The Washington Post (NYSE:WPO) reported Sunday that Stewart, who was among the first to demand health warnings be placed on cigarette packs, died of kidney failure at Ochsner Medical Center.

In addition to his anti-smoking efforts during his term between 1965 and 1969, Stewart used his influence to bring attention to racial discrimination in the U.S. healthcare system.

"On one side of the curtain is the gleaming, antiseptic world of medical excellence," he said in a 1967 speech. "Its wonders are plainly visible to those outside. But admission is by ticket only, and the line to the box office stretches out of sight."

Stewart also used the introduction of Medicare in 1965 to desegregate hospital beds nationwide, tying the healthcare effort to the Civil Rights Act of 1964.

The Post said Stewart, who died last Wednesday, is survived by his wife Glendora, two daughters and five grandchildren.