Humans have debated things large and small over the millennia, from democracy to breastfeeding in public to how often people ought to wash their sheets. But perhaps the most silly-yet-surprisingly heated household debate is the one in which we argue over which way to hang the toilet paper roll.

The “over or under” question has plagued marriages and casual acquaintances alike for over 100 years, with both sides convinced they have the soundest reasoning for putting their toilet paper loose end out or loose end under. Some people feel so strongly about right vs. wrong TP hanging that they will even flip the roll over when they go to the bathroom in the homes of strangers.

Contrary to popular belief, it’s not merely an inconsequential preference. According to health experts and the man who invented the toilet paper roll, there is actually a “correct” way to hang toilet paper.

What is the correct way to hang a roll of toilet paper?

First, let’s be clear about what we’re even talking about here with a visual. In the image below, left is “over” and right is “under.”

So which one is the right way? According to health experts, “over” is the way to........

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