Hunger (in the Plural)
Nutrition has a lot to do with hunger and satiety: we eat when we’re hungry, and we stop when we’re sated. Sounds logical? It’s not quite that simple.
Jason Fung(1), a Canadian physician and author of the book “The Hunger Code"(2), identifies three different kinds of hunger that help a great deal in looking at the problem from different angles: today we’re looking at hunger in the plural.
1. Homeostatic Hunger
This is the hunger we usually assume in the simplified picture: the body legitimately demands food - because it needs either building material or fuel. I lean towards the body normally needing building material: we all have more than enough fuel on board once we are above 5% body fat(3).
This hunger builds up slowly, and can be satisfied with almost any real food that contains the needed nutrients and building blocks.
2. Hedonic Hunger
This hunger is about pleasure and emotions. It is driven by the brain’s reward centre and dopamine. This hunger likes to strike suddenly, for example when the smell of freshly baked bread drifts past your nose, or you spot the bar of chocolate in the cupboard. Everything was fine until then, but all of a sudden there is a powerful craving that absolutely demands to be satisfied.
“I’ve got a separate stomach for dessert” is a common remark: you may have just stuffed yourself to the brim, but when dessert is served, suddenly a little more fits after all. If, instead of dessert, another steak were served, nobody would touch it.
3. Conditioned Hunger
Routines, upbringing and habits trigger this hunger. You don’t eat because you are hungry, but “because it’s 12 o’clock”, “because popcorn belongs at the cinema”, “because a meeting simply calls for meeting biscuits”.
Pavlov’s dog(4) is an artificial and very well-known variation and illustration of conditioned hunger.
Humans are very easy to condition to this hunger: from the earliest childhood, sweets are a reward and create contentment. At some point - rather quickly - this relationship flips, and dissatisfaction gets treated with chocolate. Who doesn’t know the feeling?
Bonus: 4. The Dietary Guidelines
There is still one more implicit view of hunger I keep running into - derived from the usual dietary guidelines: by their logic, hunger would be the absence of fullness - let me explain:
It seems to me the ultimate goal in the dietary guidelines is food that is as low in caloric density as possible - that is, food with the largest possible volume for the same amount of calories. In this environment, nobody can imagine, for instance, that butter - almost pure fat, with high caloric density - has a big effect on homeostatic hunger, satisfying it with fat-soluble vitamins and bioavailable micronutrients it also contains.
Instead, the advice is to eat high-volume foods - to “fill” the stomach. This feeling of fullness is equated with satiety - and conversely, the absence of fullness would be: hunger.
This is also the principle behind stomach reduction surgery: “We don’t trust you to use your own stomach correctly, so we’ll take part of it away from you” - the ultimate genuflection before the calorie balance.
Why the calorie balance is worthless
Caloric Balance: Cause or Effect?
An invitation to reverse the causality: why explaining weight loss through reduced calorie intake is not very helpful
Read more →Not surprisingly: I am - also from personal experience - very much opposed to “lack of fullness” as a cause of hunger. To me it’s the weakest and least plausible definition of hunger.
What Does This Mean?
Highly processed foods(5) are often deliberately composed to throw the body’s signals into confusion: they frequently target all three of the kinds of hunger mentioned first, and never the feeling of fullness.
What’s wrong with satisfying my real, hedonic hunger with dopamine-releasing products, to reward myself?
The problem is that these foods don’t satisfy hunger for long, but do carry their “rewarding” effect: at the latest when hunger comes back (but happily also without hunger ever having been lowered: the portion size for gummy bears is: one bag. For chocolate: one bar. For crisps: one bag. Possibly two, but always complete bags, never halves).
Does anyone know the feeling of just eating on, even though the body is already signalling that it’s enough? But because there’s still something in the bag, the hand just keeps reaching in.
And this applies, to a different degree, not only to obviously superfluous things like gummy bears, but also to many other highly processed foods.
It becomes especially problematic when such foods deliver a lot of fuel, but minimal building material.
The difference between building material and fuel
Overfed and Undersupplied
An alternative interpretation of hunger: what if we’re not hungry because we need to eat, but hungry because of what we ate? A useful mental model…
Read more →The Way Out
Back to the beginning: “We eat when we’re hungry, and we stop when we’re sated”. I consider that as understandable as it is wrong: this sentence pretends there is only one hunger, and not three. That’s probably why the usual dietary advice considers only the fourth hunger.
Whoever recognises which kind of hunger is calling has taken the first step towards responding to it: which hunger is calling? Does it build up slowly, is it better satisfied with an egg than with chocolate: it’s homeostatic hunger. Did it strike suddenly with the smell from the bakery? Hedonic (and a little conditioned). Did it come with a glance at the clock? Conditioned.
Sounds like bookkeeping, but it’s the real lever: willpower means fighting against all of them at once - a fight you can only lose in the long run. Instead, you realise that more often than not your hunger not a need for nutrients (homeostatic hunger), but one of the others.
What remains in the end is the one hunger that truly calls for food: the homeostatic one. And it immediately raises the next question: what actually belongs on the plate to satisfy it? The largest possible volume with low caloric density, or the most nourishing dish possible, one with high nutrient density?
I think: that’s not even a question.
