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7 Solid Health Tips That No Longer Apply

Runner's Knee: Not for thee

Many doctors, while advocating for exercising in general, have recommended swimming and walking over running because of the assumption that running would ultimately destroy your knees. New studies reveal, however, that not only is runner's knee avoidable, running can protect the knees.

One study was published last year in Skeletal Radiology, causing a bit of a stir. The study was a ten-year followup of 1997 Vienna marathon runners. Of the eight runners followed, only one had knee problems. But that one person had knee problems before the 1997 marathon and had stopped running. The rest, all middle-aged males, were still running long distances pain free.

Similarly a Stanford University study, also published last year, followed runners in their 50s and 60s for over 20 years. At the beginning of the study, about 7 percent of the runners had sore knees. Twenty years on, their knees were healthier. That's zero percent of the runners with bad knees compared to 32 percent in the control group, which started the study with healthy knees.

None of this suggests that runners can't damage their knees. That damage, however, is usually caused by a non-running injury or by running poorly. Once damage sets in, the body might overcompensate by changing the stride. Then, like an unbalanced tire worn thin, the knee cartilage can wear away quickly.

Suntan: Popularity is fading

There's no such thing as a healthy tan. Most cultures throughout the ages tried their best to protect themselves from the sun. All that changed, however, in the enlightened era of the 20th century.

By the early 1900s, scientists discovered that ultraviolet light or sunlight, which contains ultraviolet light, could cure rickets, a disease characterized by weak and deformed bones as a result of a vitamin D deficiency. Also, the Icelandic-Danish scientist Niels Ryberg Finsen won the 1903 Nobel Prize in Medicine for his work on phototherapy, in which light of various wavelengths is used to cure disease. This set the stage for sunbathing and, in particular, deliberate suntanning with suntan lotions.

Today it is clear that ultraviolet radiation causes skin cancer. In fact, as of this year, the sun has joined the ranks of tobacco and asbestos in the highest-risk category of agents that cause cancer. No longer is ultraviolet radiation a probable carcinogen. It is a carcinogen, period. This applies to tanning booths, long thought to be reasonably safe because the radiation used is lower-energy ultraviolet A, or UVA.

A little sun is needed for vitamin D generation. How little is too much is hotly debated.

Eating healthy: Don't get carried away

Nothing's wrong with eating healthy, right? Well, there are limits to everything. In recent years doctors have identified an eating disorder called orthorexia nervosa, referring to the compulsive nature of some health food junkies on a quest to improve their health or cure themselves of some perceived disease.

Some subscribe to extreme diets, such as the raw food diet, and end up with vitamin deficiencies. Others spend exorbitant prices for exotic or organic foods. A sign of an eating disorder is when one develops a maniacal obsession for healthy food to a point at which eating behavior dominates one's life and falling off the diet results in guilt and depression.

Not all doctors are convinced that orthorexia nervosa constitutes a true eating disorder along the lines of anorexia and bulimia. But the rate does appear to be on the rise in this age of heightened awareness of nutrition.

Margarine: From bad to good to bad, bad, bad

Unlike butter, which was developed millennia ago naturally -- albeit after squeezing a goat's or cow's udders to collect her milk, then isolating the liquid fat and agitating it until it turns solid -- margarine was invented in a laboratory by a chemist in 1813. That alone should make you question its healthfulness.

In the early days, margarine indeed was loathed. But this was mainly a result of the dairy industry marginalizing margarine, lobbying for laws to tax margarine or ban its coloring so that it wouldn't look like butter. By the 1960s, though, when cholesterol became a bad word, doctors were recommending margarine over butter because it was naturally cholesterol free. Butter was relegated to the realm of lard and tallow.

Margarine's perceived relative healthfulness compared to butter lasted for several decades until but a few years ago, when we learned that margarine's trans-fat not only raises bad cholesterol but also lowers good cholesterol.

Margarine is trying to stage a comeback. Margarine, after all, is just a generic term for a heavily processed, industrialized, laboratory-made fat product. If you read the label, though, you will find that many of these so-called "smart spreads" now substitute trans-fat with tropical oils like palm, palm kernel and coconut, which are loaded with dumb saturated fat. Even if you can't detect anything bad, remember the rule that these products are heavily processed, and that's always bad.

A wiser choice would be to limit butter or try healthier oils such as olive oil.

Eggs: Deviled but no longer demonized

As the souffle rises and falls, so too do people's opinions about the healthfulness of eggs. In recent decades eggs have been demonized as being loaded with fat and cholesterol to such an extent that doctors were recommending that adults limit consumption to a few per week or else eat those tasteless egg substitutes.

Scaring folks out of their shell was one very strange study published last year in the American Journal of Clinical Nutrition, which found that men -- 21,327 male physicians, to be precise -- who had more than an egg a day were 22 percent more likely to die of any cause. Diabetic egg lovers doubled their risk of dying.

But don't let death scare you. The cholesterol in eggs -- and there's a lot, over 200 mg, or two-thirds your daily recommended allowance -- doesn't seem to have as much effect on blood cholesterol levels as does the saturated fat in butter and meat. Eggs are high in many essential vitamins, minerals and fatty acids, particularly healthy omega-3 fatty acids, depending on what kind of eggs you buy.

Anyway, the egg-equals-death finding wasn't supported by larger studies, such as the Framingham Heart Study and a massive one from Japan. Not all doctors have given the green light to eggs, but more and more are seeing eggs as an essential part of a healthy diet, particularly for vegetarians.

Multivitamins: Don't stop, don't start

One of the greatest health advances of the 20th century was the discovery of the roles of vitamins and minerals. Bye bye, beriberi, a once-common disease caused by a lack of thiamine, or vitamin B1. Simple food fortification efforts and a better understanding of nutrition in general also largely put an end to rickets (low vitamin D), scurvy (low vitamin C), pellagra (low niacin, or vitamin B3), goiter (low iodine) and many more antiquated-sounding diseases.

So, why not load up on all these vitamins by taking one pill each day? Sounds logical, and through the 1990s the medical establishment was recommending this for everyone. Then came big, long studies revealing strange things: high-dose beta-carotene increasing the risk of lung cancer among smokers; high-dose vitamin C fueling cancer in mice exposed to herbicides; vitamin E raising the risk of second heart attacks.

In 2006 the National Institutes of Health proclaimed there's no convincing evidence to support the claim that taking multivitamins is a good idea for the general population. The sage advice today is that you do not really have to stop taking a multivitamin, but there's little reason to start taking one.

Aspirin Therapy: Sometimes not worth the risk

An aspirin a day keeps the doctor away? Apparently not for everyone. If you're healthy, you might want to stick to apples.

A daily, low dose of aspirin can help prevent heart attacks for people with coronary heart disease. Aspirin can even significantly reduce the risk of dying when taken during and after a heart attack. The reason lies in aspirin's ability to keep blood platelets from clumping together, thus preventing or reducing the formation of blood clots.

Aspirin is so inexpensive and effective that some doctors in recent years have recommended a daily dose of about 100 mg, less than a third the normal dose, for anyone to prevent heart disease. But the very large, European-based Aspirin for Asymptomatic Atherosclerosis (AAA) study, among others, suggests this isn't so wise.

Basically, clotting can be good, as when you want to stop bleeding -- such as when a vessel in your stomach or brain starts to bleed. The latter is called a hemorrhagic stroke. As reported at a cardiology meeting last month in Barcelona, Spain, the researchers behind the AAA study found no evidence that daily aspirin can prevent heart disease in folks already healthy. So by taking aspirin, they would seriously increase this risk of a hemorrhagic stroke or internal bleeding with absolutely no benefit to compensate for the risk.

Daily exercise still works at preventing heart disease. Lounging around in Barcelona can't hurt either.