Anticipating the taste of food can actually make you less hungry for it and even make it less tasty. Researchers at Carnegie Mellon University found that when people make food for themselves, they tend to "preconsume" it by thinking about the food. This process makes it less desirable and less tasty because of a phenomenon called habituation, which is the reason why humans can deal with extremes; as people get used to the extreme, they become desensitized, and it seems normal. The more preconsumption occurs, the less people tend to eat of the food they made. This is why food generally tastes better when someone else makes it — when another person makes the food, you don't preconsume it, which means that you're likely to be hungrier for it and find it more tasty.
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