Janet Yellen just told Ralph Nader to back off.

Nader, a former presidential candidate and activist, criticized Yellen and the Federal Reserve in October for keeping interest rates near zero since December 2008.

Nader's advice: talk to your husband, he probably knows better.

"Chairwoman Yellen, I think you should sit down with your Nobel Prize winning husband, economist George Akerlof, who is known to be consumer-sensitive," Nader, 81, wrote in an open letter published in the Huffington Post.

Nader also recommended that Yellen -- the Fed's first female Chair -- speak to one of her former male colleagues at the University of California, Berkeley, to get a better grasp on her job.

Nader's central criticism is that American savers haven't earned any interest in the last six years.

Related: U.S. economy grows at better than expected pace

In a rare response, Yellen fired back with her own public letter to Nader, where she doesn't address his advice on seeking help from her husband or her male colleagues.

Instead, Yellen starts by thanking Nader for his letter. She then jumps very quickly to her point: "It may help to review a few basic facts."

She strongly defends the Fed's actions during and after the financial crisis.

"Low interest rates supported the economic recovery and the creation of millions of jobs," Yellen writes.

Related: Fed to America: Get ready for higher interest rates

Yellen says savers would not be better off today if the Fed hadn't kept rates so low for so long.

"Unemployment would have risen to even higher levels, home prices would have collapsed further, even more businesses and individuals would have faced bankruptcy and foreclosure," Yellen argues.

All those would negate any gains savers would see from higher interest rates on bank deposits, she says.

As Yellen points out, low rates have encouraged spending by consumers and borrowing by businesses. And the unemployment rate has gone to 5% today from 10% in 2009.

It's no secret that the Fed is getting ready to raise interest rates for the first time in nearly a decade.

But for now, Yellen appears to have no regrets about seven years of near-zero interest rates.