By Sam Blanchard Health Reporter For Mailonline
Published: 14:05 GMT, 15 March 2019 | Updated: 15:05 GMT, 15 March 2019
You may think the white specks on your nails come from a lack of calcium or shutting your finger in a drawer.
But one 27-year-old man was left with matching lines across all his fingernails – because he climbed a mountain.
The unnamed climber, from Newcastle, visited a doctor because he was worried about the mysterious lines which appeared after his trip.
And he was told the harmless condition had be caused by oxygen deprivation during his mountaineering holiday.
The unnamed climber, 27, was left with matching white lines running horizontally across all his fingernails. His doctor told him the condition – called Mees' lines – was caused by a lack of oxygen while he was climbing a mountain
He was diagnosed with Mees' lines, which are lines of white discoloration that run horizontally across nails.
He had no other injuries or medical conditions which could have explained them, and his doctor realised they had been caused by the altitude.
The man had climbed almost to the summit of the mountain Spantik, in Pakistan, which is 7,031metres high – 80 per cent of the height of Mount Everest (8,850m).
And spending three weeks at altitudes of 4,000m or more is what triggered the strange-looking occurrence, according to an article in BMJ Case Reports.
Unfortunately, he never made it to the summit, turning back after 6,900m because of exhaustion and hypothermia.
But spending so long at altitude deprived his fingers of the oxygen needed to grow healthy nails, his physician Dr Avinash Aujayeb said.
He said being at high altitude could starve the body of minerals and reduce blood flow to the extremeties.
'A wide variety of nail