A Florida doctor who supports Donald Trump says voting for Hillary Clinton may be a sign of low testosterone in men. (Melina Mara/The Washington Post)

Dareld Morris frequently doles out medical advice on his practice's Facebook page, trying to drum up business for his weight-loss clinic.

“Did you know that eating when you are anxious or upset can cause digestive problems?” the Florida doctor asks in one post. Another posits that “brain fog” may point to a hormone imbalance.

His latest advice has a political twist. In a radio ad airing in South Florida, Morris says the persistent urge to vote for Hillary Clinton may be a sign of a troubling lack of testosterone, the steroid hormone that regulates masculine traits.

And, the ad says, the good doctor is here to help.

“Most are not aware of the negative effects low T can have on your mental state, for instance your ability to focus and think clearly,” the ad says.

“So as a community service, I have this special offer: For any guys out there that are thinking of voting for Hillary, I want to offer you a free testosterone test. Just come in and register in my office in Fort Myers or online at my online practice, and let's see if we can help.”

Morris, a self-described Donald Trump supporter whose clinic offers hormone treatments, told South Florida NBC affiliate WBBH that the ad is a joke — and a tongue-in-cheek way to promote his business. But he also told the station the ad was an “experiment” and that he wanted to see if there is a correlation between health and political views.

Fox News correspondent Tucker Carlson picked up on the joke Sunday, when he quipped: “It's science. You can't deny it. Are you a low T denier? Not me.”

Scientists have been studying how genes and hormones affect politics for decades, but the results are inconclusive. One thing that's clear is that political preference is a mix of our genetic predispositions, upbringing and life experiences.

One study said men with wider faces (a sign of higher testosterone) “are more likely to express racist remarks and are less concerned about how others perceive those remarks.”

Another study found that men with more upper body strength are more likely to oppose wealth redistribution.

Morris isn't the first to mention manliness in this political season. The race for president features the first female nominee of a major party and a Republican nominee who used a televised debate to defend the size of his hands and “something else.”

In February, then-candidate Sen. Marco Rubio (R-Fla.) said Trump had unusually small hands. “And you know what they say about men with small hands,” he added.

Trump responded at the Fox News debate a few days later: “And he referred to my hands — if they're small, something else must be small. I guarantee you, there's no problem. I guarantee.”

Last month, Trump commented on Clinton’s appearance, telling ABC's David Muir that she doesn’t have “a presidential look” — a remark that drew a sharp rebuke from Clinton's campaign.

“Well, I just don’t think she has a presidential look,” Trump told Muir. “And you need a presidential look. You have to get the job done. I think if she went to Mexico she would have had a total failure. We had a big success.”

As The Washington Post's Jose A. DelReal reported at the time:

Trump has said regularly on the campaign trail that Clinton does not look presidential, which his critics have blasted as a sexist attack on the first female presidential nominee for a major political party.

When Muir pressed Trump on whether his comments were about her physical “aesthetic,” Trump shrugged — suggesting his disapproval with the question — before knocking Clinton for her attacks on him.

Within hours, Clinton's campaign was working to raise money off Trump's comments.

“Luckily for all of us, a presidential campaign isn't one of Trump’s beauty pageants,” a Clinton aide said in an online fundraising solicitation. “His judgment counts for very little on most things, and even less when the subject is who looks ‘presidential.’”

As Clare Malone said on the Five Thirty Eight post titled “Do you have to be manly to be president”:

This election, particularly on the Republican side, has been a lot more upfront about sexism, gender and, yes, masculinity (see aforementioned penis). Some of that has to do with Republicans’ spinning the race to talk about popular American culture being out of touch with traditional American life — the kind of life/lifestyle they think most Republican voters want. That’s a new spin on the culture wars, but it’s also given the GOP candidates ways to talk about being manly men and to have that characterization make them stand in opposition to what they might see as an increasingly “effeminate” culture — talking about sexism, homophobia, etc., in our everyday lives.

In August, Jennifer Jones, a PhD candidate in the department of political science at the University of California at Irvine, detailed in The Post how Clinton's speech has become more “masculine” in the past two decades of her political career.

It compared “feminine” and “masculine” words Clinton used in public statements in 1996 and 2014.

“In 1996, Clinton said “I” eight times and “we” only once, indicating a more personal, feminine style. In 2014, however, Clinton did not say “I” even once, but said “we” or “our” three times.

“Her 2014 response is less tentative and self-conscious, but more complex and distant — all markers of masculine language.”

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