It’s said that looks don’t matter. But apparently they matter very much to Donald Trump — and if you aren’t thin and good-looking, you are not worthy of a vote or much else.

We were reminded of that in spades during Monday night’s presidential debate at Hofstra University. NBC moderator Lester Holt asked Trump why he said Hillary Clinton doesn’t look presidential.

He fumbled. Tried to disseminate. But Holt stuck to it. Trump did say it.

Then Clinton later brought up the way Trump has weight shamed a former teenage Miss Universe, Alicia Machado, calling her “Miss Piggy” and “Miss Housekeeping” and describing her to radio host Howard Stern as an “eating machine.”

And Rosie O’Donnell came up too. He’s said she’s “a degenerate,” “a slob,” “a fat, ugly face” and more. When Clinton called him on this, Trump’s response was to reinvigorate a feud that dates back to 2006. It was not to apologize but to say O’Donnell “deserved it.”

Maybe Trump is aware of disturbing research suggesting that people vote at least in part on how a candidate looks.

Another formidable woman who doesn’t score high on Trump’s “She’s-a-10 Meter” is former Republican presidential candidate Carly Fiorina. You remember: “Look at that face! Would anyone vote for that? Can you imagine that, the face of our next president?!”

Americans are notoriously shallow in evaluating one another; maybe Trump is aware of disturbing research suggesting that people vote based at least in part on how a candidate looks.

Trump’s recent foray in front of an audience of a reported 84 million did him no favors with women. It’s likely he further eroded his already-low female support. Before the debate, 64 percent of women had an unfavorable response to Trump. Among likely voters, Clinton dominates Trump in overall support by a whopping 51 percent to 34 percent, according to the Associated Press.

A quick post-debate poll by Public Policy Polling Monday night showed Clinton winning the exchange by a wide margin of 54 percent to 36 percent among women polled.

Maybe it was that she was better prepared. Or wasn’t easily rattled. Or has more in-the-trenches experience as a first lady, US senator and secretary of state.

But there’s no doubt that Trump’s bullying, shouting, smirking, talking over and continuous interrupting struck a chord with women who for too long have put up with men in work settings, if not at home, doing the same thing.

Vox pointed out in a tweet at 9:26 p.m. that Trump had interrupted Clinton 25 times. The final count for the 90-minute-plus debate was more than twice that.

Trump interrupted Clinton 51 times during Monday night's presidential debate. She interrupted him just 17 times. https://t.co/y38KqLBH6f — Vox (@voxdotcom) Sept. 27, 2016

When Trump wasn’t trying to rudely speak over her, he was faux-whispering into the mic while she was talking: “Wrong. Wrong. Wrong.”

Clinton’s campaign manager, John Podesta, was quick to point this out, with a nod toward a key constituency.

“His constant interruption of her probably was reminiscent of the way a lot of women feel about bullies in their lives,” he said. “I thought it was kind of unbecoming and he couldn’t stop himself.”

Right from the beginning, Trump came across as condescending. What should he call her? He asked for faux permission to use her former title, all of which was designed to call attention to the fact that he was acknowledging her role as secretary of state. Instead of coming off as respectful, the way he handled it was demeaning.

“Secretary Clinton, is that OK? Good. I want you to be very happy. It’s very important to me,” Trump said. Of course it was better than “Crooked Hillary,” what he calls her out on the campaign trail. She referred to him repeatedly as “Donald.”

But she bested in him in what was clearly an orchestrated moment designed to set off a media bomb. By raising the case of Machado and Trump’s public humiliation of her, Clinton turned the 1996 Miss Universe into a household name. It was media catnip: The New York Times reported that since the debate, Machado’s name has appeared on TV 6,023 times and nearly 200,000 times on Twitter!

As Clinton undoubtedly surmised, Machado has come to represent millions of women who worry about their weight, fret over their looks and feel harshly and unfairly judged by measures that undermine their brains, their talents and their determination.

You would think that since so many women empathized with Machado and are rallying behind her, Trump might have changed his tune, admit that his criticisms were sexist and cruel, repent and beg for forgiveness.

But that wouldn’t be Trump. No, instead he called in to Fox News the day after the debate to explain himself. “She gained a massive amount of weight,” he said. “It was a real problem.”

It might turn out that Alicia Machado is a real problem. But not the one he was talking about.