of our sodium in the United States comes from prepared foods, avoiding the salt shaker at dinner isn’t going to make much of a difference, Fung says.
Breads, salad dressings, pasta sauces, canned beans, cheese, and many processed foods and packaged snacks are full of sodium, he says. Even boneless, skinless chicken breasts can be injected with a brine that increases sodium levels. Restaurant food is also full of salt, and some contain the amount of sodium you should eat in a day in a single meal, according to a study in the Canadian Journal of Public Health .
Fung recommends cooking at home as often as possible, comparing labels and choosing low-sodium versions of packaged and prepared foods.
3. Myth: Foods with “whole grains” or “multiple grains” on the label are always healthy
You know that foods made with whole grains are healthier than those with refined flour, but labels can be misleading.
“Made with whole grains ” and “multigrain” may sound healthy, says Fung, but they often mean that a product contains only a small amount of whole grains, while the rest is refined.
Fung recommends looking for products labeled “whole grain” or “whole wheat,” meaning they are made with at least 51% whole ingredients. Better yet, choose one that says “100% whole grain.” You can also check the ingredients list to make sure a whole grain is included first.
Sugar-free and low-carb diets like keto and paleo are popular, which might lead you to believe that anything with carbs or sugar is bad for your health. However, there is a big difference between the natural sugars in fruits and vegetables and the added sugars and refined starches in processed foods, says Dr. Dariush Mozaffarian, cardiologist, public health scientist and director of the Food Is Medicine Institute at Tufts University. Cutting back on added sugars and refined carbohydrates is probably the best thing you can do to control your weight, says Mozaffarian.
But don’t stop eating fruits and vegetables. Not only do they contain healthy vitamins, minerals, fiber, and other micronutrients, but studies show that eating more of them is linked to a longer life and reduces the risk of death from all causes.
5. Myth: Fresh products are healthier than frozen ones
There’s nothing better than picking fresh raspberries or peas at the farmer’s market. But if it’s the dead of winter, without local produce, rest assured that you won’t miss out on any nutrients if you buy frozen foods at the supermarket, says Valter Longo, a gerontologist, cellular biologist and director of the Longevity Institute at the University of Southern California.
Frozen produce tends to be picked at the peak of ripeness, and studies show that frozen foods have as many vitamins and antioxidants as fresh foods, and in some cases even more. Plus, the longer you store fresh produce, the more of its nutritional value is lost, according to research.
“Food can oxidize and become contaminated over time,” says Longo. “If you buy berries and freeze some and leave others out, the ones you froze might be fresher than the ones you left out.”
You may have seen posts on social media claiming that canola oil, sunflower oil, and other seed oils are toxic, but science doesn’t support this, Mozaffarian says. “There is very clear evidence that they are beneficial,” he says.
7. Myth: Gluten-free foods are healthier
Gluten is a protein found in grains, including wheat, barley, and rye. People with celiac disease should eliminate gluten from their diet to prevent damage to their intestines and other parts of the body. And for those with gluten sensitivity, eliminating gluten can help with symptoms of bloating, diarrhea, or abdominal pain, according to Harvard Medical School.
“These are all terms that have some relevance, but you can’t define a healthy diet by lacking something,” he says. “You can eat natural, organic, gluten-free foods that are terrible for you anyway.”
The idea behind this myth is that eating small, frequent meals could boost your metabolism to burn more calories.
A third problem, Longo says, is that “in the real world, if you tell people to eat five or six small meals, they’re just going to eat more or eat more of the wrong things.”
Longo recommends eating breakfast and then eating another large meal and a third smaller meal or snack each day.
9. Myth: It is a good idea to detox or cleanse
Different detox diets and juice cleanses are popular on social media, but studies show few benefits and a risk of harm.
A 2014 review study, for example, found no evidence that detox diets remove toxins from the body or help with long-term weight loss. Even if you lose weight during a cleanse, a 2017 study in the journal Nutrition and Obesity found that most people actually gain weight when they return to eating normally.
Perhaps more concerning is that cleansing can cause serious side effects, including gastrointestinal problems, protein and vitamin deficiencies, dehydration, and electrolyte imbalance, according to the National Center for Complementary and Integrative Health.
10. Myth: The only thing that matters is “calories in, calories out.”
It’s true that if you burn more energy than you consume, you will probably lose weight, at least in the short term. But for your overall health, “calories in and calories out” is an oversimplified notion that doesn’t explain the influence different types of foods have on your overall health, Mozaffarian says.
Two foods with the same amount of calories can have different effects on your hormones, gut microbiome, and metabolism, he says. A handful of nuts, for example, will take longer to digest compared to a bag of Cheetos. And the latest research shows that starchy and sugary foods tend to contribute to visceral fat, which has been linked to heart disease and other illnesses, while fatty foods tend to contribute to subcutaneous fat, which is less harmful.
For overall health and weight loss, Mozaffarian recommends choosing nutrient-dense whole foods instead of processed foods with added sugar and refined carbohydrates.