Why do I feel hungry?

Darren Ratcliffe (0:04)

One of the things that I've learned since losing weight is if I keep things predictable, they're a bit easier to manage.

That makes sense? So I've put a couple of baked potatoes in the air fryer because it's easier to make a couple, and then I can put them in the fridge and save them for later. So what I tend to do most days is have something similar. So it's easier and more predictable.

Ruth Alexander (0:31)

This is Darren Ratcliffe at home in Manchester, England. For a time he used weight loss medication. Now he tries to manage what he eats by himself.

Darren Ratcliffe (0:41)

I've in tuna today and I've got some sweet corn as well. And then usually what I do just to help fill it out a bit is make some salad to go with it.

Mixing bowl.

Ruth Alexander (0:59)

So before you went on the medicines, how would you describe your appetite?

Darren Ratcliffe (1:04)

Constant. Constant and non-stop.

Ruth Alexander (1:08)

Why can appetite feel so strong for some of us? And what determines when you've had enough?

This is The Food Chain from the BBC World Service. I'm Ruth Alexander and in this episode, I'm exploring what drives your appetite and how much control over it you really have.

Darren Ratcliffe (1:27)

If I start thinking about eating food, I can be hungry.

I get really hungry and I want something to eat. And a lot of people don't understand what that feels like because they don't have it. And it's a really weird thing. It's a difficult thing to manage. It's how I've always been since I was being a kid. So it's not a new thing. It's just, I don't know, it's just how I am, I guess.

Ruth Alexander (1:50)

And then when you started taking the medication, how did your appetite change?

Darren Ratcliffe (1:56)

It changed instantly. Well, not instantly, a couple of days. And it just went. And there was times that I've said to friends, I don't think I've ever two days. And I had, but it was just like some berries or a little bit of fruit. And that's not really anything substantial. And in fairness, it worked quite well. So in total, I lost around four stone when I was on them.

And then it was at a time when the cost kept increasing and increasing.

So I decided it was time to stop. And then within a week and a half of stopping taking them, put a stone on fairly quickly.

Ruth Alexander (2:34)

About a quarter of the weight you'd lost?

Darren Ratcliffe (2:36)

Yeah.

Ruth Alexander (2:36)

What was your appetite like when it came back?

Darren Ratcliffe (2:39)

It was like making up for lost time.

Ruth Alexander (2:42)

So what is appetite exactly? Professor Giles Yeo, a geneticist at the University of Cambridge in the UK, thinks of it as a triangle in your head.

Giles Yeo (2:52)

Appetite encompasses at least three different phenomena. It encompasses hunger, and we understand a grumbly feeling in our stomach.

It encompasses fullness, and that is regulated by a different part of the brain, completely different circuits, how full you are. And it encompasses reward. So in other words, the lovely feeling you actually get from food. How much do you actually like food? And it's another part of the brain. So hunger is regulated by the hypothalamus. And for those of you who don't know where that is, bridge of the nose, base of the brain, and it sits right above the pituitary. And human beings is about the size of your thumbnail, shape of an almond. Fullness, and this involves fullness, comfortably full, uncomfortably full. Oh my god, I feel so full, I feel like puking. And that's the rear of the brain, the lizard brain, so to speak, where your head meets the neck. And reward is this, is this element on top. And appetite sits in the middle.

These three parts of the brain separate circuitry, but they all speak to each other. And how they speak to each other is your appetite, your appetite towards food.

Ruth Alexander (3:54)

So appetite is more than just hunger, and hunger is more than just, I need food. Here's registered public health nutritionist, Federica Amati, who's from Imperial College School of Medicine in London, and author of The Appetite Reset.

Federica Amati (4:10)

The three most commonly described types of hunger are hedonic hunger, homeostatic hunger, and a novel, a newer type, which is known as microbiome-derived hunger. And so homeostatic hunger is what you'd consider your traditional hunger. It's what you see in newborn babies. When their energy starts to dip, they cry until you feed them. And so this might look like genuinely haven't eaten for a while, and so your energy levels start to dip and your ability to focus starts to dip, and you need to just eat some food to replenish your blood glucose levels, to replenish energy available for your brain and for your body to be able to continue working as it likes to.