The number of cycling injuries among adults in the U.S. rose by about 6,500 each year between 1997 and 2013, and the medical costs associated with those injuries increased 137 percent, according to a new study published in the journal Injury Prevention.

The rise in injuries is due in part to the increasing popularity of cycling in the U.S., the research concludes. The study was conducted by scientists at the University of California at San Francisco, the Pacific Institute for Research and Evaluation in Maryland, and Curtin University in Australia.

The authors also suggest that the growing costs associated with these cycling injuries could be due to the climbing rate of severe injuries, including those that occur from collisions with cars, as well as an increase in injuries among older riders, who might need more time and care to recover.

Head Injuries Are the Biggest Problem

The majority of serious injuries from cycling have one thing in common, says Fred Rivara, M.D., M.P.H., a professor of pediatrics at the University of Washington. “Two thirds of hospitalizations and three quarters of deaths from bicycle injuries are due to head injuries,” he says. “The most effective way to prevent that from occurring is to wear a helmet.”

Indeed, extensive research has demonstrated that a helmet is the best way riders can protect themselves against head injuries—especially those that are potentially fatal.

We list some of our top-rated helmets below and offer advice on choosing a model that’s right for you.

The study authors note that fatal bike accidents in younger riders have decreased, possibly as a result of increased helmet use among children and teens. Cyclists older than 55, meanwhile, are twice as likely as younger riders to die in a collision with a car—“an indication that this is a more vulnerable population,” the authors note. And the risk of bleeding in the brain and other severe complications from head injuries after bicycle crashes increases with age.

Bike helmets are also an easy, relatively inexpensive mode of protection against injuries, explains Ted Miller, Ph.D., a principal research scientist at the Pacific Institute for Research and Evaluation in Maryland and a co-author of the new study.

“Helmets offer an excellent return on the investment,” he says. “Limbs heal a lot better than heads do.”

Here’s how to use Consumer Reports’ bicycle helmet ratings to pick a helmet that will provide the best level of protection for you and your family:

Choosing a Bike Helmet

Consumer Reports’ latest bicycle helmet ratings include 16 recommended adult helmets, including the Scott Arx Plus, $125, the Bell Muni, $65, and the Bell Draft, $40. Our top-rated helmet for kids is the Bontrager Solstice Youth, $40.

If you sometimes ride without a helmet because you find wearing one uncomfortable, Peter Anzalone, Consumer Reports’ senior test project leader for bike helmets, has three suggestions:

1. Get a snug fit. “A helmet that fits shouldn’t be uncomfortable,” Anzalone says. Try on a few in the store, and make sure to adjust the straps carefully. The helmet shouldn’t move much when you pull it forward, back, or side to side. (Learn how to get the right bike helmet fit.)

2. Choose a helmet with good ventilation. Wearing a helmet that lets some air in can make a big difference in your comfort, especially on a hot summer day. Our six top-rated helmets all have at least Very Good ventilation.

3. Check the weight. There is not huge variability in helmet weight, Anzalone says, but for people racking up lots of miles, choosing a lighter helmet can make a difference. Our top pick, the Scott Arx Plus, weighs just 270 grams, or about 9.5 ounces; the 6D ATB-1T weighs 500 grams. The specs on the model page for each helmet include its weight in grams (28.3 grams per ounce).

Whichever helmet you choose, pick one you like to wear so that you wear it all the time, not just some of the time.

“The bottom line is that you can’t foresee the future,” Anzalone says. “You wear a helmet for something you hope will never happen—but if it does, you’ll be happy you had it on.”

A helmet can be the difference between walking away “with your crumpled bicycle,” Miller says, and suffering an injury with lifelong consequences.

“We don’t really know how to reverse the damage done to the brain after a head injury,” says Rivara, who has seen that damage firsthand in the trauma center. “The only truly effective way to treat it is to prevent it from happening in the first place.”

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