CHAPTER 4
Hunger and Satiety Intermittent fasting gives you free reign to eat what and when you want as long as you’re within your eating window. Still, it’s worth embracing my number one rule for weight loss: if you’re not hungry, don’t eat. I don’t care if it’s dinner time. Your body doesn’t seem to need food, so why feed it? Consider yourself lucky for the extra hour, and go do something else! Take a walk, call a friend, clean your house, organize your vacation photos—use the time for something other than adhering to a made-up meal schedule. This urge to eat on a socially acceptable schedule is something we really buy into as adults. Children have a much better understanding of their physical need for food, and if you watch them, you’ll notice they eat at irregular intervals, sometimes eating a lot, sometimes eating two bites or simply rejecting a meal outright (much to their parents’ concern). Yes, they’re growing, but that’s not the only reason they eat that way. They are also better at responding to what they need and don’t need when it comes to nourishment. Some very clever studies have shown that at the age of three, children are able to tell when they’re full and stop eating, whereas by age six, children start to become as confused as adults about when to stop eating. They respond more to whether there is food in front of them than to whether they’re hungry. They begin to eat more than they need, and they will probably do so for a lifetime. But eating just because food is available or because it is a certain time of day is not the best strategy for weight loss. Feeling hungry sometimes is okay. No harm will come to you. But what makes us hungry anyway? Is there anything we can do to lessen sensations of hunger when we diet?
How Hunger Works Many factors contribute to a feeling of hunger and the desire to eat or stop eating. Internally, hormones released in response to nutrients from a meal signal that the body has had enough nutrition, which prompts us to put down to the fork. A drop in nutrient availability (as happens when it’s been a while since a meal, or after intense exercise) will turn up the appetite, as will certain hormones released in response to circadian rhythm or nutrient balance. Externally, the smell of food or the sight of an appealing dish can make us start salivating, signaling the beginnings of digestion and the body’s anticipation of food to come. After you’ve eaten a lot, these same sights and smells might make you feel a little queasy, reminding you that fullness or satiety is just as real a sensation as hunger.
Ghrelin, the Hunger Hormone One of the most powerful tools the body has to persuade you to eat is the hormone ghrelin. Ghrelin is often called the “hunger hormone” because it’s produced by an empty stomach to tell the brain to increase
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