Guardian Cap controversy reaches the NFL’s biggest stage

By Zoe Marquis. This article was initially published in the 2/5/26 Edition of our Concussion Update newsletter; please consider subscribing.

During this weekend’s Super Bowl, New England Patriots offensive lineman Jared Wilson will wear a Guardian Cap, a helmet cover designed to blunt head impacts. But conflicting claims by the NFL and Guardian Sports (the company that makes the Guardian Caps) bring the benefit of the caps into question, according to a recent article by Ken Belson for The New York Times.

 While the NFL claims that Guardian Caps reduce the risk of concussions, Erin Hanson, a co-founder of Guardian Sports, said the Guardian Cap “has nothing to do with concussions.” Rather, according to the company, the caps are meant to “blunt the impact of smaller hits to the head that are linked to long-term brain damage.” 

The controversy stems from a study that looked at the rate of concussions in preseason practices from 2018 to 2023. In 2021, the NFL required linemen, tight ends, and linebackers to wear Guardian Caps in training camp. In 2023, the NFL added running backs and fullbacks to the list and mandated caps for these positions in all contact practices. According to the researchers, including some affiliated with the N.F.L., concussion rates declined between 54 and 62 percent over that period. However, they cautioned against any conclusions attributing this reduction to the Guardian Caps alone. 

According to Belson, the researchers also noted that the relationship between concussions and the use of Guardian Caps lost statistical significance “when looking only at concussions caused by hits to the helmet shell — one of the most common causes of concussions.”Belson notes that a position paper from the National Athletic Trainers’ Association specifically states that “‘helmet add-on products may overstate injury prevention benefits.’”