Do cell phones cause cancer?

When talking on your cell phone, it may be best to use a speaker or a hands-free device. Science has not definitively answered the question of whether cell phone use can lead to brain cancer, but it is always wise to take steps to prevent cancer.

Most studies dating back to the late 1990s have shown no relationship between cell phone use and brain cancer, but some suggest a cause-and-effect relationship. A recent Swedish study found that prolonged use of cell phones can increase a person’s risk of developing glioma, adding to a growing body of research aimed at solving the problem.

Why are cell phones a concern? Cell phones emit radio frequency energy that is absorbed by the body tissues closest to the phone. Radio frequency energy from cell phones, microwave ovens, and radar is a non-ionizing form of electromagnetic radiation. On the other hand, X-rays and radon are ionizing radiation, which have been shown to increase the risk of cancer.

The widespread use of cell phones, with more than 300 million subscribers in the United States in 2010, has drawn more attention to the potential health effects of repeatedly holding a phone on the ear. The latest Swedish study, published in Pathophysiology in October, compared cellular and cordless phone use of 1,380 people with malignant brain tumors with the same number of people without them.

Swedes who spoke for more than 1,486 hours, which equates to about two months, were twice as likely to develop gliomas as those who spoke for less than 122 hours, or about five days. The risk of brain cancer tripled among Swedes who used cell phones or cordless phones for more than 25 years and doubled among those who used these phones between the ages of 20 and 25. The researchers included cell phones in their study due to concerns about emissions from phone base stations.

The study relied on its participants to accurately remember their previous phone use, which could be considered a deficit. Study participants with brain tumors may have inadvertently amplified responses because they wanted to identify the cause of the cancer.

The Swedish study is a case-control study, which means it compared cell phone use for those with tumors and those who did not. It’s the same study design as the Interphone Study, which is the largest case-control study looking at cell phone use and cancer. With researchers from 13 countries and published in 2010, the study found no statistically significant increase in brain or central nervous system cancers.

Note that your individual exposure to RF energy from your cell phone varies with the amount of time you spend on the phone, the model of your phone, whether you’re using a speaker or a hands-free device, the distance, the route to the nearest cell phone tower, and the amount of cell phone traffic at that time.

To reduce your exposure, keep phone conversations brief. Use a hands-free device or speaker. And text instead of talking, when it’s safe to do so.

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