You can try this one at home, if you want, but it’s going to turn out badly for you. — Dan

Dental care is an important part of maintaining your health. So hopefully, brushing your teeth is part of your morning and evening routines. The American Dental Association makes that clear, recommending that you “brush your teeth twice a day with a fluoride toothpaste for two minutes.” It’s easy and typically has no meaningful downside — unless your morning routine also includes a breakfast that includes orange juice. Because as anyone who has ever sipped that morning OJ too soon after brushing their teeth knows, that’s a terrible idea — the OJ tastes awful.

Blame the science of brushing.

Toothpaste is an emulsion — a mixture of two liquids that typically don’t mix. It’s designed that way to make it easy to transport and use. The gel sits in a tube until we squeeze it onto our toothbrushes, and then it waits until we start brushing. Unless you squeeze too hard or are bad at getting the cap off the tube, there’s no mess.

But when you start brushing, the toothpaste begins to transform into a foamy mess. That’s also by design. Toothpaste contains a cleansing agent — that’s the whole point — but for the cleansing agent to do its job, it needs to come in contact with your teeth. Once the toothpaste is in your mouth, you want it to move all around, cleaning your teeth as much as possible. The foaming ingredient, sodium lauryl sulfate (SLS), takes care of that part of the job.

For fans of OJ, though, SLS comes with a downside. First, it screws with our tastebuds. As the BBC explains, SLS temporarily “suppresses sweet receptors on the tongue, which prevents the brain from registering sweetness.” Like a piece of gum that you’ve chewed for way, way too long, your mouth doesn’t notice anything tasty about the experience — the textures are the same, but the flavors are gone.

And then, it gets worse. SLS helps protect our teeth by breaking down fats called phospholipids. But as Colgate explains, phospholipids often help reduce the bitter tastes found in our foods by blocking those taste receptors. Without those fats present in our mouths, the bitterness of the OJ shines through. Less sweetness plus more bitterness? That’s a flavor disaster.

The good news is that this is easy to solve. You should eat an hour before you brush anyway — it’s better for your teeth — and if you do, the OJ is probably gone before the SLS can wreak its havoc. Or, if you really want to brush your teeth more often, you can find toothpastes without SLS or other foaming agents.

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Today’s Bonus fact: Another reason you should drink your OJ, wait a while, and then brush: you actually may be harming your teeth if you don’t wait. Per the Mayo Clinic, “to protect your teeth, don't brush them right after having food or drinks that contain a lot of acids. Examples include soft drinks, such as soda and sports drinks, sour candies, citrus juices [like, OJ] and citrus fruits. The acid in them can soften the enamel. Brushing too soon after you eat or drink something acidic can take the enamel off your teeth.” So wait an hour — or just drink the OJ with lunch.

From the Archives: The Minty-Fresh Way to Fail At Business: Toothpaste-flavored foods?

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And thanks! — Dan