How A Dented Insulated Tumbler Can Ruin Your Cold Drinks

If you've tuned in to any Tik Tok trends over the past few years, you know that insulated tumblers are all the rage. From their thick handles, to their straws, to their array of pastel hues, these accessories create a fun, aesthetically-pleasing way to fulfill your daily water intake. But the advantages of insulated tumblers go beyond eye candy. Many brands claim to keep your liquid cold for a significant length of time — in the case of the Stanley Flowstate Tumbler that time is 11 hours for chilled drinks and 48 hours if ice is included — but if you're not careful, you can run into one fatal flaw that can ruin your tumbler's ability to do so.

If you find a deep dent in your bottle, it may no longer be able to keep your drinks cold. These accessories rely on a vacuum seal inside the tumbler, which maintains an internal temperature different from the one outside. Typically, these bottles feature double walls with the vacuum seal in between the two walls maintaining a barrier between your liquid and the outside world. If the dent is big enough that it forces both walls to touch, the integrity of this seal may be compromised, significantly lowering the amount of time your drink remains chilled.

The good news? Your insulated water bottle won't be ruined forever by any old dent. If you drop it onto something soft, like a couch or carpet, any resulting bump will likely be small enough that it won't bend the tumbler's double walls toward each other. In the same vein, scratches probably won't have an impact on the temperature of your beverage. But if you see larger craters that look like the shape of the metal has changed, you may want to test out your bottle's ability to keep your liquid cold.

You can prevent these larger bumps by treating your tumbler with care — meaning cushion it with softer items when in a backpack or tote bag, don't swing it around, and avoid dropping it if possible. If you want to go the extra mile, you can buy silicone boots that partially cover your tumbler, or sleeves that add protection and make it easier to grip. It's worth looking into these options if denting is a concern, because once your bottle is damaged, it's difficult to fix. There are methods you can try, including a few rounds of freezing water in your tumbler to pop out the dent through pressure, but they may not help if the dents are on the bottom. In that case, you're typically better off buying a new tumbler.