Q: In recent Ask Mother Nature columns, I’ve noticed you guys have been tackling oddball “mysteries of the human body” type of questions like “why do I hiccup?” and “why does my stomach growl?” Good stuff. And now it’s my turn: What exactly is the deal with bellybutton lint? For as long as I can remember, my navel (I’m a true “innie”) has acted as a fluff magnet. It’s not burdensome or anything but slightly odd since I’ve asked a few peers both male and female about their experiences with bellybutton lint and, well, they don’t seem as extreme. So why me? And how can I minimize navel fluff accumulation without having to join a nudist colony?


Pablo, Austin, Texas


Hey Pablo,

I realize I don’t know you or anything but I have to ask: Are you "male, older, hairy, and have an innie"?

If this is the case, you aren’t alone. Or at least according to University of Sidney researcher and author Karl Kruszelnicki and his earth-shattering, mock Nobel Prize-winning bellybutton lint study. After enlisting nearly 5,000 people to participate in the study (can you imagine him trying to recruit volunteers?), Kruszelnicki found that the above demographic was the most prone to generating bellybutton lint or BBL. Does the above description not sound like you, Pablo? Well, I don’t know what to tell you. 

But in all seriousness, Kruszelnicki wasn’t the only intrepid BBL researcher to find that hair growing around the navel and farther down south played an integral part in BBL generation. As reported by The Telegraph, in 2009 an Austrian chemist named Georg Steinhauser further examined the exact correlation between belly hair and BBL. After examining 503 pieces of BBL originating from his own navel, Steinhauser concluded that belly hair “often seems to grow in concentric circles around the navel” and have scales “that act like barbed hooks.” Through close contact with clothing, these hooklike hairs collect tiny pieces of fiber and guide it toward the moist bellybutton where it builds up. And voila! BBL is born. But wait … BBL isn’t just lint. According to chemical tests run by Steinhauser, that fluff is also composed of dead skin, sweat, dust and fat.

Want to partake in a science experiment/body grooming project? Steinhauser recommends shaving your abdomen to see what happens before the hair grows back. Will your navel continue to act like a drying machine lint trap? Or will it remain fluff-free? Also, if you’re just dying to take up body ornamentation as a hobby, now’s your chance since installing a BBL shield (AKA a bellybutton ring) is said to help keep fluff at bay. Not into shaving/waxing/piercing? Try wearing older clothing for a bit to see if that makes a difference. Apparently, new clothes shed more lint and can lose up to one thousandth of their weight to the navel in just a year. Learn something new every day, eh?

I wish I could recommend creative, crafty ways to repurpose BBL but it seems that Etsy seller Rachel Case has the bellybutton lint teddy bear market cornered. No doubt you could collect and compost it since dryer lint is compostable. But I’m not sure if I’ve ever heard of anyone actually doing this. Regardless, collecting the fluff in jars could prove to be a super effective way to repel unwanted visitors. Has your lonely, chatty neighbor outstayed her welcome? Just ask, “Hey, have I shown you my bellybutton lint collection yet?” and I guarantee she won’t be back to “borrow” a couple of eggs any time soon.

On the topic of collecting one’s BBL, I should alert you to a Mr. Graham Barker from Australia (what is it with bellybutton lint and Australians?). The 45-year-old librarian and “inquisitive collector” has been hoarding his own BBL for the last 26 years, amassing .77 ounces of the stuff. Remarks Barker on his blog: “I've been collecting my navel fluff consistently for around 20 years and have seldom missed a day's harvest. This makes my collection almost complete, a bit like having the full set of a country's currency.”

Barker, who also collects beard clippings and ski passes among other things, refers to bellybutton lint as "that fascinating fluffy substance that forms mysteriously in the belly buttons of special people." So look at it that way, Pablo. You're not a navel-lint generating freak of nature. You're special.

— Matt

Also on MNN: Don't miss this infographic: 28 odd facts about the human body

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Photo: trait2lumiere/iStockphoto

Matt Hickman ( @mattyhick ) writes about design, architecture and the intersection between the natural world and the built environment.

What's the deal with bellybutton lint?
It's time for some navel gazing with a couple of scientists and a collector.