Few things attract nasty germs like a kitchen sponge. Think about it. What else is used to clean dishes, wipe tables (and let’s be frank, sometimes the floor), food spills, mop up meat or vegetable fluid, grubby hands and dirty faces before it’s left to fester at the bottom of the kitchen sink in a puddle of lukewarm water.

The more diligent among us might throw our sponges in a bucket of hot water, bleach, in the microwave or even put it through the washing machine, but our efforts may all be in vain. New research that studied 14 household sponges has found that regularly sanitised sponges did not contain less bacteria than uncleaned ones.

“Sponge sanitation methods appear not sufficient to effectively reduce the bacterial load in kitchen sponges and might even increase the shares of [disease-linked] bacteria,” the authors wrote in the study. Which means that by trying to clean our kitchen sponges by zapping them in the microwave or boiling them we may actually be making them dirtier and more bacteria-ridden.

So what’s the solution? “We therefore rather suggest a regular (and easily affordable) replacement of kitchen sponges, for example, on a weekly basis,” wrote the authors.

It might not be good news for our hip pocket or the environment, but it’s definitely good news for our overall health.