Health: WebMD

Secrets Of The Super-Healthy

December 5, 2008 / 4:30 PM EST / WebMD

Are you secretly envious of your co-workers and friends who, like superheroes, never seem to get sick? You know, the ones glowing with good health while everyone around them is sneezing, sniffling, and coughing like villains.

Don't hate the healthy people. Instead, steal the secrets of people who manage to stay above the sickroom fray and take steps to boost your body's immunity.

Training for the Body

Jennifer Cassetta, a martial arts instructor in New York City, claims she never gets sick, and neither do her father and grandmother, who also teach martial arts. "I believe it is the holistic approach to exercise that calms the mind and relieves stress," she says. "And the cardio, strengthening, and conditioning help boost the immune system."

Cassetta says her health has changed dramatically after she picked up martial arts eight years ago. Before then, she was a smoking, take-out-every-night, espresso-drinking girl in her 20s.

"As I started to train, I started to change my habits drastically," she says. "I cleaned up my diet, trained more, and quit smoking. Now in my 30s, I have more energy, I look better, and am stronger than I ever have been."

One bout of vigorous exercise can increase circulation, says Christiane Northrup, MD, author of Women's Bodies, Women's Wisdom. "Whenever circulation is increased, you get far more white blood cells," she says, "so they check for foreign germs and are far more apt to be able to gobble them up."

Pay Attention to Your Mouth

Chicago public relations consultant Joanna Broussard says gargling regularly with an antiseptic mouthwash has helped improve her dental health and may have helped fend off other illnesses.

Twelve years ago, Broussard's dental hygienist convinced her to gargle consistently after brushing her teeth. "So I made the effort and got into the habit every morning," she says, "Since then I have not had colds. When people all around me have colds or the flu, I seem to be immune."

Another reason to bone up on your brushing and gargling is that poor oral hygiene and gum disease have been linked to more serious illnesses, including diabetes.

An Apple a Day Really Works

Your mom may have been right when she said, "An apple a day keeps the doctor away." A natural antioxidant called quercetin, found in red apples as well as broccoli and green tea, may give an immunity boost to individuals under stress.

In a study conducted by David Nieman, PhD, professor at Appalachian State University, results showed that only 5 percent of cyclists who took 1,000 milligrams of quercetin every day for five weeks reported upper respiratory illness during a two-week period following extreme exercise, whereas 45 percent of the cyclists who took a placebo reported illness following extreme exercise. However, there were no significant differences in measures of immune system function in the two groups.

Additionally, researchers found that athletes taking the quercetin supplement maintained better mental alertness and reaction time over the placebo group. So go ahead, stock up on those red apples and you may be thanking Mom later.

Don't Worry, Conquer Stress

Stop worrying about getting sick. The fear and expectation of having something adverse happen actually lowers immunity, says Northrup. "When people are worried about it all the time," she says, "they literally scare themselves to death."

Constant worrying causes cortisol and epinephrine levels to rise - and these stress hormones can weaken the body's overall immunity. "The immune system plummets when cortisol levels are chronically high," she says. "Your own body produces high levels of steroids when you're under constant stress."

Up Your Vitamin Intake

We have a worldwide epidemic of vitamin D deficiency, says Northrup. Everybody needs vitamin D, which can be found in foods like sockeye salmon, eggs, and milk.

Hyla Cass, MD, an integrative medical practitioner and author of 8 Weeks to Vibrant Health, adds that certain prescription drugs like acid blockers can deprive the body of nutrients like vitamin D.

Surveys show that Americans don't get enough vitamin C, says Elisabetta Politi, RD, MPH, CDE, nutrition director at the Duke Diet & Fitness Center.
Citrus fruits are a good source of vitamin C. "It's a myth that vitamin C prevents the cold," she says. "But having an appropriate amount of vitamin C from fruits and vegetables can boost immunity."

Mind Over Body

Atlanta interior designer Melissa Galt believes in a "mind over medicine" attitude. "I don't have time for sickness in my life," says Galt, who travels frequently and doesn't take anything to fight germs. "I don't believe in it and don't acknowledge it."

Every thought is accompanied by a chain of biochemical reactions in your body, says Northrup. So a positive attitude can increase levels of nitric oxide, which help to balance neurotransmitters, improve immunity, and increase circulation, she says.

"Whenever nitric oxide levels are high - from anything ranging from positive thought to exercise - you're actually improving your resistance to disease," she says.

Just Say Om

Santa Monica, Calif., yoga therapist Felice Rhiannon credits her meditation and breathing practices for improving her physical and emotional health. "Meditation practice helps to calm my nervous system and allows the immune system to function with less interference," she says. For Rhiannon, "A calmer mind means a calmer body."

"The greatest change is in my peace of mind and sense of ease," she says. "I don't get colds as often as I did when I was younger. My sleep is better and my ability to cope with life's inevitable stresses has improved."

In a study published in the journal Psychosomatic Medicine in 2003, researchers at the University of Wisconsin and Harvard University found that volunteers who participated in eight weeks of mediation training produced significantly more flu-fighting antibodies than those who didn't meditate.

Increase Your Social Ties

There are personality factors associated with individuals who are resistant to getting colds when they're exposed to a virus, says Sheldon Cohen, PhD, professor of psychology at Carnegie Mellon University whose research examines the effects of stress and social support on immunity and health.

For example, extroverts are less likely than introverts to get colds when exposed to a virus. "We actually control for their immunity," he says.

"The explanation isn't that extroverts interact with more people, and therefore have immunity to that virus. There's something about being extroverted that seems to protect people."

Having a diverse social network is equally important, says Cohen. Individuals who belong to multiple social groups are less likely to develop colds when exposed to a virus. There's convincing literature in epidemiology that people who have more diverse social networks are also less likely to get heart disease and live longer, he adds.

Accentuate the Positive

Cohen's research suggests that people who have a positive emotional style - described as happy, enthusiastic, and calm - are less likely to catch colds.

Cohen and researchers at Carnegie Mellon University interviewed 193 healthy adults daily for two weeks and recorded the positive and negative emotions they experienced each day, and then exposed the volunteers to a cold or flu virus. Those with positive outlooks reported fewer cold symptoms and were more resistant to developing an upper respiratory illness.

"It's a stable characteristic of individuals," he says. "It's not driven by how happy they are on the day they get exposed to the virus."

Wash Your Hands - Over and Over

Hand washing may sound like obvious advice for combating germs, but surveys suggest that most of us are not vigilant about washing our hands after using the restroom.

"In order to prevent illness, it's important to wash your hands frequently," Cass says. "During cold and flu season, wash your hands with soap many times during the day because you're in contact with all kinds of pathogens - door knobs, stair railings, other people. You really want to have clean hands."

According to the CDC, proper hand washing for 20 seconds is the most effective way to avoid the 1 billion colds that Americans catch each year, not to mention other infectious diseases.

Get Your ZZZs

Sleep is one of the best ways to stay healthy, Northrup says. "People who get a solid eight hours per night absolutely do better."

Sleep efficiency is the key, Cohen says. People who get into bed and fall asleep right away and stay asleep are more protected against colds than those who wake up repeatedly through the night.

A good night's sleep will restore the immune system, Northrup says, because when you get a good night's sleep, melatonin levels rise and that improves immunity.

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