Transcriber: Gianna Carroni Reviewer: Denise RQ
At this moment,
the number of obese people in the world
exceeds the number of people who are starving.
Obesity is really a huge problem.
It is leading to diseases like diabetes, heart disease,
some forms of cancer, depression.
And why is there an obesity epidemic?
The reasons are simple.
We just eat too much
and we exercise too little.
Simple as that, right?
I mean, everybody knows it, duh!
Well, wrong.
There are so many other factors affecting our weight.
Today, I will discuss these factors with you.
The good news here is
there are so many other solutions to have a good weight
in addition to healthy diet and exercising.
Let me start with telling you the story of John;
at least, I will call him John.
John was a boy who grew up in the Netherlands.
He was born in a foreigners' family,
and he seemed to be a normal baby.
The only remarkable thing was that he was always crying.
He was always hungry, actually.
Within five minutes after finishing his bottle of milk,
he was hungry again.
And by the time he was eating solid food,
he was eating night and day, he was craving for food, always.
And by the time he was three years old, he was massively obese.
At that point his mother put locks on all the kitchen cupboards,
but still, he was craving, and he was looking in trash cans,
and he was looking for eating even frozen food.
All these years, his mother sensed there was something wrong with her boy,
because her other child was thin.
So she went to doctors,
and she asked for advice.
But they basically told her that she was just feeding her boy too much,
and she felt like being blamed for being a bad mother.
She got frustrated.
And at some point, she get referred to the Erasmus Medical Center in Rotterdam.
And she saw there my colleague, Erica van den Akker,
who is a pediatrician;
and she found that John
had a genetic abnormality in his hunger hormone system,
the MC4 receptor defect.
What that basically means is he had never the feeling of satiety,
he was never full.
This diagnosis was really important for John's mother,
because they really suffered from the stigma,
because they were accused of having a weak character.
After that, school, social networks,
they started to support John and his mother,
and actually for a while, his weight stabilized.
He's now a young adult, and I see him as a doctor in my outpatient clinic.
And he is still struggling with obesity.
Currently, medical treatments are under development for patients like John
so I hope to being able to help him in a medical way in the near future.
You would think, "Well this is rare."
That's true, only 2% of the obese people
are carrying a genetic abnormality as the MC4 receptor like John,
but there are other genetic variants that would make you much more hungry
or decrease your metabolism.
So, if you see someone eating extremely much,
maybe we should think twice before judging.
So, it can be in your genes,
and the genes affect your hunger hormones,
but did you realize that crash diets also affect your hunger hormones?
Very low-calorie diets can also influence your hunger hormones and increase them.
In the short term, crash diets work,
they reduce your weight,
but the problem is that then, your hunger hormones will increase,
and also your satiety hormones will decrease.
Satiety hormones are the hormones that make you feel full.
We always think it's stretch on the stomach that you feel full,
but that's only part of the story, actually.
It's your gut giving a hormonal signal to the brain,
telling it you are full,
and then you stop eating.
So when this signal is not adequately being provided to the brain,
you automatically eat more.
So, basically, after a crash diet, you are hungrier.
And that's even so in the long term.
It has been shown even a year after a very low-calorie diet,
still the hunger hormones are higher.
So, what about a conscious choice of food
or having a weak character?
The biology is telling you to eat more.
The weird thing is your basal metabolism
is also being decreased by a crash diet.
So basically, you are hungrier,
but you burn not that much calories as you used to do.
That's the perfect prescription, of course, to regain your weight,
and that's what we call the yo-yo effect;
we know how it works now.
So, basically, crash dieting is another risk factor for obesity.
Food can also affect your hunger hormones,
but also your fat.
Let's do a small experiment here.
Imagine a box in front of you.
And in this box there are chocolates.
There are white chocolates, brown chocolates, they're shiny.
You smell the chocolate right now.
And imagine you are taking one.
You are taking one of the chocolates right now.
And you take a crunchy bite.
And now you start feeling...
You taste the soft, sweet praline and chocolate in your mouth, right now.
(Laughter)
You are making hunger hormones right at this moment.
(Laughter)
Unless you just had dinner.
But that means, when we go out now, for food,
and we see sweets,
we are much more likely to choose the chocolate or sweet foods,
rather that an nice green salad or what you know is much healthier to eat.
So, this choice of food is not that conscious as we think it is.
Your biology is driven by your thinking.
The food industry perfectly knows this:
they use advertising and all these visual stimuli
to stimulate also your hunger hormones, making us eat differently
than we maybe think it's good for us.
But you can also benefit from it.
Actually, it is the solution also for obesity,
because we know that saying, "Well, eat less," is not working;
but what is effective is changing your thoughts
by cognitive behavior therapy programs.
That's effective.
I told you now about the biology and hunger hormones.
But there are other factors in our environment
which affect the amount of food we eat.
For example, our social cultural background.
We know that in some cultures eating and food is hospitality.
So, imagine that your neighbor has stood in the kitchen for three days,
cooking a delicious meal for you,
and invites you over.
Well, it is socially not really acceptable not to eat all of it,
and just take a tiny bit.
So also your cultural background may determine the amount of food you eat.
Things have changed in the last decade.
In the past decade, we became much more stressed.
If you are stressed, we know your body is producing
more stress hormones than usual.
In particular, the stress hormone cortisol,
if you are stressed for a prolonged period of time.
We know that if you have high levels of stress hormone,
that makes you fat.
Abdominal fat mass will increase.
But that will also increase your appetite.
In particular, your appetite for calorie-rich foods.
So, that's maybe why we grab a candy bar when we are stressed.
We don't know exactly what's causing what, actually,
because this sugar rich food seem also to stimulate our stress hormones.
So we found -
our team and also others found that obese people have
higher levels of this stress hormone.
So maybe when you're obese, you get into a vicious circle
of having elevated stress hormone cortisol stimulating the calorie-rich food,
and that in its turn, stimulates again your stress hormones.
So, psychological stress can stimulate your cortisol,
but also specific foods,
and in particular, also drinks like alcohol.
We know alcohol's inducing an increase of your stress hormones,
increasing your abdominal fat mass.
But there's more which is affecting your stress hormones,
and that's sleep.
In the past decades, with increase of obesity,
we also reduced the number of hours we sleep.
The lack of sleep is also activating our stress system,
increasing our cortisol, but also deregulating other appetite hormones.
So the net effect of a reduced number of hours of sleep
is weight gain leading to obesity.
So, the solution here for obesity - additional solutions -
may be to reduce your stress level
and also to improve your sleep hours.
And there's more.
In this world, nowadays, we take a lot of medication.
I will tell you the story of Mary.
Mary was a 20-year-old young woman
who came to my outpatient clinic, because she gained weight.
She gained actually a lot of weight, 20 pounds within ten weeks,
and she did not understand why.
She entered my room, sit down, and she started crying.
Because she was eating very healthy,
and she was exercising every day.
And the reason she was so sad
was actually because she was a life-style coach herself.
She was actually telling people
how to eat healthy, how to exercise well;
and now she felt that her clients didn't trust her anymore
as being a good life-style coach, because she was gaining weight herself.
And after some testing
- she had received corticosteroid injections in her knee -
she had a knee problem because she was exercising very actively.
We know that corticosteroids are an artificial version
of your stress hormones.
And remember, your stress hormones increase your abdominal fat.
And may also increase your appetite.
So, she suffered from a really extreme side-effect of medication.
And actually this is rare.
I see only a few patients like this a year.
But on the other hand,
we use a lot of medication;
some of the medication have as a side-effect also weight gain,
maybe in a more subtle way than in this case.
But still, particularly, obese people use more medication.
So, if you are obese, and you want to lose weight
and you are just about to enter a treatment program for your obesity,
and you use medication,
it may be worthwhile to discuss with your doctor
whether that medication indeed have weight gaining side-effects.
And then to discuss whether the dose can be reduced
or the medication can maybe even stopped
to make your treatment much more effective.
The last topic in our environment I will discuss is brown fat.
Who of you ever heard of brown fat?
Please, raise your hand.
Well, some of you, but most of you not.
So well, actually, brown fat is the good fat.
We all know the white fat, that's what's on your hips, and your belly,
and that's unhealthy fat, which is making you sick.
But the good fat literally converts calories into heat.
It burns your calories.
Well, that's fantastic!
That's the Holy Grail!
We all know these people who can eat a lot,
and they never gain weight.
They have a good chance of having a lot of brown fat there.
In the past, we actually thought that only babies had it,
and we would lose it in adulthood.
But it has been discovered a couple of years ago
that as adults, we also have brown fat.
It's color brown because the little energy factories in the cells
color the cells brown; therefore, it's called brown fat.
And it's located around the neck, the spine, between the shoulder blades,
and around your kidneys.
But obese people have less of this brown fat.
So they, basically, cannot burn that much calories as slim people do.
But there is good news,
because it has been shown that also people with obesity
can actually stimulate their brown fat tissue.
You can do it either by exercise,
which is hard if you are really massively obese,
but you can also do it by cold;
by cold temperature.
You don't need to worry, you don't have to sit in a freezer for a day.
(Laughter)
But actually already is enough - it has been shown -
that if you spend for a couple of weeks, for six weeks for example,
two hours a day at 17°C, which is 62°F,
just below room temperature,
then you already activate your brown fat,
and you will lose some kilograms of your white adipose tissue.
So you lose the bad fat.
So, maybe in the past decades,
we were spending too much time in the heat,
and we have not enough cold exposure -
maybe due to our convenient winter clothing and our well insulated houses,
and driving around in well heated cars.
Maybe we should just go out more often and take our coats off,
and tell our kids to play outside without their jackets.
Looking at all these factors:
stress, and sleep, and medication, and thoughts, and crash dieting -
I think the problem of obesity, and of the obesity epidemic,
is that we think too simply.
The solution here is look at all these factors
and change them where possible.
It is now time to not longer judge people with obesity
but to start supporting them.
And that's the way we will combat obesity much more effectively.
Thank you.
(Applause)