Get the facts about these 5 health and nutrition myths

When it comes to health and natural remedies it's enticing to grab onto juicy half-truths and hearsay. The most persistent nutrition myths are those that contain at least some truth. Here are 5 common summer health myths to watch out for.

-Brierley Wright, M.S., R.D., Nutrition Editor

Always wear sunblock

1. Always wear sunblock

Thanks to our obsession with sunscreen-as well as a short list of vitamin-D-rich foods and hours spent indoors-three out of four Americans don't get enough vitamin D. While we once thought vitamin-D deficiency was only a problem for people living in northern latitudes, a 2010 Pediatrics study found that 56 percent of teens living in the sunny South were vitamin-D-insufficient, meaning they didn't soak up enough rays to produce the amount of D required for optimal health. The recommended quota (600 IU daily, 800 if you're over 71) is critical for strong bones, but many experts say you may need even more to lower risk of heart disease, type 2 diabetes, multiple sclerosis and many kinds of cancer (the upper limit is 4,000 IU).

Healthy Tip: Bare it all…briefly. Michael F. Holick, Ph.D., M.D., director of the vitamin D, skin and bone laboratory at Boston University School of Medicine, recommends everyone get 10 to 15 minutes of sun on their arms and legs (and abdomen and back when possible) sans sunscreen three times a week during spring, summer and fall (when you can get enough UV rays to produce sufficient vitamin D). He also suggests everyone eat D-rich foods (namely wild-caught salmon, which delivers more D than farmed salmon; UV-exposed mushrooms; and fortified dairy and orange juice) and take a supplement of 1,500 to 2,000 IU of vitamin D3 each day.


2. Eating ice cream packs on the pounds

If you're the kind of person who loves to cap off dinner with something sweet-say, some ice cream-but bans it whenever you're trying to lose weight, you might be making a mistake. According to a study in Proceedings of the National Academy of Sciences, banning sugary foods could lead to overeating. One reason may be that removing access to sweet foods stimulates the release of a molecule in your brain called corticotropin-releasing factor (CRF), produced when you're afraid, anxious or stressed, says Pietro Cottone, Ph.D., lead study author. And increased stress levels may lower your motivation to eat more nutritious foods, making it more likely that you'll binge on junk food. Healthy eating isn't about depriving yourself of everything you love-it's just about eating fewer calories than you're burning, a tactic that can be delicious and can most certainly include dessert. The key is making room for the calories by planning your snacks and meals to accommodate your favorite summer treats.

Healthy Tip: Ask for a cone. Licking ice cream is more satisfying than eating it with a spoon, says Kay McMath, a food technologist for New Zealand's Massey University. "Flavor in ice cream is released when the fat-which carries the flavor-is warmed to at least body temperature," McMath explains. When you lick ice cream it coats the tongue and fully warms the frozen treat. A spoon, on the other hand, insulates the ice cream. And then there's the psychological aspect of savoring the treat more slowly: "You just cannot lick ice cream as fast as you can spoon it." Find out what the best ice creams are nutritionally here.


3. Eating garlic will help ward off mosquitoes

Garlic may keep vampires at bay, but unfortunately it won't keep mosquitoes away. Researchers at the University of Connecticut tested the theory without success, although they did suggest that perhaps participants hadn't eaten enough garlic to see results.

Healthy Tip: Leave the experimenting to the experts. And for now, stick to bug sprays, citronella candles and long-sleeved clothing to fight the critters this season.


4. Eating raw honey will help your allergies

Eating honey to prevent allergies probably won't help. Honeybees gather pollen from the very plants that cause your itchy eyes, so consuming a small daily dose of the local honey-and subsequently these pollens-may stimulate your immune system and reduce allergies, explains Miguel P. Wolbert, an allergist and immunologist at the Allergy & Asthma Care Center in Evansville, Indiana. But the pollens that cause sneezing and congestion-such as ragweed-are windborne, while the pollens bees collect are too heavy to fly in the breeze. Windborne pollens can fall onto flowers, get picked up by bees and end up in honey, says Wolbert, "but it's likely to be a very, very small amount." Not enough to make a difference. And, so far, no clinical evidence shows that honey alleviates allergy symptoms. Find out which foods may actually help fight allergies and asthma here.

Healthy Tip: Even though it's not likely that honey will help your allergies, Wolbert says, "I don't tell my patients not to eat it." Honey has other things going for it: it has equal parts glucose and fructose and research suggests this carb blend may be superior to straight glucose for boosting energy during endurance activities. Honey also contains some antioxidants and vitamins-and the darker the honey, the more disease-fighting compounds it contains.


5. You need 8 glasses of water a day to avoid dehydration

The Institute of Medicine says adult men need about 13 cups (3 liters) per day of fluid; adult women need about 9 cups (2.2 liters) of fluid. (You get about an additional 2 1/2 cups of fluid from foods.) "But one size doesn't fit all," says Leslie Bonci, R.D., C.S.S.D., director of sports nutrition at the Center for Sports Medicine at the University of Pittsburgh Medical Center and dietitian for the Pittsburgh Steelers. Your size and activity level affect your fluid requirements. Simply put, the larger and more active you are, the more you'll need.

Healthy Tip: Assess yourself. "The easiest thing that anybody could do on a daily basis is monitor their urine color," says Douglas Casa, Ph.D., A.T.C., who studies hydration at the University of Connecticut. "Lighter urine color-like lemonade-means you're generally well-hydrated. If it's darker, like apple juice, you are most likely dehydrated."