

Picture of a guy losing brain cells on White Mountain
Are the Mountains Killing Your Brain? Alarming new science shows that thin
air can wreck brain cells—at lower altitudes than you'd think. Here's how to
protect yourself.
"YOU HAVE TO BE poco loco to be a climber," says
Dr. Nicholás Fayed. A neuroradiologist at the Clinica Quirón de Zaragoza, in
northern Spain, Dr. Fayed leads me into his office and pulls out a
collection of MRI images. They're brain scans, taken from amateur and
professional mountain climbers after they came back from major expeditions,
and the results aren't pretty.
"Atrophy of the frontal lobes," Fayed
says, pointing to a black-and-white slice of brain on one MRI. The frontal
cortex—the region just behind the forehead that handles higher-level mental
functions—looks like a piece of dried fruit. This kind of damage can leave
patients with an impaired ability to plan, focus, and make complex
decisions. And it's permanent.
SCIENTISTS HAVE long known
that the brain can be harmed by extreme conditions such as high-altitude
cerebral edema (HACE), in which blood vessels leak fluid into surrounding
tissue, causing the brain to swell and press against the skull wall. But
Fayed's scans are the first to indicate that brain damage can show up even
in people who displayed no symptoms of altitude sickness during their
climbs, or had just the usual nausea and lethargy familiar to any hiker in
the mountains. And, disturbingly, it seemed to happen to climbers going not
much higher than 15,000 feet.
One trekker had cortical
atrophy—a permanent loss of gray matter that can cause "spaciness" and other
problems—and one had a subcortical lesion, damage to the network of neural
pathways in the white matter, which can cause any number of serious
issues.
The amateurs on Aconcagua gave themselves six days of
acclimatizing for that 9,000-vertical-foot climb (as opposed to the two to
three weeks taken by commercial teams), and every brain scan showed
problems. (A second scan three years later showed no improvement.) Overall,
five of the 23 amateurs
the Spaniards studied had irreversible subcortical
lesions—the most serious brain injury the team found. None of the 12
professionals had them.
What is still unclear is how high you
have to go, or how fast, before your neurons start dying en masse. The
greatest risk lies above 15,000 feet, but there's no reason to assume it
can't happen lower.
Protect Your Brain
Follow these
steps to prevent high-altitude trouble in your head.
1. Coming from sea
level? Spend night one at about 5,000 feet.
2. Ascend as slowly as
possible. Medically speaking, the safest rate is
1,000 feet per day above
9,000 feet.
3. Minimize time above 19,500 feet.
4. Climb high,
sleep low. The higher elevation will kick-start the
acclimatization process,
while descending at night allows the body to adapt
at a safer elevation. Or
build in a rest day every 2-3 days.
5. Listen to your body. Never ascend
with obvious symptoms of altitude
sickness; descend if symptoms
worsen.
6. Stay hydrated, avoid excess salt, and eat foods rich in
carbohydrates.
7. Don't drink alcohol—it's dehydrating and depresses
breathing.
http://outside.away.com/outside/bodywork/200910/mountains-thin-air-brain-cells-intro.html?utm_source=Outside&utm_medium=email&utm_campaign=DispatchThanks to Tom Chester