The chairwoman of the Food Standards Agency says workers should think twice before bringing unhealthy treats into the workplace and criticised delays to a television watershed for junk food advertising.
Bringing cake into the office is as harmful as passive smoking, the UK's top food watchdog has suggested.
Professor Susan Jebb, chairwoman of the Food Standards Agency, said workers should think twice before bringing unhealthy treats into the workplace which might tempt colleagues.
She told The Times: "We all like to think we're rational, intelligent, educated people who make informed choices the whole time, and we undervalue the impact of the environment.
"If nobody brought cakes into the office, I would not eat cakes in the day, but because people do bring cakes in, I eat them. Now, OK, I have made a choice, but people were making a choice to go into a smoky pub.
She added: "With smoking, after a very long time we have got to a place where we understand that individuals have to make some effort but that we can make their efforts more successful by having a supportive environment.
"We still don't feel like that about food."
Prof Jebb, a professor of diet and population health at the University of Oxford, said she was also frustrated by delays in introducing a television watershed for junk food advertising.
She said the advertisements are "undermining people's free will" and insisted restrictions were "not about the nanny state".
Prof Jebb added: "Advertising means that the businesses with the most money have the biggest influence on people's behaviour. That's not fair.
"At the moment we allow advertising for commercial gain with no health controls on it whatsoever and we've ended up with a complete market failure because what you get advertised is chocolate and not cauliflower."
A quarter of British adults are obese - a figure that has doubled in the past 30 years.
Steve Barclay, the health secretary, last month delayed plans set out by Boris Johnson when he was prime minister to end "buy one get one free" deals on unhealthy food and ban junk food advertising on television before 9pm.
Mr Barclay pushed implementation to 2025, which will be after the next election.