Cell phones do not give you brain cancer

A second case-control study — run in multiple countries — found no effect overall but an increase in tumor rates for those individuals who used their phones most; that is, the top 10 percent of users. The authors of the study were cautious in interpreting their results, but it remains concerning that heavy use would matter.

However, these links are not seen in the two large prospective studies on this issue. One, a Danish cohort study, followed effectively all individuals in Denmark (again, such a large sample is really the only way to detect effects) and used administrative data (from the phone company) on their mobile phone subscriptions. This study found no effect on brain tumors of any type.

A study of almost 1 million women in the U.K. came to the same conclusions. This one asked women about their phone use and then followed them for seven years. Researchers found no link with most cancers. There was a weak link between heavy cellphone use and a cancer called acoustic neuroma, although the authors effectively concluded that this link was a spurious correlation in the data.