Des Moines, Iowa CNN  — 

Democratic presidential candidate Bernie Sanders says the United States should have a “serious national discussion about sexuality” – not run away from it.

The Vermont senator’s comment came in response to a question during Monday night’s Iowa Brown and Black Forum at Drake University about whether schools should teach students about affirmative consent before sex.

READ: Sanders distances himself from ‘dumb’ 1972 essay

“We really do need a serious national discussion about sexuality,” Sanders said.

He also said that “rape must be prosecuted” in response to a question about rape on college campuses.

And he told Molly Monk, a Simpson College student and Democratic activist, that he opposes abstinence-only education.

“When sexuality is an intrinsic part of human life – we should not run away from it,” Sanders said. “We should explain biology and sexuality to our kids on a factual basis. Period.”

Sanders hasn’t often commented on sexuality after a 1972 essay – in which he wrote a woman “fantasizes being raped by three men simultaneously,” among other things – caused controversy in May.

Sanders spokesman Michael Briggs said at the time that the essay was a “dumb attempt at dark satire in an alternative publication” and doesn’t reflect Sanders’ views on women.

“It was intended to attack gender stereotypes of the ’70s, but it looks as stupid today as it was then,” Briggs said in May.