Peter Rogers, a nutrition and behavior professor at Bristol University in England, described the latest findings as "fascinating," adding that they could lead to a new way to treat people who suffer from obesity.
"In many ways we understand how appetites are controlled and how food preferences develop," Rogers said. "But what we don't have are the tools for changing our preferences."
He says the research taps into our aversion to certain foodsa strong influence on how our food preferences are shaped.
"It's well known that if we eat something and get sick afterward, the likelihood is that we develop an aversion for that food," he said. "It can lead to quite a powerful dislike of the food that was associated with the sickness, even if the individual is consciously aware that the food itself didn't make them sick."
"A lot of food aversions occur in childhood," Rogers added.
He says this may be because children tend to get sick more often and also because they have less control of what they eat. "For instance, they can often have a very strong dislike of banana, possibly because it's often used as an early weaning food," he said.
Rogers says there are possible lessons here for parents keen to instil healthy eating habits in their children.
"It might be that an overenthusiastic parent feeds them rather too much of something [that's healthy]," he explained. "We can do more harm than good in that way."
Parents often use dessert as an incentive for children to finish their vegetables. "It ought to be the other way round: If you eat your ice-cream you can have some sprouts," Rogers said. "That way the child will think sprouts must be pretty good."
The Asparagus Experiment
So can a good experience of a healthy food also be planted through false memory?
The U.S. researchers believe it can. They conducted another experiment where they tried to make people believe they loved asparagus the first time they ate it as children. Again the team's success rate was as high as 40 percent. Elizabeth Loftus says parents could try playing a similar mind game, falsely telling their children they enjoyed certain wholesome foods when they were younger.
Critics might question the ethics of lying to change a person's behavior, even if the fibbing could lead to improved health.
"Of course this is a provocative idea that will give people pause," Loftus said. "But in our society we have found other situations where we've had to 'force' people to do something for their own good."
She cites seat belt laws as an example. "Until [wearing seat belts in automobiles was] made mandatory, many people skipped the belting. Now people have accepted the idea and many think it is a good idea."
The new psychological treatment could help tackle the growing problem of obesity in the U.S. and elsewhere, Loftus says.
Obesity significantly increases the risk of many diseases and health conditions, including heart disease, diabetes, and breast and colon cancer.
The latest figures from the U.S. Centers for Disease Control and Prevention show that 30 percent of U.S. adultsover 60 million peopleare obese. And the percentage of young people who are overweight has more than tripled since 1980.
Obesity is associated with at least 112,000 deaths annually and adds an estimated 75 billion dollars in medical costs each year in the U.S., according to the CDC.
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