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Is microwaving food safe? 7 nutrition myths debunked

Do you need to drink one glass of water for every caffeinated beverage you drink? Are “white foods” like onions less nutritious than broccoli? Is dark chocolate really rich in antioxidants? Read on to learn the truth about seven common nutrition myths.

1Myth: Multigrain foods are rich in whole grains

When a food is labeled "multigrain," it means that more than one type of grain was used in the product -- though none of them are necessarily whole grains. This is also true for products such as “seven-grain” bread.

Whole grain means all the parts of the grain kernel -- the bran, germ and endosperm -- are used, allowing for a more nutritious product compared to foods made with refined grains. Whole-grain foods contain nutrients, fiber, and other healthy plant compounds found naturally in grain.

According to an article in the Journal of Nutrition, there is consistent epidemiological evidence indicating that whole grain foods substantially lower a person's risk for developing chronic diseases, such as heart disease, diabetes, and cancer and also play a role in body weight management and digestive health.

To make sure a product is whole grain, look at package labels. The first ingredient listed should contain the word “whole,” such as “whole wheat” or “whole oats.” The USDA recommends healthy *s consume about 6 ounces of total grains per day, and that at least half of those grains (3 ounces) are whole grains.

2Myth: White vegetables lack nutritional value

While you may have been told to steer clear of “white foods” for good health, this advice does not hold up when it comes to white vegetables. Cauliflower, onions, mushrooms, turnips and even potatoes are packed with just as many nutrients as their colorful veggie counterparts. Eating white vegetables can increase intake of fiber, potassium, magnesium, and other vitamins and minerals – in addition to improving overall vegetable consumption, according to a paper published in Advances in Nutrition. The next time you add color to your salad, don’t forget the white.

3Myth: Dark chocolate has more healthful flavanols than milk chocolate

Dark chocolate is often perceived as healthier than milk chocolate because it contains higher concentrations of cocoa. However, dark chocolate does not necessarily have more cocoa flavanols than milk chocolate.

Naturally found in fresh cocoa beans, cocoa flavanols are a unique group of plant nutrients (phytonutrients) that research indicates may help improve circulation, cardiovascular health and blood flow to the brain. According to The National Confectioners Association’s Chocolate Council, the cocoa percentage marked on a chocolate’s label isn’t a reliable indicator of flavanol amounts.

“Cocoa flavanols are easily destroyed by typical processing techniques including the amount of time, temperature and moisture when making cocoa or chocolate. This process starts from the time the cocoa beans are harvested and continues throughout processing,” said Hagen Schroeter, Director of Cocoa Flavanol Research at Mars, Inc.

If you are looking to add more cocoa flavanols to your diet, Schroeter recommends additional sources, such as cocoa extract supplements.

4Myth: Cut calories to lose weight

While cutting calories will likely help you drop a few pounds in the short term, Alyse Levine, a registered dietitian nutritionist and founder of the Eating Reset weight loss program, says if calorie restriction is your main focus, you’ll likely gain more weight in the long term.

“Everyone thinks weight loss is about what they are eating, but losing weight for the long run comes down to why and how you eat,” Levine said.

Rather than focusing on consuming a set number of calories a day, Levine advises her clients take a more holistic approach to weight loss.

“There are three very simple-sounding things I tell people to do to lose weight for the long run: Eat when you are physically hungry, choose whatever foods will satisfy you and stop when you are more than comfortably full," Levine said.

The problem with strict dieting is that it often forces you to ignore physical hunger cues, which can eventually lead to over-indulging. Levine’s philosophy gets you in touch with your physical hunger, creating a healthier dynamic for long-term weight loss.

5Myth: Dietary supplements are a waste of money

Recent recommendations by the U.S. Preventative Services Task Force indicate a lack of evidence that a daily multivitamin will ward off major diseases like cancer and heart disease. However, that doesn’t mean dietary supplements don’t play an important role in your overall wellness, particularly for certain groups of people.

“Some populations like women who are or may become pregnant, people with nutrient deficiencies or malabsorption problems, strict vegetarians or vegans, and older *s may need supplements to meet their increased needs,” said Caroline Kaufman, a registered dietician nutritionist based in Los Angeles.

If you choose to take a multivitamin, Kaufman recommends talking to your health care provider to determine the right type for you as needs vary depending on diet, health history, age and medical conditions. In addition, it’s important to look for quality brands that have been tested and verified by a third-party organization, such as the United States Pharmacopeia (USP).

6Myth: Microwaving food destroys nutrients

This is an old nutrition myth – recently reiterated comically by Jennifer Lawrence’s character in the movie American Hustle – but microwaving food does not destroy nutrients. In fact, according to Kaufman, in some cases microwaving food offers health benefits.

“A fast and convenient way to steam vegetables, microwaving can help people retain more water-soluble nutrients often lost when drowning vegetables in water and cooking them too long. Microwaving also helps preserve heat-sensitive nutrients like vitamin C due to a faster cook time,” Kaufman said.

In addition, partially cooking meat in the microwave means less cooking time over an open flame.

“Microwaving meat before pan-frying or grilling can substantially reduce the formation of potentially cancer-causing chemicals, caused heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs), which cause cancer in animals, and may be linked to colorectal, pancreatic and prostate cancer in humans,” Kaufman advised.

7Myth: Coffee is dehydrating

A January 2021 study published in the journal PLOS ONE found that, contrary to popular belief, your morning cup of coffee will not dehydrate you. Researchers *yzed the hydration status of 50 male coffee-drinkers when they drank four mugs of coffee each day compared to when they drank four cups of water each day and found no difference between the two beverages.

While this is good news for coffee drinkers, Kaufman warns healthy *s should consume no more than 400 mg of caffeine a day -- that’s about 4 cups of brewed coffee, one "venti" Starbucks coffee or 10 cups of green tea. Consuming over 600 mg of caffeine each day is considered “too much” by the FDA because overdoses can be harmful and possibly lethal.

“While caffeinated beverages may help you meet your fluid requirements, in excess, caffeine can have negative effects on health like anxiety, agitation, headaches, insomnia, increased heart rate, dental caries, and more,” Kaufman said.

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