Medical Marvels?: Debunking Health Myths

April 17, 2008 — -- Conventional wisdom sometimes has the best cures for the things that ail us. But as one medical review on antioxidants uncovered, some of our medical cures are more myth than medicine.

"Good Morning America" medical contributor Dr. Tim Johnson tried to separate fact from fiction on some hot-button issues, to find out what's true and what's hype.

Dust Mites and Allergies

Most people with serious allergies and asthma are told they should control dust mites in their house, but evidence suggests that controlling dust mites may not prevent allergies.

A review of 54 trials that looked at dust mite control suggested that it doesn't make a difference. Those trials do not prove that controlling dust mites -- either physically or chemically -- makes a difference in allergy attacks or asthma.

Ripping up the carpet or using chemical products recommended for dust mite control doesn't seem to make much difference, though that will shock those who have tried these measures.

We sent the study to a panel of experts, and their response was that the study might show that dust mite control could make a difference if it is used as part of a larger program, including using air conditioning and keeping your windows closed, washing your hair and clothes at night and keeping pets indoors.

Wrapping your mattress could also be helpful, but if that is your only effort to control dust mites it won't make much difference.

The Truth About Hypoallergenic Cats

There's really a catfight between the company that developed so-called hypoallergenic cats and the experts.

Experts say there's no proof that the cats won't trigger the same kinds of allergies caused by normal felines -- and they are expensive. They range from $6,000 to $10,000, and some exotic breeds of the cats go for as much as $35,000.

Our medical unit looked into the customers' experience and the reaction was mixed. Some people swore by them, but others said they were not working at all.

It might be that there is a placebo effect. If you pay that much money for a cat, you might think it's helping you. The question is still up in the air. We need some more studies before we recommend them to people.

Antibiotics and Sinus Infections

If you have sinusitis or sinus infections, you often have serious pain and a stuffy nose. Very often if there is a colored discharge, a doctor will prescribe antibiotics. The Cochrane Center, a nonprofit organization that studies the effects of health care, reviewed 57 studies and found that antibiotics had little effect on patients with simple cases of sinusitis.

The review suggested 80 percent of participants will improve in two weeks without antibiotics. It is tempting to use antibiotics, which are seen as miracle drugs, but the study said that if you have the garden variety sinus infection you will get by on your own without antibiotics.

If you have recurrent chronic sinusitis, it pays to go to a specialist. Go see an ear, nose and throat doctor if you have a chronic on-going problem.

Antioxidants: The Fountain of Youth?

There is no good evidence that vitamin A, beta carotene and vitamin E prolong life. In fact, they might do just the opposite.

Although initial observational studies seemed to suggest that antioxidants prolong life, randomized clinical trials found evidence that they might produce the opposite effect and increase mortality.

You shouldn't avoid vitamins and antioxidants, though. Just don't take more than the recommended daily allowance without consulting a doctor. Daily vitamins are fine. They are a good safety net for those who are not eating a proper diet. Over that, you are taking a risk.

The recommendation used to be to take 400 units of vitamin E daily, but now we know there is not enough evidence to prove that taking that much provides a benefit, and it might be dangerous.