People wanting to lower their risk of developing cancer by taking aspirin need to take the over-the-counter medication "for at least five years", according to the scientist who established the link.
Professor Jack Cuzick told Good Morning Britain the five year timeframe was why it had taken researchers "so long to see" the health benefits.
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Two people were injured when a gun was fired during the French president's speech.
At least nine members of a school marching band were among the injured, according to local media.
Police investigating the disappearance of a British toddler in Germany more than 35 years ago have released an image of a suspect.