If you’re riding your bike in the suburbs of Washington, D.C., with your head unprotected, don’t be surprised if you hear a voice bellowing at you from a passing car: “Get a helmet!” It could be Consumer Product Safety Commission Chairman Elliot Kaye’s 6-year-old son, who has taken it upon himself to be a sometime cycling safety advocate. “I applaud him loudly for it,” Kaye laughs. “Once we’re out of earshot.”

Both generations of the Kaye family understand an often overlooked reality: Head injuries are a serious problem in cycling. For all of the news about traumatic brain injuries (TBIs) among football players, there were 286,978 bike-related head injuries treated in U.S. emergency rooms between 2007 and 2011—more than from any other sport—according to a 2016 study published in BMC Emergency Medicine. Consumer Reports ratings can help you find the best bike helmet for you.

Find the Best Bike Helmet

According to a study by the Insurance Institute for Highway Safety, 60 percent of people who died in a bike accident in 2014 were not wearing a helmet. Almost half of the 1,189 cycling accidents in people ages 5 to 18 in one Minnesota county involved a head injury, according to a study by Ruchi Kaushik and colleagues at the Mayo Clinic Children’s Center. Of the 11 kids who were hurt the worst, including two deaths, 10 of them were helmetless. And a helmet can mean the difference between injury and disaster. When researchers at the University of Arizona in Tucson analyzed the records of more than 6,200 people nationwide who had a TBI as the result of a bike accident, they found that wearing a helmet cuts the risk of severe injury by 58 percent.

Bike Helmets and Concussions

Those numbers should be convincing enough to erase any doubt about the benefits of helmets. Still, no one knows whether or by how much they reduce concussion risk. “You wear a helmet to protect yourself from head injuries that can kill you,” says Robert Cantu, M.D., Clinical Professor of Neurology and Neuro­surgery at Boston University Medical School. Those include skull fractures and bleeding inside the skull or the brain. Scientists know how much force it takes to crack a skull, so they’ve been able to design a test that determines a helmet’s ability to prevent that. But concussions aren’t completely understood, and not all TBIs are perceivable on a CT scan or an MRI, which makes devising a test to measure the force it takes to cause one difficult.  

However, it seems likely that helmets help somewhat because in a crash the materials they are made of blunt impact and disperse energy; that may keep the brain from jostling too much inside the skull, which is the cause of concussions.


An Extra Layer of Protection?

After going for decades with few safety-related changes, helmet manufacturers are beginning to innovate with concussion prevention in mind. Questions remain, but our tests this year suggest that, at least in the lab, there may be some added benefit to a technology called Multi-­directional Impact Protection System, or MIPS, which is increasingly being used in bike helmets. 

Bike helmets are currently tested for their ability to protect against severe head injury. But MIPS is a thin, low-friction liner inside the helmet allows the outer shell to slide a few millimeters across the skull on impact, reducing rotational force and the amount of energy transferred to the head. That may help reduce the chances of suffering a concussion.

In addition to our standard tests, we compared the rotational impact performance of MIPS and non-MIPS versions of two helmets, the Bell Draft and Specialized Chamonix. The MIPS helmets reduced rotational force up to 43 percent compared with the same brand’s non-MIPS version.

There’s enough science to say that rotational force is a prime factor in concussion, but the Consumer Product Safety Commission warns against assuming too strong a connection between a helmet’s ability to absorb energy in a lab test and its ability to prevent a concussion in a real-world crash.

“What impact threshold would trigger a concussion?” says Consumer Product Safety Commission chairman Kaye. “I think we could adopt a test method to better collect information, but we can’t definitively correlate what that information means in terms of injury prevention or risk reduction.”

That said, both versions of the Bell Draft are recommended in our Ratings. The MIPS helmets in our comparison are priced at $20 to $25 more than the non-MIPS versions. Even if the extra benefit isn’t definitive, a MIPS helmet might be worth the extra cost. 

No helmet offers complete protection in every accident. But helmets are comfortable, you don’t have to spend a lot of money to get a good one, and it could save your life. That’s why you should wear a bike helmet every time you ride—or risk getting heckled by a precocious 6-year-old.

Editor's Note: This article also appeared in the August 2016 issue of Consumer Reports magazine.