Trying to cut out all thoughts of your favourite, fattening food may actually make you eat more, claims research.
Suppressing chocolate cravings boosted consumption
Women who tried to stop thinking about chocolate ate 50% more than those who were encouraged to talk about their cravings.
This "rebound" effect could also apply to smokers, say the Hertfordshire University authors in Appetite journal.
Experts at Weight Watchers said a "varied diet" was the best way to lose weight.
Dr James Erskine, who led the project, recruited 134 students who were asked to either suppress all thoughts about chocolate, or talk about how much they liked it.
They were then asked to choose from two brands of chocolate, believing that it was this choice that was being recorded by the researchers.
However, the quantity they ate was recorded instead.
Women who had tried to suppress their cravings ate on average eight chocolates, while those who had talked freely about it ate five.
Men did not show the same effect, with the group told to talk about the snack eating more.
Dr Erskine said: "There is a lot of research into the idea that when you suppress a thought you end up thinking about it more.
"However, this the first concrete evidence of how this works in relation to food choices."
He said that the best advice to people trying to cut down on a "sinful" food was to try not to completely avoid or think about it.
Emma Hetherington, from Weight Watchers, suggested that a balanced of different food types was the best way to control weight.
She said: "The research is not a surprise to us.
"We know psychologically, if you set yourself an unrealistic goal, such as 'I'll never eat chocolate again' or 'I'll never have a glass of wine', automatically that is all you will think about."