So, let’s be honest: We don’t always wash our clothes as often as we should. Whether you use the classic “smell and evaluate” test, or prolong doing laundry as long as possible, you’re probably letting all the nasty stuff you acquire throughout your day accumulate on your favorite pair of jeans. But how often should you actually be washing your clothes? A new video by Brit Lab helps us figure out if it’s time to finally bite the bullet and go to the laundromat.

All human beings are pretty gross, if you truly think about it. We are constantly secreting strange substances, and shedding layers of skin; in fact, we shed up to 500 million skin cells, and secrete one liter of sweat each day. But on its own, sweat isn’t that smelly. It’s the bacteria living on your skin, which thrives by breaking down sweat and skin cells, that makes sweat the stench we’ve grown to revile. For example, Staphylococcus epidermidis bacteria, or the bacteria that lives on your skin, will break down amino acids in sweat and create a similar type of smell you’d find in stinky cheese.

But when it comes down to it, apocrine sweat is probably the worst brew we’ve got. Found near the genitals, breasts, under arms, and your eyelids, apocrine sweat glands mature at puberty and lead to the smelliest of smells. And guess where all of this is going? Your clothes.

Luckily, modern detergent is quite the smart invention, using surfactants that make stains water soluble, and easier to rinse away. But the question still remains: With all the stink and potential infections lying on our clothes, how often should we wash them away?

That seems to depend on the clothing item. Articles of clothing that are closer to those areas where apocrine sweat is active, like t-shirts, underwear, vests, and socks, should be washed each day. Towels, which also tend to grow bacteria because of their damp environments should be washed at most, three days after use. Pajamas too should be washed sooner than you think. A professor from the London School of Hygiene and Topical Medicine said you need to put those in the wash after a week of wear to prevent the possibility of infection.

But what about that pair of jeans you want to keep from fading? That seems to be up to you. If you care about style more than cleanliness, you may not wash your jeans for over a month’s time. But, if you’re into skinny jeans that hug most parts of you, it’s probably wise to wash those regularly.

To learn more, watch the video above.

Published by