Americans live far more dangerously than our European counterparts when it comes to texting and driving, with more than two-thirds of us admitting to texting while at the wheel, federal government researchers reported on Thursday.

A survey of drivers across the United States and Europe shows big differences in the numbers who admit they get distracted at the phone, but the U.S. scored by far the worst.

Just short of 69 percent of Americans aged 18 to 64 admitted to talking on a cell phone while driving at least once in the past 30 days. This compared to 21 percent of British drivers, who were the least likely to text and drive, and 40 percent of adults in France. And 31 percent of U.S. drivers admitted they had texted at the wheel, compared to 15 percent in Spain.

What puzzles the researchers is why the numbers are so different across the seven European countries in the survey: Belgium, Britain, France, Germany, the Netherlands, Portugal and Spain.

“While U.S. states differ in their cell phone use laws, nearly all European countries have hand-held bans in place, yet there is still a large variation in European estimates,” wrote Rebecca Naumann and Ann Dellinger of the National Center for Injury Prevention and Control.

Virtually all experts agree that talking on a cellphone or using one to write texts or emails is enormously distracting. Even hands-free use can be a major distraction and health experts say people shouldn’t use phones at all while driving.

A team at the University of North Texas Health Science Center reported in 2010 that drivers distracted by cell phones killed an estimated 16,000 people from 2001 to 2007, based on National Highway Traffic Safety Administration data.

Various U.S. states have tried making it a crime to use a handset while driving, communication campaigns, devices that discourage cellphone use in a moving vehicle and education. The CDC says 33 states and the District of Columbia have laws restricting at least some teens or new drivers from using cell phones while driving.

The National Transportation Safety Board has recommended a blanket ban on the use of cellphones in cars and also encourages the development of technology that would disable cellphone function within reach of a driver in a moving vehicle.

“The cell phone can be a fatal distraction for those who use it while they drive,” CDC Director Dr. Tom Frieden said in a statement.  “Driving and dialing or texting don’t mix. If you are driving, pull over to a safe place and stop before you use your cell phone.”

Linda Degutis, director of CDC’s National Center for Injury Prevention and Control, says parents should model safe driving behavior. “It’s especially risky for young, inexperienced  drivers -- who are already extremely vulnerable to crashes -- to be distracted when they are behind the wheel. Answering a call or reading a text is never worth a loss of life,” she said.

The CDC team used data from 5,000 people surveyed by marketing and public relations firm Porter Novelli for the study.

Related links:

• California legalizes hands-free texting while driving
• Texting while driving like Russian roulette
• Why cellphone using drivers won't quit
• Texting pedestrians asking for trouble

Tim Mosenfelder / Getty Images Contributor

Sheryl Crow performs at the Mountain Winery on July 22, 2012 in Saratoga, Calif.

Singer Sheryl Crow says she believes her benign brain tumor was caused by frequent cellphone use, but the science to date does not support her theory.

Crow said that although no doctors will confirm it, she thinks it's possible her brain tumor, called a meningioma, is related to her cellphone use. "I [used to spend] hours on the old, archaic cellphones," Crow said on Monday's episode of Katie Couric's daytime talk show "Katie."

However, there is little evidence linking cellphone use to brain tumors, and most studies have not found a link. For one thing, brain tumors aren't any more common, although cellphone use has exploded.

"There is no conclusive proof that cellphones cause brain tumors," said Dr. Michael Schulder, vice chairman of the department of neurosurgery at Cushing Neuroscience Institute in Manhasset, N.Y.

About 6,000 people are diagnosed with meningiomas yearly in the U.S., according to the National Cancer Institute. Schulder told MyHealthNewsDaily that Crow falls into the group that is most prone to developing meningiomas — women in their 40s and 50s.

Although they're called brain tumors, meningiomas actually form in the lining of the brain rather than the brain itself. Most are benign, meaning they are unlikely to spread to other sites within the body.

"There is no reason to think that there's some other extra cause" for Crow's meningioma. "She meets the risk factor profile for developing that tumor," said Schulder, who is not involved in Crow's care.

Cellphones emit radiofrequency energy, which can be absorbed by tissues, according to the NCI. But so far, the only known biological effect of this energy, which is also emitted by microwave ovens, is a tiny rise in temperature, the NCI says. Unlike the ionizing radiation in X-rays, radiofrequency energy is not known to damage DNA. (Damage to DNA is considered a necessary step to cause cancer, the NCI says.)

A Danish study of nearly 2.9 million people that was published last year found that those who used cellphones for 11 years or more were no more likely to develop a type of benign brain tumor called a vestibular schwannoma than those who used cellphones for a shorter period, or not at all.

Another 2011 study from Denmark found no link between the location of brain tumors called gliomas and the regions of the brain that are exposed to the highest levels of radiofrequency energy.

In addition, between the 1987 and 2007, a period when cellphone use rose rapidly, there was no increase in the incidence of brain cancer in the United States, the NCI says.

A U.S. government study published last year did find that people who used a cellphone for 50 minutes showed an increase in sugar metabolism in the tissues on the side of their head closest to the phone. However, the health outcomes of this increased metabolism were not known, the researchers said. In May 2011, the World Health Organization said it was conceivable that cellphones might cause cancer.

Because cellphone technology is changing rapidly, and people use cellphones differently from in the past, more research is needed on the possibility of a link between cellphones and cancer, the NCI says.

In the meantime, Schulder said, people can use hands-free devices, such as headsets, to avoid unnecessary exposure to cellphone radiofrequency energy.

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