By Darren Waters
Technology editor, BBC News
Users benefit when Google can keep data, said Larry Page.
Forcing Google to delete user data after six months could dent its ability to predict pandemics such as swine flu, said the search giant's co-founder.
Larry Page said he thought more debate was needed around the issue of storing user data.
The European Commission wants data ditched after six months but Mr Page said there were benefits to users.
"More dialogue is needed [with regulators]," he told UK journalists at a Google event in Hertfordshire.
He said Google's ability to plot and predict potential pandemics would not be possible if the firm had to delete search data after six months.
"When we released data about Mexico flu trends we had a whole debate," he said.
"We were worried we would cause panic. But we decided the benefits outweighed the cost."
Mr Page said deleting search data after six months was "in direct conflict" with being able to map pandemics.
In a demo to journalists, Google showed that it had been able to spot a potential pandemic ahead of government agencies because it was using search data.
On its website about spotting flu trends, the firm says: "Our up-to-date influenza estimates may enable public health officials and health professionals to better respond to seasonal epidemics and pandemics."
Mr Page said the less data companies like Google were able to hold the "more likely we all are to die".
The European Commission has argued that holding on to search data runs the risk of third parties being able to build profiles of individuals even when some identifying information is deleted.
In September 2008, Google said it would anonymise data after nine months following pressure from Europe on the issue. Previously it had kept data, including IP addresses and search terms, for 18 months.
European advisers recommend that search engines should not keep data for more than six months.
Previously, Google argued that it had to keep data for longer to comply with requests for help from law enforcement agencies.