The official said that more needs to be done to promote healthy eating at work.
Professor Susan Jebb, chairwoman of the UK Food Standards Agency, has said that offices should rethink bringing cake into the workplace as it may pose the same harm to colleagues' health as passive smoking.
"We all like to think we're rational, intelligent, educated people who make informed choices all the time, and we undervalue the impact of the environment," she said.
"If nobody brought cakes into the office, I would not eat cakes during 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."
Speaking in a personal capacity and not on behalf of the FSA, she told The Times that the advertising of junk food is "undermining people's free will."
"Advertising means that the businesses with the most money have the biggest influence on people's behavior." 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," she added.
She pointed out that the effects of smoking and office cake consumption on health are completely different.
Ms. Jebb added that by making better eating choices, organisations can promote a "more successful" and "supportive" work atmosphere.
"With smoking, after a very long time, we have gotten 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," added Jebb.
"We still don't feel like that about food."