Spending 50 minutes with a cellphone plastered to your ear is enough to change brain cell activity in the part of the brain closest to the antenna. But whether that causes any harm is not clear, according to scientists at the National Institutes of Health, who added that the study will likely not settle recurring concerns of a link between cellphones and brain cancer. Use of the devices has increased dramatically since they were introduced in the early-to-mid 1980s, with about 5 billion mobile phones now in use worldwide. Some studies have linked cellphone exposure to an increased risk of brain cancers, but a large study by the World Health Organization was inconclusive. The team studied 47 people who had brain scans while a cellphone was turned on for 50 minutes and another while the phone was turned off. While there was no overall change in brain metabolism, they found a 7% increase in brain metabolism in the region closest to the cellphone antenna when the phone was on. The findings suggest the need for more study to see if cellphones have a negative effect on brain cells, the researcher say.
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