Saturday, December 22, 2007

'Medical myths' exposed as untrue

Our friends at the BBC report that [some] "claim drinking eight glasses of water a day leads to good health, while reading in dim light damages eyesight.
Others believe we only use 10% of our brains or that shaving legs causes hair to grow back thicker.
But a review of evidence by US researchers surrounding seven commonly-hold beliefs suggests they are actually "medical myths".
Some are utterly untrue, while others have no evidential proof, the British Medical Journal reports.
Researchers from the Indiana University School of Medicine in Indianapolis hunted medical literature for evidence on each claim.
They found no evidence supporting the need to drink eight glasses of water a day.
In fact, studies suggest that adequate fluid intake is often met by drinking juice, milk, and even caffeine-rich tea and coffee.
Data also suggests drinking excessive amounts of water can be dangerous.
The belief that we only use 10% of our brains appears to be completely untrue.
Studies of patients with brain damage suggest that damage to almost any area of the brain has specific and lasting effects on mental, vegetative and behavioural capabilities.
Brain imaging studies also show that no area of the brain is completely silent or inactive.
And the belief that hair and fingernails continue to grow after death may be an optical illusion caused by retraction of the skin after death. The actual growth of hair and nails requires a complex interplay of hormonal regulation not present after death.
Again, illusion may be to blame for the belief that shaving hair causes it to grow back faster, darker, and coarser, report author Rachel Vreeman told the BMJ.
The stubble resulting from shaving grows out without the finer taper seen at the ends of unshaven hair, giving the impression of thickness and coarseness.
Again, expert opinion is that reading in dim light does not damage your eyes. And there is little evidence to support the banning mobile phones from hospitals on the basis of electromagnetic interference.
Finally, eating turkey - and the tryptophan amino acid it contains - does not make people especially drowsy.
Indeed, turkey, chicken and minced beef contain similar amounts of tryptophan.
The researchers explained: "Any large meal can induce sleepiness because blood flow and oxygenation to the brain decrease, and meals rich in protein or carbohydrate may cause drowsiness. Wine may also play a role."
Dr David Tovey, editor of Clinical Evidence journal, said: "The difficulty is it is often hard to disprove a theory.
"On the flip-side, absence of evidence does not necessarily mean absence of effect.
"Where reliable evidence becomes really important is in helping people make serious decisions about harms and risks.
"Many of these 'myths' are innocuous. However, we are still finding evidence that runs contrary to current practice and what we expect."..."


bluedreamer27 said...

i never knew anything about this
although in my school they always include those beliefs as "healthy habits"
but i never thought that it would lead to those effects
i do believe that that "healthy living is on the doctor eye"
never trust what you believe and only based upon your opinion
even other beliefs are not apllicable to have a healthy living
doctors are trained so they knew everything that is good for us
but how about "an apple a day makes doctors away?
hmmmmmm is it a supestitious belief or there is something scientific explanatory behind

Debbie said...

I think a lot of this is "old wive's tales" that have been accepted and passed down as truth through the years.

Debbie Hamilton
Right Truth

Nezha said...

I always thought that drinking 8 glasses was good for you. I guess that's what happens when you don't check the medical facts!

mellowed blues said...

I've always believed that carrots are good for your eyes. That's why rabbits never wear glasses.

Titania Starlight said...

That is so true about the water being a myth. When my husband went to a urologist for kidney the stones his exact words that bottled water is the best scam they ever came up with along with the eight glasses deal. He said your body could care less about what liquid is coming in as long as it is coming in. It may take a long time for people to believe this just like when they once said the world was flat. I tend to think outside of the box so I am willing to debunk old wives tales. :o)~

Great post!

The All Seeing Eye said...

I am in the same boat w/you, Bluedreamer27. I had not heard of all of these before I read the article.

The All Seeing Eye said...

You're right, Debbie. It does help to test these tales because they could suggest dangerous behavior.

The All Seeing Eye said...

Well Nezha, I will continue drinking a lot of water during the day. I feel better when I do. Plus it's better than drinking a soda.

The All Seeing Eye said...

Yes Mellowed Blues, Bugs Bunny never needed glasses...

The All Seeing Eye said...

I am glad you liked the post, Titania. When I saw the story, I knew I had to put it in my blog. I will still drink water as I do. I never gave into the bottle water industry. Why should I pay $2 for a bottle of water? I am not living in the dessert.