However, the company's decision has come under strong criticism from users and a number of countries, including South Korea and France.
On Tuesday, France demanded that the internet giant postpone rolling out the policy due to come into effect on Thursday, as it appeared to break European Union data protection rules.
In January, the European Commission launched a bid to make companies, including internet giants such as Google or Facebook, give people more control over their personal data or face big fines.
The proposal, championed by Viviane Reding, the EU justice commissioner, would force all companies to get explicit consent from customers to collect their data, explain how it will be used, and allow users to completely erase their information.
Google, however, has defended its decision in a blog post. The company says the changes are designed to improve the user experience across various Google products, which range from web search to Gmail, YouTube and Google+, the social networking platform launched by the company last year.
The main change involves users who have Google accounts.
"If you're signed in, we may combine information you've provided from one service with information from other services," Whitten said. "In short, we'll treat you as a single user across all our products, which will mean a simpler, more intuitive Google experience."
'Can't violate US law'
Eric Schmidt, Google's executive chairman, on Tuesday, indirectly addressed the issue during a keynote speech at the Mobile World Congress, the world's biggest mobile technology fair, in Barcelona.
Schmidt urged regulators to allow technology to develop its own solutions, saying that drawing up specific laws could stifle innovation.
He told the gathering that "pro-democracy, pro-communication, pro-freedom of expression bias" were "one of the best exports out of our industry" but then told the gathering that the company was still subject to countries' laws.
Referring to Google's block on Android or Chrome downloads in Iran, Schmidt said that the ban was due to US sanctions on Iran and that "we can't violate US law".
Schmidt also pointed to Europe's "strong commitment to privacy" but said that "if you look at recent initiatives, they are well intentioned but harder to define".
While he noted the role that the internet had played in the Arab Spring, he said that "decisions that are being made by technology companies are in fact quite consequential".
"The fact that information is hard to block has implications for the Arab Spring. So there's a lot of reasons that have a political consequence, they don't have a political goal but a political consequence," he said.