The Food Standards Agency (FSA) wants movie-goers to have more information about how many calories are in cinema snacks, and to cut down, as they are often high in fat, sugar or salt.
The agency claims cinemas sell "pretty large portions" and don't provide the option for smaller choice.
FSA chief executive Tim Smith insists cinema food is "a concern".
"Who would ever have thought of the idea of a family needing a wheelbarrow to go into a cinema?" the BBC News quoted him as saying.
He added: "There is a myth that popcorn is calorie-free but that is not the case."
A FSA spokesman said trips to the cinema were "occasional treats" for people, and that cinema meal "only represents a small amount of the nation's calories".
The rep added: "However, the food on offer at cinemas is food that is often high in fat, sugar and salt.
"It is also served in pretty large portions and people don't have a choice to choose something smaller, for example the smallest soft drink on offer can be as big as a pint and popcorn tends to come in large buckets.
"The FSA thinks it's a good idea that people should have more choice. If they want to order a smaller popcorn box or soft drink then it should be available."
The FSA is preparing a calorie labelling scheme some food businesses and will publish its final recommendations in the summer.