Ah, that sounds like a classic “life hack,” often touted as the ultimate insider tip! You’re probably referring to the problem of high humidity and musty smells in the bathroom.

The “rice cup trick” is essentially a homemade dehumidifier. Here’s the logic behind it—and a quick reality check:

How the trick works:

The cup: Fill the cup with dry, uncooked rice.

Extra: Often, a few drops of essential oil (e.g., lavender or eucalyptus) are added.

Effect: The rice is supposed to absorb the moisture from the air, while the oil subtly scents the bathroom.

Why it’s so popular (and where its limitations lie):

Bonus: It works wonderfully as a fragrance diffuser! Rice absorbs oil and releases fragrance more evenly than a simple air freshener. It also looks more decorative than a plastic air freshener.

Reality: As a dehumidifier, rice quickly reaches its limits. In a humid bathroom after a shower, you would actually need buckets full of rice to noticeably reduce the humidity. Rice is nowhere near as hygroscopic as, for example, professional silica gel or special dehumidifying salt.

My tip for the optimal solution:

If you use a jar of rice, it’s best to combine it with these two steps:

Ventilate thoroughly: Nothing is as effective as air exchange through a window (or a well-functioning range hood).

Salt instead of rice: If you really want to absorb moisture without electricity, coarse rock salt in a jar is often more effective than rice.

Let’s be honest: Do you primarily use rice to combat odors, or do you find that it actually reduces fogging on mirrors?

Shall I show you how to make an even stronger odor remover using baking soda and oil?