Everyone's brain hates it when they lose weight.

Calories have never been cheaper; people have calculated that you can get about 1,000 calories for 90p.

More people are dying from over-nutrition than under-nutrition.

It is definitely an emergency.

Does our brain like us losing weight?

I did the keto diet recently for about two months.

- And... - Why did you do it and why did you come off?

I did it because I wanted to⏤OK, this is interesting, it shows how much of a Neanderthal I am.

- I... I thought I was allergic to gluten. - OK.

So, I thought, I'll cut out all of the things that have gluten in them and I'll try that.

And so⏤I then watch this video online and it talked about the keto diet.

So, I thought, oh, that sounds good, and this guy had lost so much weight doing it, so, I gave it a try.

Now, I lost so much weight, more weight than I've ever lost in my life, like, extreme.

I did it for about eight weeks.

I lost about a stone in weight.

The reason I came off it was because it was hard.

It was hard.

In a... in a simple word, it was difficult.

And... I don't know, I felt like I was fighting against something.

How long ago did you come off it?

And, the crucial information⏤piece of information I'm interested in is, have you gained any weight back?

45 days ago and one of your business⏤I'm joking.

No, I gained so much weight back; I gained...

I didn't just gain the stone I'd lost; I think I gained a little bit more back.

I think I gained a stone and a bit back.

I mean, I'm not in bad shape, but, like, for me,

I went from being absolutely lean, like, I'm ready for mint health, to being like... back to being like, you know, like, I'd say athletic now.

But I gained back the weight I lost and more.

So, this is why I asked the question about the brain.

My brain didn't seem to be on board with me, it didn't seem to want the best for us, and it seemed to want to return me back to my default base state.

Your brain⏤everyone's brain hates it when they lose weight.

It doesn't matter your starting point.

You could start from a point where you are athletic versus someone who's not athletic, couch potato type... phenotype.

The moment you lose a little bit of weight, we're talking even a few pounds, I'm not even talking⏤you're talking about a stone.

Even if you lost 5 pounds, what happens in your brain is, your brain is used to you carrying⏤you or me carrying⏤a certain amount of weight,

the moment your weight starts to go down, as an adult, it goes,

"Ay up," you know, "this is⏤a big flag comes up⏤this reduced... this is reducing my chance of survival."

This is what the brain thinks.

And, so, what it does, is it begins to use strategies⏤not conscious, nothing to do with our brain, anything like that⏤to drag us back up, kicking and screaming to where we were before.

First of all, it makes us hungry, OK?

So, so, so, it makes us... it makes us hungry.

And second, it actually, very, very secretively, lowers your metabolism ever so slightly,

so that even without⏤even eating exactly the same thing, you are now storing more than you're burning, even eating exactly the same thing.

Part of the strategy to get you back up to where you were before.

So, once you were on the keto diet⏤and we can debate how it... talk about how it works and whether it's useful⏤

but once it's on the⏤you're on the diet, your weight goes off, you're able to keep it.

But you said, "Man, I can't do this," and, so, you stop.

And the moment you stop, your brain goes⏤comes back on and starts dragging you back up.

This is gonna be true for pretty much every single diet that is... that is out there: the moment you stop the diet, the weight will come back on eventually.

Why does my brain hate me?

It's what⏤look, this is the brain; you have to remember that that's what's kept us alive.

I mean, we have lived, aside from probably the last 40 years, we probably, most of the time, never had enough food.

Now, clearly, over the past 100 years, we've had sufficient food compared to beyond that.

But you know as well as I do when you turn on the TV and watch "Only Fools and Horses" from the... from the 70s or whatever,

you know, people are skinny; you think, oh, they look skinny.

They don't look skinny; they look... they look normal weight for the time that they're... that they're there.

Whereas we have clearly, over the past 40 years, now, have too much food.

So, this is now a different problem, OK, that we have too much food.

And, so, our brain is trying to respond to this environment, but it's responding in a natural fashion.

'Cause what used to happen was, because there was not enough food, when there's food there, you make sure you ate it.

Otherwise⏤why would you... why would you not do that, right?

So, we have a brain that's wired for a feast-famine environment, feast-famine, feast-famine.

The problem is we live in a feast-feast environment at the moment, and that's the issue.

We have a maladapted brain for a feast-feast environment.

And this is because of how we've set up (the) society.

Because of supermarkets, fridges, preservatives that keep food lasting for longer, and foods more available and cheaper than before, it's more processed, etc., right?

So, so, this is true; now, now, without going all food-Nazi⏤

I mean, you have to remember that the⏤all of whatever you just said, preservatives, pickling, cooking, you start with that then you say,

"Oh, we're goona do highly processed foods, we're gonna do pre-packaged foods, frozen foods, microwave food etc., etc., supermarkets."

It has kept us alive, OK?

We're 7.5 billion people and counting, we need to feed all these people, and this is fine.

The problem is we've now got to the point where the efficiencies, the scales of efficiency in our food production is now so high we can now get⏤calories have never been cheaper.

So, this is... this is the... the issue today.

You can on⏤in this country, for example, in the UK, people have calculated that you can get about 1,000 calories for 90p.

Now, how good are those calories; what (is) the quality of the food of those calories, we're not talking.

We're just talking pure calories⏤because of efficiencies of scale, calories have never been cheaper.

And we don't have to go run after an antelope in order to get... in order to get the calories.

This has kept us alive until it is killing us.

Which is now⏤over the past 10 years, that have been an important inflection point in human history.

You know, previously, we never had enough food.

Whereas now, since the past 10 years, more people are dying from over-nutrition than under-nutrition, and over-nutrition in a bad way.

Because you can be... you can have loads of calories but still be malnourished because you're eating the wrong kind of foods.

And can you believe it?

We are now in a world where there are more people dying because they eat too much than because they... because they don't eat enough.

Is the worldwide trend that we are getting skinnier or fatter?

We are getting fatter as a... as a worldwide trend.

And... and true, that the problems are more obvious at the moment in higher-income countries, OK?

Because... because they studied more and be the kind of food that's available.

But you are gonna⏤but what is the goal of... of a country that is less developed than us, for example?

They want to pull their people out of poverty.

They want to make sure that their poor people don't die of starvation.

They want to make sure that fast food and... and good food, you know, and crap food are available to everybody there as well.

Now, the problem is the moment that happens, you don't switch from being⏤dying of under-nutrition and... and starvation to then, now, dying of over-nutrition.

So, we are at that inflection point where the whole world, very soon, will get into a severe obesity problem and... and we do need to fix the food environment in order to fix that.

Do you consider it to be an emergency?

It is definitely an emergency.

Oh, it is definitely an emergency, and it's an emergency because... because⏤

Let's ask the question: Why is it a problem to have obesity?

Why is it a problem to carry too much fat, OK?

So... so, that is a⏤so, you might think, "Well, it's obvious."

Well, is it?

Because the... the⏤there are issues with gravity when you're too heavy: arthritis, mobility, sleep apnea⏤you can't breathe at night.

But that is... that isn't what kills us, OK?

What kills us is all the diseases that are associated with obesity⏤diabetes, high blood pressure, certain cancers, etc., etc.

That is what kills us, OK?

Heart disease.

And... and so, it is an emergency because with obesity, at a population level as it goes up, then you have millions upon millions of people that... that end up, you know, with diseases.

So, the estimate is that direct cost to the NHS⏤direct cost⏤for treating obesity and related illness is 6 to 7 billion a year, OK, pounds.

That's the direct.

But the moment you take into account the broader economy⏤days sick, etc., etc.⏤it's estimated we are running at 27 billion year.

Just on economic effects on... on obesity.

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