Wednesday, May 16, 2007

Healthy Habits That Aren't

Using anti-bacterial soap

You may be tempted to take a biological jackhammer to every microbe that dare touch your family, but the fact is there’s a lot we don’t know about the long-term effects of common, household use of anti-bacterials. According to the Centers for Disease Control, these chemicals have been shown, in the lab, to kill off only weak bacteria—leaving the tougher ones to reproduce. That’s led many medical experts to worry that anti-bacterial soaps might be contributing to the rise of stronger bacteria, capable of fighting off our attempts to kill it. So far, this theory hasn’t been proved in a real-life setting. What has been proved, however, is that washing your hands with anti-bacterial soap isn’t anymore effective at preventing disease than hand washing with regular soap. First reported in a 2004 study, published in the journal Annals of Internal Medicine, this discovery led a Food and Drug Administration Expert Advisory Council to announce the next year that there was no proof anti-bacterial soaps lived up to their advertising claims. Bottom line: It’s just not worth the risk.

Sitting up straight
According to a study presented in 2006 at the annual conference for the Radiological Society of North America, so-called “perfect” posture might actually be contributing to back pain. Go ahead, call your mom and gloat. But make sure you get your facts right. When this story first came out last November, many newspapers incorrectly reported that slouching was the better way to sit. The problem turned out to be a “slanguage” barrier. In England, where the story was first reported, “slouching” refers to reclining backward, which is, according to the study, a great way to relieve pressure on your lower back. Translated into American slang, however, the news reports gave many people the impression that hunching forward was healthy, when, in fact, it’s actually worse than sitting up straight.

Following a low-fat diet
Significantly cutting the fat in your diet is supposed to lead to weight loss, cancer prevention and a healthier heart. Turns out, those promises might just be empty intellectual calories. In 2006, the Women’s Health Initiative—a several-billion dollar, eight-year study of the effects of low-fat diets—finally came to an end. The results were shocking. Not only did the women who followed “fat-free diets” show no decrease in cancer or heart disease rates compared to their fat-eating counterparts, but they also weren’t any skinnier. And, the researchers said, the study probably applied to men as well. If you follow the medical literature, however, there’ve been plenty of studies, dating back to the early 1990s, which show low-fat diets aren’t as effective as they’re made out to be. In fact, there’s even some evidence that the behaviors they inspire might be harmful. A 2007 study in the journal Human Reproduction found that women who carefully avoided full-fat dairy products were more likely to experience a certain type of infertility.

Trusting your eyesight to carrots
If you think these vegetables will improve your vision, think again. While carrots do contain vitamin A, which is a major player in keeping your eyes working properly, you really only need a small amount of it—and no matter how much vitamin A you consume, it’s not going to magically eliminate your need for glasses. In fact, if you eat too much vitamin A, you can end up with a toxic—although not usually fatal—reaction. The idea that more carrots means better vision might actually be a relic of a World War II-era military disinformation campaign. According to the online World Carrot Museum, British intelligence began spreading the myth during the blitz as a plausible explanation for why their fighter pilots were suddenly able to spot Nazi planes at night. In reality, the British had simply developed a better radar system and didn’t want the enemy to find out about it.

Taking antioxidant supplements
They’re supposed to reduce your risk of cancer and heart disease and even diminish the effects of aging, but, if you take antioxidants as a pill or some other drug-like form, chances are they aren’t doing anything at all. The basic idea behind the hype is that antioxidants, chemicals found in fruits and vegetables, can help reduce damage to various parts of your body by balancing unstable chemicals known as free radicals.

Without antioxidants, free radicals start trying to stabilize themselves—often by swiping molecules from your DNA, damaging it in the process. So far, so good. The free radical-fighting power of antioxidants has been demonstrated in the lab and people who eat plant-heavy diets are less likely to suffer from the diseases linked to free radicals. But, as Dr. Lisa Melton wrote in an article in the August 2006 issue of New Scientist magazine, many studies have shown that people who get their antioxidants from popular supplements receive none of the health benefits. In fact, Melton cited a few studies that even suggested antioxidant supplements were leading to worse internal damage, including a 1992 study by the National Cancer Institute that had to be cancelled after the patients taking beta carotene supplements actually began developing higher rates of lung cancer than those taking sugar pills.

Drinking eight glasses of water a day
Admit it, this is one healthy habit that’s a royal pain. Luckily, it’s also completely unnecessary. For some people, eight glasses a day might actually be far too much, leading to sodium deficiencies and potentially life-threatening water intoxication, caused by kidneys not being able to keep up the intake of liquids. In 2002, a kidney specialist tried, in vain, to find any scientific evidence supporting the eight-glasses-a-day myth. His report, published in the American Journal of Physiology, concluded that this standard health advice was complete and utter bunk that, like many urban legends, stemmed from a tiny grain of truth. Apparently, the dietary guidelines provided by the Food and Nutrition Board of the National Research Council do say that humans need 1 milliliter of water for each calorie of food—adding up to about 10 cups a day. However, the same guidelines also say that we get most of this liquid from the water in solid food. There’s no need to drink more.

Buying “all-natural” health products
Certain natural health products and supplements might have some value, but the label “all-natural” doesn’t necessarily mean “safe.” Don’t feel too bad if you’ve leapt to that conclusion, though. It’s such a common mistake that the Canadian National Health Network began an education program aimed at making sure consumers were aware of the risks inherent in natural health products. According to the CHN, some natural health products might be toxic if you take too much, others can trigger unexpected allergic reactions, and still others react badly with medically prescribed drugs or with individual health issues, like pregnancy or heart disease. And, while the CHN reviews and labels natural health products for safety, most of the ones in the U.S. haven’t been tested or proven effective. They can be sold as long as they don’t claim to be able to treat or cure a specific disease. The best thing to do, before you start taking any supplement or look into any alternative cure, is to talk to your doctor. He or she will be able to help you make the best decisions for your body.

Relying on sunscreen to save you from skin cancer
Why is this healthy habit a bust? Because you’re probably doing it wrong. According to Dr. Francesca Fusco, spokeswoman for the Skin Cancer Foundation, people tend to not use enough sunscreen or use it consistently or use it early enough in life; they also often aren’t using a sunscreen that’s truly effective. Some of her tips for proper use include: Putting sunscreen on over any medication but under makeup; using the equivalent of a shot glass or two to cover your whole body—even under clothes—and then waiting at least 30 minutes before you go outside; and always using a sunscreen that contains the ingredient mexoryl. That last one is a biggie. Sunscreens without mexoryl—which is, to say, most of them—only protect against UVB wavelengths of light. But UVA waves are dangerous as well—possibly more so, considering that they can damage your skin without causing sunburn, leaving you unaware of your risk.

By Maggie Koerth-Baker for MSN Health & Fitness

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