Hungry? Your Mind May Be Playing Tricks on You

How much you think you’ve eaten can affect how hungry you are, a recent study finds. 

The study, which was conducted by British researchers, involved 26 people who were given an omelet for breakfast. Researchers told one group the omelet they were eating contained only two eggs, while the other group was told their omelet contained four eggs. However, both omelet had the same amount of eggs — three.

The two-egg group said they were a lot hungrier after two hours than their larger-omelet-eating counterparts. Those who thought they’d only eaten a two-egg omelet ate a heavier lunch of pasta and consumed more calories throughout the day than the supposedly four-egg group. 

The study’s researchers said participants who thought they had eaten a larger breakfast also consumed less calories throughout the day, indicating a link between how perceptions of what we eat can affect how much we actually do. 

Previous studies have shown that a person’s expectations can affect their level of hunger, feelings of fullness and how many calories they consume later on. Pointing to a large body of research, one Princeton University neuroscientist rel="noopener noreferrer" concluded that hunger actually is “a motivated state of mind.” Hunger is controlled by the brain stem, he said, and that while taking in fewer calories is one way to lose weight, being more conscious about the hunger mood and the psychology behind eating can help you better regulate how much you eat.

The British researchers said their study expands on previous research that links personal perception and hunger, because it actually involved solid food and measured how much people ate four hours after they had a supposedly small or big breakfast. With this study, they were able to better track how what someone thought they consumed at breakfast affected how much they ate at lunch. Researchers also took blood samples from study participants to make sure nothing hormonal was at play and could affect the study’s outcome. They found that hormones didn’t affect participants’ physical response to the food, so how hungry they felt largely was a matter of perception. The researchers say future studies should explore how memories of what a person has already eaten affects later calorie intake and feelings of hunger. 

In a way, the study’s results are pretty intuitive. When you think you’ve had a big meal, you’re less likely to follow it up a few hours later with another large meal because you “feel” full. On the other hand, we often trick ourselves into indulging in certain foods, like desserts, because we feel like we need something extra or that it’ll satisfy us and complete our meal. What all the research shows is that hunger is psychological in many ways, and acknowledging and understanding this may help us better control how much we eat and when. The main takeaway here — as researchers say — is that “you are what you think you eat."