Vindication! Science confirms that the best way to cut a sandwich is into triangles.

Very clever mathematician, Caroline Delbert, over at Popular Mechanics has put those university degrees to good use and broken down exactly why the triangle method is superior to the rectangles.

The reason why triangles are the preferred technique for those who actually enjoy food is that you – in a roundabout sort of way – get more sandwich from your sandwich. As Delbert puts it, it’s basic geometry and the law of conservation of matter. Bear with us. 

In a rectangular sandwich half, there’s one perfect middle bite where the ratio of filling to bread is spot on. That bite is surrounded by three crust-heavy bits, plus two corner bites that have double crust corners. 

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When you’ve got a beautiful triangle sandwich half however, access to the sandwich filling is greatly increased while the ratio of crust to filling is diminished. The triangle shape allows access to one central excellent bite, a couple of good side-bites with a balanced ratio of crust, and just the one yucky double-crust bite corner. 

So the maths checks out – triangles are technically better than rectangles.

Delbert then measured the anecdotal evidence with a very official Instagram poll, positing the question of what the correct way to cut a sandwich is. The overwhelming majority of respondents opt for triangles.

It should be noted that all participants in the poll were adults. No matter how you cut a child’s sandwich, it’s wrong.

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However, there are different horses for different courses. For instance, some sandwich fillings require greater structural integrity than others. A heavier, or more moist sandwich filling like chicken salad, tuna, or roasted vegetables, fares far better with more support – in rectangles, we trust.

The cross-section close up of a rectangle is also hard to deny as the crust naturally frames the sandwich. Aesthetics, darling, aesthetics. Good luck trying to take a big bite of a rectangle without ending up with sauce on your cheeks though. Triangle takes the lead again.

A hot sandwich like a panini or a cheese toastie benefits greatly from the point to point triangle. Heat can escape more consistently from the centre of the triangle half, and the cheese is more evenly distributed toward the crusts.

So there you have it!

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