McDonald's Fries Might Make a Mouse Furrier, But They Probably Won't Cure Your Baldness

We will never again eat McDonald's fries without thinking about patchy-ass mice.
Photo via Flickr user Natasha C Dunn

The endearing English soccer broadcasters Men in Blazers recently started using the term BILF to describe one particularly handsome Spanish coach, because he’s bald and… yeah, you can figure out the back half of that acronym. If you’re proudly bald and want to maintain your own BILF status, you may have recently caught wind that McDonald’s fries could be a one-way ticket to Hairland. And we’re sorry to tell you, but it’s more complicated than that.


According to researchers at Japan’s Yokohama National University, there is a pretty interesting chemical, at least as far as hair loss goes, in McDonald’s French fries. That much is true.

Basically, Professor Junji Fukuda and his team have been working to find a way to reverse hair loss, which requires the large-scale reproduction of hair follicle germs (HPGs), which Fukuda defines as “the reproductive source of hair follicles.” In a paper published in the journal Biomechanics, the team wrote about their recent success in preparing 5,000 HPGs, transplanting them onto the scalp and back of a mouse, and discovering that black hair soon grew at a level that will make it embarrassing for the mouse to visit a public pool. The key, Fukuda said, was the choice of substrate that was used to transfer the HPGs to the mouse and, for this experiment, he used oxygen-permeable dimethylpolysiloxane. (“It worked very well,” he beamed).

If you spend your free time reading the fine print on McDonald’s website, dimethylpolysiloxane will sound familiar. It’s a type of silicone that is used in caulks, adhesive, breast implants—and , yes, in the fast food chain’s rather delicious fries. “Our fried menu items are cooked in a vegetable oil blend with citric acid added as a processing aid and dimethylpolysiloxane to reduce oil splatter when cooking,” the company writes on its website. And, although it’s easy to pick on McDonald’s, it’s not the only fast food joint adding dimethylpolysiloxane to its food.

Dimethylpolysiloxane (DMPS) is also used as an “anti-foam agent” in Chick-fil-A chicken sandwiches; in the fountain version of your favorite soda; in Wendy’s fries; in the oil that Five Guys and Jack in the Box fry their food in; in KFC’s mashed potatoes; in Whataburger’s namesake burger, egg sandwiches, and taquitos; and in Hardee’s chicken sandwiches, tenders and crispy curls—and this is by no means an exhaustive list.

Fukuda was pleased with DMPS’ performance as a substrate material, allowing his team to successfully transfer the HPGs to the mouse—and some hair loss bloggers are hopeful that he’s right about its potential in humans as well. “This simple method is very robust and promising,” he said. “We hope that this technique will improve human hair regenerative therapy to treat hair loss such as androgenic alopecia.”

But we’ll all have to stay tuned to see if DMPS will be used in further research into hair regeneration and, depending on your BILF status, you may or may not be delighted. Regardless of your BILF status, you’ll be thinking about a mouse’s artificially hairy back the next time you order those fries. You’re welcome.