Editor's note: This popular story from the Daily Briefing's archives was republished on June 2, 2023.

Writing for the New York Times, Sophie Egan surveyed some of the top nutrition experts in the country to identify — and debunk — 10 common nutrition myths about fat, plant-based protein, dairy, and more. 

1. Fresh produce is always healthier than canned, frozen, or dried alternatives

While there is a longstanding belief that "fresh is best," research  suggests that frozen, canned, and dried fruits and vegetables can provide just as much nutrition as fresh produce.

"They can also be a money saver and an easy way to make sure there are always fruits and vegetables available at home," said Sara Bleich, the outgoing director of nutrition security and health equity at the U.S. Department of Agriculture and a professor of public health policy at the Harvard T.H. Chan School of Public Health.

However, Bleich recommended reading nutrition labels to check for ingredients like added sugars, saturated fats, and sodium to find products with minimal additives.

2. All fat should be avoided

In the past, health experts, the food industry, and the media suggested that a diet with low fat intake would prevent issues like heart disease or obesity.

However, Vijaya Surampudi, an assistant professor of medicine at the University of California, Los Angeles, Center for Human Nutrition, said that "the vilification of fats" led many individuals and food manufacturers to replace calories from fat with calories from refined carbohydrates, including white flour and added sugar, Egan writes. "Instead of helping the country stay slim, the rates of overweight and obesity went up significantly," Surampudi said.

According to Surampudi, not all fats should be avoided. While certain fats can increase the risk of conditions like heart disease or stroke, healthy fats help lower your risk. "Good fats are also important for supplying energy, producing important hormones, supporting cell function and aiding in the absorption of some nutrients," Egan writes.

3. Calorie intake is the most important factor for long-term weight gain

"[R]esearch does not suggest that eating more [calories] will cause sustained weight gain that results in becoming overweight or obese," Egan writes.

"Rather, it's the types of foods we eat that may be the long-term drivers" of those conditions, said Dariush Mozaffarian, a professor of nutrition and medicine at the Friedman School of Nutrition Science and Policy at Tufts University.

Ultimately, maintaining a healthy weight requires "a shift from counting calories to prioritizing healthy eating overall — quality over quantity," Egan adds.

4. Individuals with Type 2 diabetes should avoid fruit

This myth stems from the idea that whole fruits have the same effect as fruit juices that have a high sugar and low fiber content, which trigger an increase in blood sugar levels.

Linda Shiue, an internist and the director of culinary medicine and lifestyle medicine at Kaiser Permanente San Francisco, said individuals with Type 2 diabetes can benefit from the nutrients in fruit, including fiber, vitamins, minerals, and antioxidants.

5. Plant-based milks are healthier than dairy milk

Many people believe that plant-based milks, including those made from oats, almonds, rice, and hemp, provide more nutrition than cow's milk. "It's just not true," said Kathleen Merrigan, a professor of sustainable food systems at Arizona State University and a former U.S. deputy secretary of agriculture.

While plant-based beverages can have varying levels of nutrition, Merrigan noted that many have a higher amount of added ingredients that can contribute to poor health.

6. White potatoes are unhealthy

According to Daphene Altema-Johnson, a program officer of food communities and public health at the Johns Hopkins Center for a Livable Future, potatoes can benefit your health in many ways. In particular, they contain vitamin C, potassium, fiber, and other nutrients — especially when they are eaten with the skin.

"They are also inexpensive and found year-round in grocery stores, making them more accessible," Egan writes. "Healthier preparation methods include roasting, baking, boiling and air frying."

7. Young children should not consume peanut products

Previously, experts advised new parents to refrain from feeding their children common allergenic foods, including peanuts and eggs, in their first few years of life.

Now, allergy experts recommend introducing peanut products to children early on. Ruchi Gupta, a professor of pediatrics and the director of the Center for Food Allergy & Asthma Research at the Northwestern Feinberg School of Medicine, recommended mixing two teaspoons of smooth peanut butter with water, breast milk, or formula, two to three times each week.

"It is also important to feed your baby a diverse diet in their first year of life to prevent food allergies," Gupta said.

8. Plant-based protein is incomplete

"'Where do you get your protein?' is the No. 1 question vegetarians get asked," said Christopher Gardner, a nutrition scientist and professor of medicine at Stanford University. "The myth is that plants are completely missing some amino acids." However, Gardner noted that all plant-based foods contain all 20 amino acids, including the nine essential amino acids.

9. Soy-based foods increase breast cancer risk

While animal studies found that high doses of plant estrogens in soy called isoflavones stimulate breast tumor cell growth, Frank Hu, a professor and the chair of the department of nutrition at the Harvard T.H. Chan School of Public Health, noted that "this relationship has not been substantiated in human studies."

"Soy foods are also a powerhouse of beneficial nutrients related to reduced heart disease risk, such as high-quality protein, fiber, vitamins and minerals," Hu said.

"The research is clear: Feel confident incorporating soy foods into your diet," Egan writes.

10. Nutrition guidance changes a lot

"In the 1950s, the first dietary recommendations for prevention of obesity, Type 2 diabetes, heart disease and the like advised balancing calories and minimizing foods high in saturated fat, salt and sugar. The current U.S. Dietary Guidelines urge the same," said Marion Nestle, a professor emerita of nutrition, food studies and public health at New York University.

"Yes, science evolves, but the bottom-line dietary guidance remains consistent," Egan writes.

According to Nestle, author Michael Pollan's advice to "Eat food. Not too much. Mostly plants," worked 70 years ago and still works today. In addition, "it leaves plenty of room for eating foods you love," Egan adds. (Egan, New York Times, 1/19)