Why do I always have room for dessert?

Speaking with Chris Smith, Giles Yeo answered this question from Rosie...

Chris - Indeed. Now we've all been there haven't we; absolutely stuffed, and then someone comes along with the sweet trolley and then says, "would you like some of this delicious chocolate cake?" you miraculously find a sort of cream-cake-sized corner that's vacant in your stomach... How does this all work?

Giles - So I mean, we know this "dessert-tummy-phenomenon". We go out - I bet you - by the middle of the second course of a meal that you're actually eating - you will have reached your metabolic need for a day! Which means that you would have made up the calories - you know a big meal, not a Michelin star fancy fancy...

Chris - "Nanofood!"

Giles - Exactly. Exactly.

Chris - So a decent portion!

Giles - Yes really full... yet, when dessert comes, we actually eat it. The more important question actually about that is, why is it specific to desserts? Because if, say, you had steak and chips and you're really stuffed, and the waiter comes by and says, "More steak? More chips?" you go "dude, no, I feel like puking!" and I won't actually eat it. Yet, we'll actually have the dessert! Well here's the point right when we actually throw back to the Serengeti, when we're dragging an antelope back, and you had to eat more than you needed, because you would never guarantee to get the antelope.

Chris - There's no "Serengeti supermarket".

贾尔斯-塞伦盖蒂没有超市。的问题lem is something like protein is very bulky. Right. So it goes in. So what happens? Your brain begins to change the quality of the calorie that it actually likes to eat. It begins to increase the caloric density of the food that you eat. So therefore, for every given gram you'll get more calories. You can stuff it into all the little nooks and crannies. What is calorically dense? Fat and sugar. What's high in fat and sugar? Desserts! It's a hold-back from the Serengeti to keep yourself alive even when you've had so much food. And lest you think it's human-specific, look at the grizzly bears doing the salmon run. Okay. So they start getting ready for hibernation. They start by eating the whole salmon, like Garfield right, the whole thing. But, again, as they get fatter and fatter they only eat the skin and the fat underneath it. They increase the caloric density. They don't have dessert but that's the phenomenon!