How to Stop Saying Um: The Real Reason You Use Filler Words (And How to Break the Habit)

If you've ever listened to a recording of yourself and cringed at how many times you said 'um' or 'you know,' you're not alone. Filler words are one of the most common verbal habits in the English-speaking world. They're also among the most misunderstood.

Why You Use Filler Words

Filler words are not a confidence problem. They're a symptom of cognitive load. When your brain is searching for the next word or idea — retrieving something from memory, selecting the right phrasing, deciding what to say next — it doesn't like silence. So it produces sound instead. 'Um' and 'uh' are place-holders that signal to your listener: I'm still here, I'm still thinking, I haven't finished.

Research on this is fairly settled. Linguists Herbert Clark and Jean Fox Tree analysed large corpora of spontaneous speech and found that 'uh' and 'um' aren't random noise — they're used systematically to announce an upcoming delay, a shorter one for 'uh' and a longer one for 'um,' often deliberately, to hold the floor while the speaker keeps thinking. They're not meaningless sounds. They're live negotiation with your listener. The problem is that in professional contexts — interviews, presentations, pitches — they erode perceived authority at a disproportionate rate.