Nope. Psychologists say that simply thinking about eating more fruit won't make you eat more fruit. But thinking about eating a cookie or breakfast bar will make you eat more of those.
The study went like this: Participants were asked to imagine eating a piece of fruit, or a cookie. Then they were asked to answer questions about what kinds of foods they liked, right after the imagination exercise and again a few days later. Researchers also asked participants if they had eaten a piece of fruit or breakfast bar since the experiment. Christian Jarrett at Research Digest explains the results:
Once the researchers controlled for background factors (such as the possibility there were more fruit lovers in one condition or the other), they found that the fruit imagery task made no difference to participants' intentions to eat fruit, no difference to their choice of fruit as a reward, nor their consumption of fruit the next day, as compared with the control group who didn't perform the imagery. For the biscuit bar group, the imagery task increased their intentions to eat biscuit bars in the future, but didn't actually alter their consumption (as compared against the no-imagery control group).
So even if you think a lot about eating fruit, it won't be enough to make you actually grab that apple. But a thought about cookies will be enough to grab one.
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