Wednesday, 26 December 2007

The seven great medical myths

Reuters: - Reading in dim light won't damage your eyes, you don't need eight glasses of water a day to stay healthy and shaving your legs won't make the hair grow back faster.

These well-worn theories are among seven "medical myths" exposed in a paper published Friday in the British Medical Journal.

Despite frequent mentions in the popular press of the need to drink eight glasses of water, researchers found no scientific basis for the claim.

The other six "myths" are:

*Reading in dim light ruins your eyesight

The majority of eye experts believe it is unlikely to do any permanent damage, but it may make you squint, blink more and have trouble focusing.

*Shaving makes hair grow back faster or coarser

It has no effect on the thickness or rate of hair regrowth, studies say. But stubble lacks the finer taper of unshaven hair, giving the impression of coarseness.

*Eating turkey makes you drowsy

It does contain an amino acid called tryptophan that is involved in sleep and mood control. But turkey has no more of the acid than chicken or minced beef. Eating lots of food and drink at Christmas are probably the real cause of sleepiness.

* We use only 10 percent of our brains

This myth arose as early as 1907 but imaging shows no area of the brain is silent or completely inactive.

* Hair and fingernails continue to grow after death

This idea may stem from ghoulish novels. The researchers said the skin dries out and retracts after death, giving the appearance of longer hair or nails

*Mobile phones are dangerous in hospitals

Despite widespread concerns, studies have found minimal interference with medical equipment.


ISK said...

Another myth which i have closely noticed is that "Having tea before going to bed causes sleeplessness."

But as far as I am concerned I have never experienced such problem
rather i prefer taking tea before going to bed and most of the times
it makes me more sleepy and drowsy.

But Yes if the tea is hopeless then it will for sure cause sleeplessness.

Syra said...

:) I share similar views regarding coffee.It doesn't spoil my sleep.
Me not a tea fan. But i have seen my friends light up after a cup of tea.

teeB@ said...

this para shows tht still all dez myths r true....!!!

khany said...

i once set about compiling a list of common myths that mothers (or parents in general) pass down to their children...

surprisingly, or may be not so surprisingly, 2 of the items on my list made it to the top 7 medical myths!

my list in no specific order was as follows:

1. eyesight deteriorates due to reading in poor light.
children instinctively find it hard to accept with good reason.

everybody understands that while a camera does not work too well in the dark yet it is not 'damaged' if used under dim lighting. given that the camera is an accepted model for the eye this should already start raising red flags in one's mind.

second, for centuries men of learning would study through the night by the aid of a solitary candle. we were never passed down any information that they were more inclined to lose sight relative to their peers.

finally, consider also that part of the eye is a muscle. working a muscle often leads to signs of fatigue and aching. anybody who has spent a night watching a movie marathon can tell you that the same is true for the eye muscle as well.

we would find it preposterous if somebody suggested to us that we would damage our limbs if we worked them to the extent of fatigue. in fact many of us specifically strive to work our muscles to aching at gym in an effort to tone them. why, then, do we accept this argument for eyes?

2. eyesight deteriorates when viewing tv at close range
this is an excellent web page that debunks several eye related myths.

i formulated a narrative that could explain the acceptance of this myth as part of common wisdom. it goes as follows.

back in the day when television was newly introduced to the unwary public no such myth existed. mothers would blissfully allow their young ones to watch tv from whatever distance they willed. soon, however, mothers across the society began to note a disturbing trend. they observed that those of their young children who sat up closest to the television screen grew up to have poor vision. the obvious explanation is that the television is somehow responsible.

when we see that a city with high crime rate has a relatively large police force, we do not immediately conclude that the police is responsible for the crime (at least in countries outside pakistan this is not the first thought that crosses the mind :p). correlation does not imply causation. a simpler explanation would be that those children were sitting up close to the television in the first place because they had poorer vision and not the other way round!

... this is turning into a very long comment so i will cut it off here...

Syra said...

Khany,Thanks for the insight.
Which else myths do you have on your list?
and hey, thinking that Pakistani's immediately mark correlation as causation is a myth itself. :)

khany said...

salam syra,
i will send them to you via email soon inshallah.

i apologize if my comment suggested i was targeting pakistanis. in fact these myths are global. the reference to pakistani police was a joke.

a myth, i believe, is a popularly held set of beliefs which need have no basis in reality. since the above mentioned views are only to my knowledge only held by myself i think they fail to qualify as myths :)

Syra said...

sure, thanx :)