Speaker 1: Welcome to brain Stuff from how Stuff Works. Hey, brain Stuff,
Speaker 1: Lauren vocal bam. Here. You know that ravenously hungry feeling
Speaker 1: you get after going swimming. It feels like you could
Speaker 1: go to and All you can Eat buffet and make
Speaker 1: them rethink their business strategy. But although a salad or
Speaker 1: a granola bar, or even a nice smoothie would probably
Speaker 1: satisfy you, a voice echoing out of the deepest recesses
Speaker 1: of your brain commands you defeat it something warm, an
Speaker 1: entire pizza, perhaps, or two giant bowls of extra brisket please.
Speaker 1: There could be a lot of reasons why we crave
Speaker 1: warm foods when we're especially hungry, but what of them
Speaker 1: probably has to do with the link between smell and taste.
Speaker 1: We spoke with Dr Stephen Secker, an associate professor in
Speaker 1: the University of Alabama Department of Biological Sciences who studies
Speaker 1: the physiological design of digestive systems. He said, hot food
Speaker 1: emanates much more airborne particles than cold foods, and since
Speaker 1: a large part of our taste sensation also involves smell
Speaker 1: hot food, would they or for provide positive reinforcement in
Speaker 1: its selection? Just consider how quickly the smell of smoke
Speaker 1: from a barbecue can make you feel hungry or how
Speaker 1: no matter how tasty it will be, a cold gaspacho
Speaker 1: simply doesn't stimulate the senses like a warm chili. So
Speaker 1: even though we intellectually know that cold soup is going
Speaker 1: to be good and fill us up, our olfactory apparatus
Speaker 1: hasn't yet been appraised of the situation, making it hard
Speaker 1: to get all the parts of the brain on the
Speaker 1: same gaspacho bandwagon. But smell may not be the only
Speaker 1: reason we crave a hot meal more than a cold one,
Speaker 1: or rather, it may signal a deeper reason. Since heating
Speaker 1: food unlocks calories and nutrients we wouldn't be able to
Speaker 1: get eating the food raw, and since our big brains
Speaker 1: are very calorie meaty, our preference for hot meals might
Speaker 1: have something to do with our brains steering us towards
Speaker 1: the most potential calories possible in the moment of hunger.
Speaker 1: According to Richard Rangum, a biological anthropologist at Harvard and
Speaker 1: author of Catching Fire, How Cooking Made Us Human, the
Speaker 1: important comparison is between foods that are cooked and differ
Speaker 1: only in temperature. He said, hot food very likely yields
Speaker 1: more net energy gain than cold food, partly because of
Speaker 1: changes in digestibility. One example is that starch becomes increasingly
Speaker 1: refractory after hot bread than cools, which could be one
Speaker 1: reason why we like hot toast. In the case of
Speaker 1: lipid rich foods, the closer of fat is to its
Speaker 1: melting point when eaten probably the easier it is digested. However,
Speaker 1: Succor clarifies that chewing and the digestive process are both
Speaker 1: pretty good at unlocking nutrients. He said that once you've
Speaker 1: cooked hamburger, for example, eating it hot or cold would
Speaker 1: provide a negligible difference in calories consumed and digestion effort.
Speaker 1: But there's also the nostalgia factor. Smell is the most
Speaker 1: nostalgia triggering sense. Researchers aren't entirely sure why this is,
Speaker 1: but they think it has to do with the physical
Speaker 1: way our brains handle information in the parts known as
Speaker 1: the limbic system. The limbic system includes the amygdala, which
Speaker 1: helps us process emotions, the hippocampus, which processes and stores memories,
Speaker 1: and the olfactory bulb, which processes scent input from our
Speaker 1: nasal cavity. There are direct connections among these three brain bits.
Speaker 1: Studies have shown that sense create more positive and more
Speaker 1: emotional senses of nostalgia than other triggers, and scientists think
Speaker 1: that's because of these close connections amongst scent, emotion, and
Speaker 1: memory in our brains. While there might be some selected
Speaker 1: drive hidden in our behavior to crave cooked food for
Speaker 1: nutritional gains, are cravings, and our susceptibility to a rich
Speaker 1: scent in the air is very likely driven by a
Speaker 1: nice memory of the taste and smell of food right
Speaker 1: off the grill, or the chicken soup that comforted you
Speaker 1: when you were sick as a child. However, even small
Speaker 1: changes in temperature can make a big difference in how
Speaker 1: satisfaction and food is perceived. It's important to remember that
Speaker 1: the texture of foods, and especially fats like those in
Speaker 1: cheese and cheese substitutes, changes drastically within a relatively small
Speaker 1: temperature range. For example, cold pizza, delight, or horror discuss
Speaker 1: h Today's episode was written by Jesselyn Shields and produced
Speaker 1: by Tyler Clang. For more on this and lots of
Speaker 1: other savory topics, visit our home planet, how Stuff Works
Speaker 1: dot com.