Recently, I reached into a friend’s freezer for an ice sphere and came across a pair of neatly folded jeans. This sight took me by surprise not because it was unusual, but because the practice felt so dated. For those that might not have heard of the practice, the idea behind freezing your jeans is that freezing denim kills bacteria from well-worn jeans without actually having to wash them and affect the fade or overall integrity of the denim.
In reality, wear affects the fabric just as much, if not more than, regularly washing denim.
Though people have anecdotally frozen their denim for years, more as an odor-removing process than anything else, Levi Strauss actually pushed this practice into the mainstream in 2011. As part of a conservation effort, the company urged people to freeze their jeans to get more time between washes, but scientists agree that the process just makes most of those germs dormant.
Between washes, your best bet is to hang your denim outside or by a window or fan to diminish odors and bacteria.
“One might think that if the temperature drops well below the human body temperature [the bacteria] will not survive, but actually many will,” Stephen Craig Cary, a University of Delaware expert on frozen microbes told Smithsonian Magazine. “Many are preadapted to survive low temperatures.” (Don’t believe us? Read about this horrifying 30,000-year-old virus scientists were able to coax back to life after retrieving it in a soon-to-melt are of permafrost.)
Between washes, your best bet is to hang your denim outside or by a window or fan to diminish odors and bacteria, according to Rachel McQueen, a professor of human ecology at the University of Alberta in Canada. For a more aggressive attack on smells, fabric freshening sprays or diluted vinegar sprays should get the funk out.
Every four to six weeks, depending on wear frequency, you should wash your denim. Of course, they are your clothes, so you can go as long as you’re comfortable with, especially since most of the germs are just from your skin.
You can forget the bathtub method for all but very expensive raw denim; it’s time-consuming and won’t get your clothes as clean as a washing machine. Instead, isolate your denim in a cold wash where you should use anti-fade detergent or specially formulated denim detergent (like the recommended Heddels Denim Wash above). Turn everything inside out to protect the color and make it easier to get your body’s oils out of the fabric.
The actual worst culprit of detrimental denim washing is the dryer. You should never dry denim on high heat. A combination of medium to no heat and air drying (preferably just the latter, but sometimes you need your denim fast) will elongate the life of your threads and you don’t have to walk around in your own bacteria for months.