Speaking to the BBC ahead of a speech regarding the National Health Service in Nottingham, he told reporters that he wanted to give the food industry a chance to prove it could regulate its own advertising, but warned the government would go further if it felt this was not working.
He said: "I would say my thinking has changed more towards intervention and away from simply letting things happen. In this policy area, the political debate has got to start meeting the public debate."
His comments come as the government moves to encourage the public to take some personal responsibility for their own personal well being to ease pressure on the NHS.
Blair said that successful campaigns like anti-smoking and the drive to make school dinners more healthy had changed his mind on the role, the state could play in improving the nation's health.
"What I do think you will see is the government intervening more directly -- and with the food and drink industry -- in circumstances, where for example, you have the sale of junk food to children and you have the irresponsible marketing of alcohol," he said.
Media regulator Ofcom is currently consulting on restricting junk food ads, but has already ruled out the option of a pre-9pm broadcast ban. The Institute of Practitioners in Advertising supports this, calling it "unjustified".
However, the Food Standards Agency says the three options set out so far by media watchdog Ofcom do not go far enough. It argues that banning ads for products like crisps and fizzy drinks would help protect children's health.
Pic: Crown Copyright
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