Grey matter shrinks `without water`

Last Updated: May 20, 2010, 00:00 AM IST

London: Make sure you drink enough water
everyday -- it`s not only good for your body, but it is good
for your brain too, for a new study says that grey matter can
shrink without hydration.

Researchers have found that failing to drink enough
water can make grey matter shrink, making it harder to think
-- so, dehydration not only affects the size of the brain but
also how it works, the `Daily Mail` reported.

According to them, just 90 minutes of steady sweating
can shrink the brain as much as a year of ageing.

Starved of water, the grey matter is also forced
to work harder to process the same information. Over days and
weeks, lack of fluid could impact on performance at work and
school, and on exam results.

But there is no need to panic -- because after a glass
of water or two the brain quickly returns to normal, say the
researchers at King`s College London.

For their study, the researchers scanned the brains of
teenagers after an hour and a half of cycling. Some exercised
in three layers of sweat-inducing clothing -- a binliner worn
next to the skin, a hooded chemical warfare suit and a track
suit. Others were more lightly clad in shorts and t-shirts.

Those who were wrapped up lost around two pounds
in sweat - and their brain tissue had shrunk away from their
skulls, the study found.

Lead researcher Matthew Kempton said: "We saw a
general shrinking of the brain tissue. Fluid filled cavities
in the middle of the brain expanded and there was a
corresponding shrinking of the brain tissue. The people who
lost the most weight had the most shrinkage of the brain."

On average, the amount of shrinkage equated to 14
months of age-related wear and tear, or the withering away
associated with two and a half months of Alzheimer`s disease.

The sweaty students did just as well when asked to
play a computer game that tests the ability to plan and solve
problems. But the scans showed they used more of their brains
to do it, according to the findings published in the `Human
Brain Mapping` journal.

PTI