You Lack Supplement Savvy

Health.com: 27 Mistakes Healthy People Make

More is not better when it comes to vitamins and supplements, and too much of a good thing can actually be harmful.

In 2011, an analysis of data on nearly 40,000 women found that those who took dietary supplements—especially iron—were actually at slightly higher risk of dying, although the investigators weren't sure why. "There's no really long-term studies that show unequivocal benefits of taking vitamin and mineral supplements," says Dr. Rogg. "If you're going to take supplements, take them in moderation, and stick to the recommended daily doses."

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Smart People, No...

You pick healthy food, work out (when you can), and watch your waistline. That means you're healthy right?

Not so fast—many people who are in tip-top shape (for now) have habits or beliefs that can put them at risk for illness or injury down the road.

Read on to learn about these common mistakes, and how you can avoid them.

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You Always Buy O...

Buying organic is wise for certain foods, such as beef or strawberries, but it doesn't make much difference for others, like avocados or eggs.

And don't assume that all organic foods are healthier than non-organic options, or that organic equals healthy. Organic choices are usually pricier, for one thing. And organic high-calorie, high-fat granola bars and sugary cereals are just as bad for you as the non-organic version.

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You Don't Social...

While you may feel virtuous on your long solo runs, don't forget to check in with your pals once in a while. Studies suggest that social networks are good for your health too.

Try to schedule regular meet-ups with friends, whether it's a book club or poker—it doesn't matter. (No need to make it exercise-based, although that's nice too.)

Just connecting with other people, and maintaining those social networks as you age, is good for your health.

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You Skimp on Sle...

Think it's a good idea to get up at 5 a.m. and hit the gym? Not if you should be sleeping instead, says Gary Rogg, MD, a primary care physician and assistant professor at Montefiore Medical Center in the Bronx, N.Y. Studies have consistently shown that people need at least seven hours of sleep a night for optimal health, and short sleep has been associated with a host of health problems, including high blood pressure, depression, diabetes, and a reduced immune response to vaccines.

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You Lack Supplem...

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You Get Unnecess...

As with vitamins and minerals, more does not always mean better when it comes to medical tests. Especially tests marketed directly to consumers, like the cardiac calcium-scoring test. While this test—a CT scan that identifies calcium deposits in the heart arteries—is useful for a select group of at-risk people, it isn't for everyone, says Dr. Rogg. It also exposes you to a whopping amount of radiation—the equivalent of 25 to 50 chest X-rays.

Several US medical specialty groups have launched an initiative, Choosing Wisely, to draw attention to overuse of 45 medical tests, and encourage physicians to avoid tests and procedures of questionable benefit.

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You Beg for Anti...

Many people ask their doctor for a prescription for antibiotics or antivirals for symptoms that probably would resolve on their own, or just because they fear getting sick.

And some doctors may oblige. But these drugs also carry risks, from contributing to the huge problem of drug resistance to killing off the good bacteria in your body. Let your doctor decide if your symptoms warrant medication, and skip the high-pressure tactics.

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You're a Germaph...

We all know people who never leave the house without their hand sanitizer—you may even be that person. And yes, you should wash your hands with soap and water to kill germs that can make you sick.

But evidence also suggests that some germ exposure could steer the immune system away from allergies, and that an overly sterile environment might be bad. (It's called the hygiene hypothesis.) Good bacteria are also key for staying healthy, particularly for the skin, digestive tract, and vagina. So "fear of germs" does not equal "good health."

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You Over- or Und...

Once upon a time, it was hard to get the medical establishment to recognize that acupuncture, herbal remedies, or biofeedback could sometimes heal people as well as big-name drugs.

Now we know that if you dismiss acupuncture as “quackery,” you may be missing out on your best therapy yet. At the same time, if you over-rely on alternative medicine—opting for a herbal remedies instead of chemotherapy, for instance—you may also be missing out on the best cure yet.

Try to keep an open mind and consult the experts to make informed choices.

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You Delay Medica...

You’re healthy, so that crushing chest pain has to be heartburn, right? Or weakness and confusion can't be a stroke, right?

Wrong. All too often, people stall or explain away serious symptoms, when in fact, rapid treatment can help prevent permanent heart or brain damage.

Doctors say "time is tissue," meaning the faster you get treatment for a stroke or heart attack the less heart or brain tissue you lose. So don't delay if you have stroke or heart attack symptoms.

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You Use Exercise...

Regular exercise is crucial for health and maintaining a healthy weight, but it won't help you lose weight unless you cut down your calorie intake.

"Patients exercise themselves until they're blue in the face, they're frustrated, they're sort of at a loss as to why they haven't had success," says Shantanu Nundy, MD, a primary care physician at the University of Chicago. But the truth is that exercise—maybe because it whets the appetite, maybe because we decide it's OK to reward ourselves with a treat after that workout, maybe both—often makes people eat more, which means you'll make up for the calories you just burned, and then some.

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You Ignore Sodiu...

You watch your calories. You avoid meals dripping with saturated fat. But sodium? All too often that's the ingredient that gets ignored when weighing healthy options.

High sodium intake has been firmly tied to an increased risk of high blood pressure, and the average American eats well over the recommended amount. Most of the excess sodium we consume comes from packaged and prepared foods, from spaghetti sauce to frozen dinners. Always check nutrition labels for sodium content; the Institute of Medicine recommends people limit their intake to below 2,300 milligrams per day, and 1,500 mg for people 51 and older, African Americans, and anyone with high blood pressure or diabetes.

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You Guzzle Calor...

Artificially sweetened beverages may free of calories, but it doesn't mean they're all that great for your health.

A couple of studies released at the 2011 American Diabetes Association's annual meeting suggest just the opposite. One found that older people who drank lots of diet soda saw their waistlines expand five times more over a decade than their peers who didn't drink diet soda at all, while another showed that mice fed the artificial sweetener aspartame had higher blood-sugar levels.

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You Drink Too Mu...

Dehydration is bad. So more water is good, right? That's true, to a point.

But particularly if you're running your first marathon or some other physically taxing, long event it's important to avoid drinking too much water, which could lead to water intoxication (also known as hyponatremia).

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You Lie to Your ...

Many of us don't tell our doc everything—say, we smoke cigarettes or drink more than we should. Or we may take that prescription with no intention of ever filling it. Harvard Medical School researchers found that more than one in five first-time prescriptions never got filled (this was especially true for chronic conditions such as high cholesterol, high blood pressure, and diabetes).

But you're better off being straight with your doctor, who can help you find ways to kick the habit or find a treatment you'll actually take (or be able to afford).

If you don't feel you can be fully honest with your doctor, says Dr. Nundy, you should look for a new one.

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You Think You Kn...

With the Internet at our fingertips, we all feel smarter than we did in the past. And well-moderated online forums can be a great resource for helping people with certain health concerns get support and stay informed.

But they are no substitute for a doctor’s advice.

“I think a common mistake is to sort of put more faith in those resources than health care professionals,” says Dr. Nundy, the author of "Stay Healthy at Every Age: What Your Doctor Wants You to Know."

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You Think Health...

Food or cosmetics products that boast of being all natural may sound appealing and wholesome, but in fact, the US Food and Drug Administration has a pretty loose definition of just what that word means.

The FDA is OK with any product claiming to be natural, as long as it doesn't contain added color, artificial flavor, or synthetic substances.

Low fat is another tricky claim. The FDA does have clear guidelines on when a product can claim to be low- or reduced-fat, but these products may still be high in sugar, sodium, or calories—or all of the above.

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You Exercise Too...

Pushing yourself is usually a good thing when it comes to physical activity. But your body needs rest, too, especially after an extra-hard workout. Signs that you are working out too hard can be mental and physical, and include fatigue, difficulty sleeping, decreased immunity, muscle soreness, and injury. To keep your workout fresh—and avoid overuse injuries—it's a good idea to vary your routine, and give yourself a day off now and then. "Sometimes, just sitting back and relaxing is better for your body than going to the gym for that hour," says Dr. Rogg.

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You Still Don't ...

By now, pretty much everyone knows they should be eating at least five servings of fruit and vegetables per day. Eating plenty of produce helps reduce your risk of heart disease and several types of cancer, and can help you manage your weight too. But a state-by-state survey by the Centers for Disease Control and Prevention found that in 2009, just one-third of adults reported eating at least two servings of fruit a day, and only about one-quarter ate three or more servings of veggies daily.

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You Obsess Over ...

Health shouldn't be seen as something to strive for, but as a way of life, Dr. Rogg says. "When you focus on keeping healthy as an endpoint, as opposed to a healthy lifestyle, you may tend to sort of miss the whole picture."

Too often, Dr. Rogg says, people who want to be healthy focus on avoiding "bad" foods and obsess about numbers, like their body mass index. "The focus that people have to make is on being happy and on things that will make them happy, and enjoy themselves."

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You Skip Vaccine...

Grown ups need shots, too, but many of us don't get them—raising our risk of contracting a host of unpleasant, deadly—and preventable—illnesses, from the flu to cervical cancer to shingles. Just one in five at-risk adults under 65 received the pneumococcal vaccine, for example.

Recommendations for adult vaccine coverage vary based on age, health, where you travel and what you're exposed to, but the Centers for Disease Control and Prevention recommends an annual flu shot for everyone, and a diphtheria-tetanus-pertussis booster every 10 years for adults. Check out the full list of recommended vaccines for adults.

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You Don't Have H...

Good health habits are contagious, and bad health habits are, too. Several recent studies have shown that obesity, cigarette smoking—even happiness—spread through social networks.

Try to forge friendships with people whose health habits you'd like to emulate and encouraging your friends to join you in healthy pursuits.

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You Avoid Doctor...

You know you should eat better, exercise, lose weight, quit smoking—what more can a doctor do to help? A lot, says Dr. Nundy. Studies have shown people have a better chance of trying to quit smoking, and succeeding, when a doctor advises them to do so. Doctors can also prescribe medications that can greatly increase quitting success. And while there's unfortunately no safe pill to help people lose weight, a doctor's advice can give you a better chance of succeeding in trimming down as well, Dr. Nundy says.

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You Don't Read N...

A nutrition label—which contains information on a food's calories, sugar, fat, and sodium content—will tell you the real story about whether those "natural" or "low-fat" foods are actually good for you.

"Just because something is turkey or chicken doesn't necessarily mean it's low-fat or low-salt," says Dr. Rogg. Be sure to pay attention to the portion size listed on the label, too.

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You Think High-T...

While invasive treatments, like stents to prop open clogged heart arteries, may sound pretty cool, says Dr. Nundy, "you would have been much better off had you not had a blockage in the first place."

So don't think the gee-whiz medical techniques of the future are going to cure you down the road, but do take a day off to get a good old-fashioned checkup. "There's no substitute for prevention," he says. "We have lots of pounds of cures, but they're not perfect."

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You Don't Have a...

"A lot of people don't really have a relationship with a primary care physician or a health care facility," says Dr. Nundy. "I think that's a huge mistake."

Finding a physician who you like and trust, and building a partnership with him or her over time, is one of the best things you can do for your health, according to Dr. Nundy.

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Skipping Checkup...

Similarly, many people may not bother to go for well visits, but just go to see a doctor when they're sick or in pain.

This can mean missing important screening tests, which can catch problems early when they are much more treatable—and also missing a chance to get to know your doctor.

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You're Clueless ...

Moving, switching insurance plans and changing doctors can leave your medical records scattered to the winds. You don't need to have a filing cabinet stuffed with the results of every medical test you've ever taken, but keeping track of a few key pieces of health information can go a long way toward making sure you get the health care you need, Dr. Nundy advises. At minimum, you should keep track of which vaccines you've received and when, as well as the dates and results of your most recent screening tests.

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