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Somebody recently told me that climbing a Fourteener kills brain cells because of the low oxygen levels. Is this true?
Submitted by – Terry, Colorado Springs, CO
Medical researchers are pretty sure that exposure to altitudes above 15,000 feet causes some brain-cell damage (such as lesions or atrophy), resulting in either short-term or long-term loss of neurocognitive function. But the impact is small enough that most climbers don’t notice a cognitive loss. Still, we don’t know if the damage raises dementia risk down the road.
As for whether any damage occurs in the brain below 15,000 feet, that is unknown, so I can’t say anything definitive. But I doubt you need to worry about brain damage on Fourteeners if you acclimatize properly (meaning not gaining more than about 1,500 to 2,000 feet per day until your body has adapted). A 2006 Spanish study (albeit on people at 15,770 feet or higher) found that proper acclimatization reduces the brain-damage risk.