Drinking too much water can be deadly. That’s that latest, surprising word from doctors who question marathon runners’ tendency to drink often during races.

CBS News reports that marathon runner Frederic Lecao had experienced cramps during races in the past and wanted to do everything he could to avoid that again.

“I was literally taking a sip every five minutes,” said Lecao.

But when it came to staying hydrated, he overdid it and suffered severe consequences.

“I was literally on the ground screaming in pain,” he said. “My whole body shut down,” he said.
What he suffered from is called hyponatremia, a dangerously low level of sodium or electrolytes in the blood, said Scott Weiss, M.D.