In the informative Coursera MOOC on social marketing that I’m presently taking, a number of stats were thrown at us. My favorite: “More people own a mobile device than a toothbrush.”

If you’ve been reading my blog, you know that I’m not going to accept this kind of statement at face value (see previous blog, Or Would You Rather Be a Fish?). So I had to dig deeper to find out if it’s true.

60 Second Marketer Nicole Hall traced the origins and accuracy of this statistic in 2011. She looked at statistics on subscriptions to cell phone services and deduced the number of mobile phones owned worldwide.

Then Hall unpacked the statistic from Oral-B that yearly global toothbrush sales were about $5 billion. She concluded that, yes, “more people own a mobile phone on the planet than own a toothbrush.”

Jumping on this conclusion, I was all ready to discuss the oral hygiene of mobile phone users without toothbushes—poor oral hygiene leads to rotting teeth, leads to less romantic relationships, leads to less sex and less children. Could mobile phones be a new form of birth control? (Is that so much more far-fetched than many of the dire predictions people are making about the impact of mobile phones?)

But, my friend Lindsay reminded me that not everyone uses a plastic toothbrush to ward off tooth decay. As a Peace Corps volunteer in Ethiopia, she observed Ethiopians using roots or twigs to clean their teeth. Apparently, I was thinking about this in a culturally biased way. Shame on me.

So I had to find out how the rest of the world takes care of their oral health. Not only do Ethiopians and their West African neighbors brush with and chew twigs to clean their teeth and freshen their breath, but according to researchers these twigs are very effective at fighting bacteria.

Protection from gum disease and other ailments is associated with the use of chewing sticks from the Neem tree in India and twigs called Miswaks that have been used by Muslims for centuries. (You can buy Neem toothpaste and Miswaks on Amazon.) In other words, most people in the world are brushing their teeth.

Now that data is part of our everyday lives and shaping our lives online, we need to be very careful about how we interpret it. Comparing unrelated variables is particularly tricky. Despite Hall’s excellent research, the statement should be: More people own a mobile device than a Western style toothbrush. Putting it that way makes it less intriguing and even more trivial.

For those of you who are thinking about how mobile phones are changing our lives and the potential impact of social marketing, here are a couple of examples of more relevant comparison data:

More than 50% of US adults aged 18-44 have cellphones rather than telephone landlines in their homes.

Americans now spend more time accessing digital media on mobile devices than they do on desktop or laptop computers.

Now these stats are worth thinking about next time you brush your teeth.