Fully Known: Uh, do you know why you say um?

If your home church, like mine, featured a well-stocked book table, the title Men Are Like Waffles, Women Are Like Spaghetti might have caught your eye (The words “waffles” and “spaghetti” certainly arrested my attention). But I haven’t been able to come up with two foods that describe this bizarre difference between the genders: as a growing body of research indicates, men like to say “uh,” while women like to say “um.”

I call this a “bizarre difference” because I’ve always thought “um” and “uh” were perfect substitutes, kind of like Tweedledee and Tweedledum.

As it turns out, there are distinguishing characteristics between the two most common “language fillers,” differences that went long unnoticed even among linguistic experts. Then, in 2005, University of Pennsylvania linguist, Mark Liberman, found that men are twice as likely to say "uh" as women.

Eric K. Acton, a Stanford University PhD student, picked up the threat of Liberman’s research, publishing his findings on language fillers in 2011. I thought his technique was pretty sly—after three different speed-dating events, Acton analyzed the content of conversations between the graduate students in attendance, reviewing a total of 992 transcripts.

Acton concluded that “women’s average um/uh ratio is more than 3.5 times that of men.” He also noted that “while the so-called ‘fillers’ um and uh share a great deal in the way of interpretation, association and usage, they are far from perfect substitutes.” Unlike Tweedledee and Tweedledum, “um” and “uh” are fraternal twins.

Both language fillers signal a coming pause in the conversation, the speaker’s shorthand for gimme a sec. But in an email to Olga Khazan of The Atlantic, Liberman said, “people tend to use UM when they're trying to decide what to say, and UH when they're trying to decide how to say it."

It seems that, when engaged in conversation, men and women second-guess themselves for different reasons. “Women are more communicatively circumspect than men, and therefore more likely to pause before deciding what to say; but women are more linguistically fluent than men, and therefore less likely to pause while deciding what words to use,” Liberman suggested.

While you’re free to start noticing your speech patterns and making illuminating self-discoveries, this research is equally valuable for understanding the people around you.

If you’re one of those perfectionists who tries to avoid filler words then you probably don’t look kindly upon “sloppy speech” in others. Okay, I’m talking about myself. I spent six years competing in mock trial, which is basically a public speaking competition in a simulated court. Real attorneys judged most of the rounds. They handed back a paper wad with two hours' worth of their impatient scribbles.

And I really do appreciate the attorney who told me, in a single curt sentence, that adding “you know” at the end of sentences might be a misguided attempt at sounding conversational, but I sounded “tentative” and “weak." For the next few trials, I made sure I wrote “no you knows” on the inside of my wrist, and mentally hissed at myself to polish my sentences.

Here’s the thing about self-improvement: once you see progress, it’s easy to develop this snide inner voice that constantly criticizes those around you, even friends and family. And no one could call that self-improvement.

There is something commendable about the motive behind our “ums,” “likes” and “you knows.” Only people who care about the message they’re conveying will pause to consider their words. In support of this claim, a new study from The University Of Texas found that discourse markers such as “I mean” and “you know” correspond to a person’s empathy and conscientiousness—those traits create “a desire to share or rephrase opinions to recipients.”

Outside a competitive setting, displaying empathy really is more valuable than showing eloquence, I’d argue.

Actually, I’ll end with a tidbit of research you might enjoy. Nicholas Christenfeld, a University of California psychologist, published a paper in 1996 with the finding that drinking alcohol reduces “ums,” obviously not because of careful word choice, but because speakers care less about what they say.