No big surprise: Bicyclists who wear helmets are less likely to suffer major head injuries than those who don’t.

A study by researchers at the University of Arizona showed that helmet-wearing cyclists enjoy 58 percent lower odds of severe traumatic brain injury.

The findings were presented today at the 2015 Clinical Congress of the American College of Surgeons. The authors say they hope the findings encourage helmet use, the development of better helmets, and the creation of stricter helmet laws.

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No Doubt Helmets Help

Researchers used data from the 2012 National Trauma Data Bank of the American College of Surgeons to analyze nearly 6,300 patients who had a traumatic brain injury after a bicycle-related accident.

Only about 25 percent of those cyclists were wearing helmets.

“We know for a fact that helmets help you prevent head bleeds in case you get into a bicycle-related accident,” Dr. Ansab Haider, a research fellow at the University of Arizona and one of the study’s authors, said in a press release. “But the real question was, if you get into a bicycle-related accident and end up with a head bleed, does helmet use somehow protect you?”

The answer is yes.

Not only do helmet-wearing riders have dramatically lower odds of severe traumatic brain injury, they are far less likely to end up dead in an accident.

“If you are severely injured and you were wearing a helmet, you are going to fare better than if you were not,” Dr. Bellal Joseph, an associate professor at the University of Arizona and the study’s lead author, said in a statement.

“It's pretty much common sense. People put themselves at risk when they don’t wear a helmet,” San Francisco Police spokesman Albie Esparza told Healthline. “We have seen people with helmets on that make a vast difference in injuries. We'd rather see that than the latter — death from a collision.”

But not all cyclists are enthusiastic about helmet laws, which some bike advocacy groups call paternalistic and a violation of personal freedom of choice. “I don’t want our work to be interpreted as being opposed to wearing helmets,” said Dave Snyder, executive director of the California Bicycle Coalition, in a news release earlier this year. “Of course racers and sport riders should wear helmets, and anyone who wants to wear a helmet should be supported in that choice.”

In San Francisco, where local officials are considering new cycling laws that would allow people on bikes to roll through some stop signs and signals without stopping, the helmet law controversy has been raging for two decades.

The San Francisco Bicycle Coalition declined to comment on this story.

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Who Wears a Helmet and Who Doesn’t

Researchers also delved into what relationship age and gender had on bicycle accidents resulting in traumatic brain injury.

“The lowest incidence of helmet use was seen in the age group of 10 to 20 years. But as we went up every 10 years, the likelihood of helmet use went up,” Haider said.

The study also found that females are more likely to wear helmets than males.

“A lot of people wear helmets on their own already. It’s great to see that,” Esparza said. “It's all about safety. You want to make sure you protect yourself when you're out there riding.”

“Ultimately, the important message is patient care and how we can make our patients safer and more protected,” Joseph said. “We need to take this data and take it to the next level and move forward with policy and injury prevention, especially for the younger age groups.”

But that’s easier said than done.

“We enforce the law,” Esparza said. “It’s up to the legislators to come up with stricter laws.”

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