Scientists at Tokyo Women's Medical University are claiming that using a mobile phone does not increase your chances of brain cancer.
The research is the first to look at the effects of radiation on different parts of the brains, says Reuters.
The Japanese team compared mobile phone use in 322 brain cancer patients with 683 healthy people and found that regularly using a mobile did not significantly affect the likelihood of getting brain cancer.
The project also studied the radiation emitted from different types of phones to assess the impact on different areas of the brain.
Naohito Yamaguchi, the scientist who led the research said: "Using our newly developed and more accurate techniques, we found no association between mobile phone use and cancer, providing more evidence to suggest they don't cause brain cancer".
The team's findings have now been published in the British Journal of Cancer, and add to a growing number of reports that suggest mobile phone use is completely safe.
Reuters reports: "Despite an explosion in mobile phone use around the world since the 1980s, the number of cases of brain cancer has hardly changed".
However, Cancer Research UK urged some caution: "So far, studies have shown no evidence that mobile use is harmful, but we can't be completely sure about their long-term effects. Research is still ongoing", Lesley Walker, Cancer Research UK's director of cancer information told Reuters.