Been following these rules to stay healthy? You can stop now.

It's your guilty secret: You skip breakfast, though it's the most important meal of the day. Or so you've always heard.

Turns out you can not only skip breakfast, but the guilt, too. Recent research in the British Medical Journal shows that people who miss breakfast are not heavier or less energetic than fans of the meal.

Calories have the same nutritive value no matter when you consume them, says Dr. Seena Shekari, Medical Director of the Valley Medical Group’s primary and walk-in care center in Waldwick. "Your body doesn't have a clock," he says. "That was started by the cereal companies. 'Eat Kelloggs cereal and get your metabolism going.' It was fake."

Whether they're spread by for-profit companies or your elderly aunt, health myths have amazing staying power. Here are some other rules you don't need to follow.

Feed a cold, starve a fever

The phrase would be just as wrong if it were flipped, says Shekari. "There's no science behind this one," he says. "You have to eat no matter what. In fact, you use up energy when you have a fever, so it's a better time to eat, but most people don't feel like it."

You need to drink eight glasses of water a day

This one can be traced to a 1945 report by the U.S. Food and Nutrition Board, which recommended that people consume 2.5 liters — eight glasses — of water daily. "After many studies, surveys and articles, there is no scientific evidence to suggest that (people need) to drink this much," says Julene Stassou, a registered dietician in Bergen County and the author of "The Mediterranean Diet Weight Loss Solution." "We get water from foods like fruits and veggies, and liquids that aren't caffeinated (and dehydrating). Our bodies tell us when we're thirsty." 

The flu shot can give you the flu

"I must talk about this four times a day," says Shekari with a sigh. "There is no flu virus in the flu vaccine. It's a blueprint in the body so your immune system can recognize (the virus) quickly and knock it out before you get sick." Not getting the flu shot, on the other hand, makes you vulnerable to getting sick and spreading illness. 

Taking high levels of vitamins prevents diseases

"My patients ask me about this all the time," says Dr. Shoshana Feiner, an internist with the Summit Medical Group in Fair Lawn. "But we don't see a lot of diseases like low levels of Vitamin D causing rickets, or lack of Vitamin C causing scurvy, in this country anymore."

While large amounts of Vitamin E and antioxidants used to be promoted as good for fighting heart disease, she says, the same claims have been made more recently about Vitamin D. But a recent study by the National Institute of Health debunked this.

"The bottom line is, everything in moderation," she says.

The tryptophan in turkey makes you sleepy

We eat turkey on Thanksgiving, and then we need to nap, so turkey causes sleepiness, right? Not exactly. "Tryptophan is a component of the brain chemical serotonin, which gets converted into the well-known sleep-inducing hormone melatonin," explains Stassou.

But the Thanksgiving meal also includes a lot of carbohydrates, such as mashed potatoes, breads and casseroles, that make tryptophan more available to the brain; with alcohol on top of that, you've got a recipe for nap time.

"Basically, any big meal containing tryptophan and lots of carbohydrates can trigger sleepiness, with or without turkey," she says.  

Carbs are bad

It's not wise to demonize any food category in particular, including that popular villain, carbs, says Dr. Peggy Policastro, a registered dietrician nutritionist and director of the Institute for Food, Nutrition and Health Student Ambassador Program at Rutgers University in New Brunswick. "Whole grains are good for you," she says. "What's unhealthy is processed, refined carbohydrates, which reduce your fiber intake. Healthy foods like carrots don't have an ingredient label, whereas carrot chips do. If you're looking at a litany of ingredients on a label, it's probably not healthy." 

Spending time outside without a coat/with wet hair makes you sick

"There is no science to this," says Feiner. "Colds tend to be worse in the winter because many viruses do better in cold weather, and that's when they spread." Old movies that feature heroines being rescued after hours in the rain and later succumbing in their beds are more romantic than accurate, she says.

"Unless you develop hypothermia, you're not at risk," she says. "Your teen won't catch a cold from walking to school with wet hair."

You'll feel better if you avoid gluten

Feiner says that a lot of her patients want to be tested for celiac disease, a genetic condition that makes it difficult to process gluten, though their blood tests and biopsies almost always come out normal. 

"A true celiac patient will show weight loss, failure to thrive when younger, and severe anemia and osteoporosis when older," she says. "But when they say they feel better cutting gluten from their diets, I say that's fine. There's just no scientific basis for 'having a hard time to tolerating gluten.' " 

Snacking before bedtime leads to weight gain

Again, a calorie is a calorie. The reason late-night eating gets a bad rap is because digesting the food can interfere with sound sleeping, says Policastro.

"During the night, your body's working overtime, you don't sleep as well, your defenses may be down the next day and you may eat more," she says. 

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