But everything he does, whether “reading” someone’s mind, compelling a taxi driver to lose London’s best known landmark, or controlling a person’s movements with a voodoo doll, is achieved through the power of suggestion.

Brown is an expert in knowing what makes people tick, and second-guessing what they are going to do.

Psychologists are pretty good at this too. Using techniques just like those employed by Derren Brown, one team in the US has shown how they can convince people they don’t like ice cream.

It’s done by planting a false memory in the mind - in this case a memory of being made sick by strawberry ice cream as a child.

Henceforth, strawberry ice cream loses its appeal. What used to be a luscious treat becomes something that makes your nose wrinkle.
But the experiment was not done for entertainment. The scientists say it could have important implications for dieting and fighting the obesity epidemic.

“This work suggests that the mere belief one had a negative experience could be sufficient to influence food choices as an adult,” says lead researcher Dr Elizabeth Loftus, from the University of California at Irvine.
In the study, 335 students were asked to fill in questionnaires about their food preferences and experiences.

They were told their answers had been fed through a computer which crunched the data to produce individually tailored “profiles”.
The computer read-outs informed one group of volunteers that they had made themselves sick eating strawberry ice cream as a child.

Clever ploys were used to encourage the students to think about this negative experience, thereby reinforcing it in their minds. For instance, they were invited to consider two possible scenarios, once concerning a friend’s birthday, and the other a family outing to a restaurant.
Participants were asked to pick which scenario best matched the remembered incident, or, if they had no specific memory, “what they thought might have happened”.

They were also asked leading questions about the experience, such as “how old were you?”, “where did it occur?” and “how did it make you feel?”
The result was that up to 41% of the manipulated students really believed strawberry ice cream had made them ill.
They even provided details of the experience, such as “may have gotten sick after eating seven cups of ice cream”.

A later food preference test showed that these volunteers had been turned off strawberry ice cream. They rated it significantly lower than they did before, and were likely to avoid it in future.
Dr Loftus points out that it was common for people to develop a food aversion after trying something that made them queasy.
The reaction was already used to treat alcoholics by giving them a drug that made them sick every time they took a drink.

“It may be possible to do something similar with food, but without the physical experience,” says Dr Loftus.
However the study, reported in the journal Proceedings of the National Academy of Sciences, was not completely successful.

The scientists were unable to put students off eating chocolate chip cookies in the same way.
They believe it may be more difficult to form false memories about frequently eaten foods.
Nevertheless, in a previous pilot study, the same scientists were able to persuade volunteers to avoid eating potato chips.

Next they plan see whether people can be led to believe that as a child they loved certain healthy foods, such as asparagus.
Suggestion is also behind the placebo effect, which has been known to doctors for centuries.
Drug trials have to take account of the fact that some patients might respond to a dummy pill with no active ingredients.