What springs to mind when you hear the words ‘Human Appetite Lab’?
Benches full of bubbling test tubes? Conical flasks full of rainbow-coloured liquids?
Plates full of ‘bush-tucker’, designed to test our appetites to the limit?
Maybe you’re a bit of a sci-fi fanatic and you noticed that its initials spell ‘HAL’, and you are visualising evil computers a la 2001: A Space Odyssey?
If any of these are what you pictured, you might be disappointed to learn that it is in fact no more than a small suite of cubicles attached to our clinic, where we sometimes ask volunteers to eat a meal alone and in silence.
What’s the point in this? Well, we can learn a lot about the human appetite by getting people to concentrate on what they’re eating without any distraction from outside stimulus.
To help with some clinical staff training, I had a go in the HAL myself, and here’s how it went:
3pm: I wait outside the HAL for a member of the clinic team to let me in. I’m not allowed to knock on the door, as this would break the silence and might affect the other volunteers who are already eating. I realise that this ‘no outside stimulus’ rule is taken very seriously.
3.10pm: After being shown into my cubicle, I must wait in silence for 10 minutes before my meal is brought to me. The space is small without being too tight or claustrophobic, and the walls are plain white but for one canvas, which has an inoffensive picture of some leaves in pastel shades. Actually, I really, really enjoy this part! As a full-time-working Mum, I cannot remember the last time I sat for 10 minutes with nothing to do and no distractions! I almost wish I could stay and enjoy the peace a little longer, but I can smell food and my stomach is growling. (I’m usually a lunch-at-12 kind of girl, so I am ready for whatever’s on offer!)
3.15pm: One of my clinic colleagues brings in a tray full of food. Emphasis on FULL! There’s half a sliced cucumber, a dessert-bowl full of salad leaves, another full of yoghurt and a whole family-sized lasagne in its plastic tray. I’m not exaggerating when I say there’s enough here to feed four. Good thing I’m hungry!
I’m told that I must take vertical strips from the lasagne, transfer it onto my plate and eat everything on my plate before taking any more. I suppose that this will allow the clinicians to accurately measure how much I’ve eaten. Before she leaves, the trainee tells me that the purpose of this exercise is to eat until I feel ‘comfortably full’, and that if I do finish all of my lasagne before I reach this point then they will bring me more. Wow!
3.25pm: I’ve munched my way through one sliver which is about 1/5th of the width of my family lasagne. It was delicious! I nibble a bit of cucumber and think about eating some more. And then I realise that I don’t know whether I am ‘comfortably full’ or not! I could definitely walk away now and feel satisfied. But I’m sure there’s room for more! I have a long think about calling it a day. But the food is delicious, it’s free, and if I leave now I will be wasting over ¾ of a lasagne! So I cut one more small sliver. Yum!
3.35pm: As I waddle back to my desk, my stomach gurgles again but for a very different reason. I have definitely pushed myself to the less comfortable side of ‘comfortably full’.
So my experience of the Human Appetite Lab was a bit of an eye-opener! Firstly, it made me realise that our appetites are very sensitive to external factors. Even alone, in a silent room with blank walls, I still responded to cues outside of my own body – namely, a sense of obligation not to waste a free meal! Secondly, and a little worryingly, I learned that I am used to valuing these external cues over my body’s own reaction to food. I genuinely struggled to recognise when I was full.
It’s a common problem. When deciding how much of a meal to eat, most of us are influenced in some way by what’s going on 
around us. You are likely to eat more if your dining companions are really enjoying their meal, and less if they complain about the food. It is very common to feel obligated to eat everything on your plate, even if this means eating more than the body actually wants or needs. If you eat in front of the TV (and let’s face it, who doesn’t), you can be influenced by what you are watching; for example, you might eat more if you tune into Nigella Lawson and significantly less if you’re watching Embarrassing Bodies. You might even keep picking at a meal which you’ve ‘finished’ until a show ends, or there’s an ad break, an opportunity to scrape your plate and get out of ‘eating mode’.
This is why the HAL plays such an important role in some of our studies. Obesity is on the increase, and it contributes to a huge range of diseases, from type 2 diabetes to cancer. There’s an increasing demand on the Pharmaceutical industry to help find solutions to the obesity epidemic. One way to tackle it is to create treatments which reduce the human appetite, and by reducing the number of external stimulus which can affect us, the HAL helps us to establish whether the drug is working. Simple, but effective!
Would you like to eat a meal in the HAL? Give us a call on 0113 394 5200 and ask us about our upcoming food effect studies!