Dying from low salt

This NY Times article says that athletes can die from a lack of salt:

The research involved 488 runners in the 2002 marathon. The runners gave blood samples before and after the race. While most were fine, 13 percent of them - or 62 - drank so much that they had hyponatremia, or abnormally low blood sodium levels. Three had levels so low that they were in danger of dying.

When I was a kid, athletes were commonly given salt pills during water breaks. The article fails to suggest or even mention this obvious remedy.

We've had many years of propaganda that salt is somehow unhealthy or harmful. Salt is a health issue for a small number of people on high blood pressure medication, but the vast majority of people can eat all the salt they want with no known ill effects.