“Cellphones don’t increase your risk of brain cancer, new study shows” – Miriam Stoppard

dr Miriam Stoppard discusses how fears over radio waves have sparked theories about cellphones causing brain tumors – but examining data from 776,000 people rules it out

Rumors of a link between cell phones and brain tumors have been circulating for years. The scaremongering has been reignited by the recent rollout of faster 5G technology.

Because cell phones are held close to the head, the radio frequency waves they emit penetrate the brain.

And since the International Agency for Research on Cancer (IARC) classifies radio waves as “possibly carcinogenic,” questions will naturally arise.

To date, most studies examining this question have been retrospective studies of people reporting cell phone use after being diagnosed with cancer, which means the results may be biased.

But Oxford researchers have conducted a prospective study – a study that enrolls participants before they develop cancer – to examine the possible link between cellphone use and brain tumor risk.

They used data from 776,000 participants in the UK Million Women Study, which includes one in four women born between 1935 and 1950.

They completed questionnaires about their cell phone use in 2001 and half were re-interviewed in 2011 and 2015. Cell phone use has been studied in relation to the risk of several types of brain tumors: glioma (a tumor of the nervous system); acoustic neuroma (tumor of the nerve connecting the brain and inner ear); meningioma (tumor of the membrane surrounding the brain); and pituitary tumors. The researchers also looked at whether mobile use is linked to the risk of eye tumors.

Their main findings were:

• Almost 75% of women aged 60-64 used a mobile phone, and almost 50% of women aged 75-79.
• 3,268 of the women developed a brain tumor, accounting for 0.42% of them.
• There were no significant differences in the risk of developing a brain tumor between people who had never used a cell phone and cell phone users.
• There was also no difference in the risk of developing glioma, acoustic neuroma, meningioma, pituitary or eye tumors.
• The incidence of right-sided and left-sided tumors was similar in cell phone users, although cell phone use tended to be significantly higher on the right side than on the left.

Fellow researcher Kirstin Pirie, from Oxford Population Health’s Cancer Epidemiology Unit, said: “These results support the growing evidence that cell phone use under normal conditions does not increase the risk of brain tumours.”

A tricky question remains. Would talking for a long time change the risk level? I don’t think so, because if you use your cell phone for longer chats, you’re more likely to use the hands-free function or the speakerphone.