The role played by ghrelin and leptin in cognition and appetite regulation

There are countless books, articles and videos that give you great advice on how to overcome your fear and become a better public speaker. Adding one more article to it is hardly going to help you or give you anything more than even a little Googling would, so I won’t even try.

What I will do however is give you the one tip you truly need to know that will save your behind each time you are called upon to speak in public. First things first, however, a little explanation and some framing to help you understand it better.

I do a lot of public speaking. I spend most of my time in Greece these days, because of the weather and the allure of having a seafront just ten minutes’ walk away from my house, so most of my public speaking requires jet planes and the crossing of many time zones. When I do speak in public my brain is still locked in a timezone that’s several hours on either side of my bed time and I have still not had enough sleep to recover or enough time to acclimate.

Because I have to make sense to those who pay money to listen to me I need to be on my “A Game” regardless. So the tip I am about to give you is what I developed for survival.

Now, the framing. Public speaking is always terrifying. It doesn’t matter when or where it takes place or what you’re going to talk about. You will be the person in the spotlight looking at a room full of strangers and wishing you were elsewhere. Your heartrate will be up. Your stress levels will high. Your brain will want to shut down and revert to a state of infantilism at a time when you need its higher functions the most. During these times we tend to try and find some pattern we are familiar with to hide behind, some kind of routine: we might have a drink beforehand (depending on the time of day), or go to lunch or grab some breakfast. These are all things that will quieten the body down and calm the trepidation of the brain and I will urge you all, should you have to speak in public, to resist them at all costs.

When you are out there, facing the crowd, no matter how tired you are, how little sleep you may have had or how much anxiety you might be feeling, what you want is to be two things: Hungry and caffeinated, in that order.

That’s my secret of survival. You may not be able to get coffee into you for many reasons: There may not be time, you may not know where the cafeteria is, the set up may not allow you to or you may simply not find a person who can help you out here. You can survive it no problem provided you are hungry.

That means no breakfast if you’ve flown in the night before and are speaking in the morning, no lunch or breakfast, if you’ve flown in the night before and are speaking in the afternoon, pretty much nothing if you happen to be speaking in the evening, definitely no airline meals if you’re flying in and you’re expected to stand before a crowd an hour or two after landing. You get the message.

This has worked for me for over ten years now and I have stood before roomfuls of high-level executives and taken questions after a forty-minute speech after a fifteen hour flight and still killed it. I have delivered three-hour workshops to corporate teams having crossed the Atlantic just the night before without getting tired, mentally confused or emotionally drained because I was firing on empty.

You may want to use my direct experience as proof of concept but at the back of your mind, quite rightly, you may also think that a sample of one person is a little small to make a generic case. And you’d be right. I may be neurobiologically messed up, I might have some kind of mutant gene in my DNA or, worse, I might just be enough of a loon to put myself through these things.

So, to back it up, I give you a little hard science:

A team led by Tamas Horvath, chairman of Yale’s comparative medicine program, had been analyzing the pathways followed in mouse brains by ghrelin, a hormone produced by the stomach lining, when the stomach is empty. To the scientists’ surprise, they found that ghrelin was binding to cells not just in the primitive part of the brain that registers hunger (the hypothalamus) but also in the region that plays a role in learning, memory and spatial analysis (the hippocampus).

Basically, the study says that, hunger makes us smarter and more energetic by activating a hormone that promotes the acceleration of cognitive processes in the brain and metabolic processes in the body. Because ghrelin promotes homeostasis, i.e. the most stable configuration of all the interdependent elements that make up the mind and body, its presence is sufficient to overcome any short-term disadvantages like fatigue, sleeplessness or a brain and body struggling to adjust to a different time zone and deliver at peak cognition.

Because the action of ghrelin overlaps that of leptin in the hypothalamus the overall effect is a massive energy boost that keeps the brain and body revving without crashing for hours on end, particularly when that is combined with a strong cup of coffee or two.

I came across it accidentally and with experimentation refined it to suit my hectic public speaking schedule and global travel it can work just as well if you’re giving a speech to your local college or business club. When we discover a hormonal secret, using it to our advantage is the smart thing to do.