The
experiment has been reproduced many times on dozens of mice. For researchers,
this strange behavior can simply explained: without omega-3 fatty acids, the
brain does not develop and function normally. They are needed because the
brain‘s ‘gray matter’ is 90% fat which it cannot produce itself. The brain is
the organ, after adipose tissue, that is the richest in polyunsaturated fatty
acid? or omega-3. So omega-3 is indispensable because the body can not make it.

 We
have to ingest it. It has to come from the diet. Oily fish, organ meat,
vegetable oils, and seeds and nuts such as almonds have long been the main
sources of omega-3 for humans. But these foods have become scarce in the
cuisine of industrialized countries. The amount of omega-3 that enters the
brain is crucial for making brain cells more efficient.

 Because when these fatty acids are
incorporated into the membranes of nerve cells, they improve their electrical
properties. In omega 3-rich neurons, the signals propagate faster. The network
is more efficient. Depriving the brain of omega-3 is linked to a risk that it
will function less well. The general population is deficient in omega-3.

We have insufficient intake of omega-3, so
it’s important to pay attention to it. especially in the pre-natal
developmental period, when omega-3 is incorporated in large quantities into the
brain. Also, in adolescence, since adolescence is a particular time of change
of diet.

 And,
during aging where the incorporation of omega-3 into the brain tends to be less
effective, so we must increase its intake. The first rule for a brain to run at
full speed is: avoid deficiencies. But good nutrients and a varied diet should
be available. What happens to neurons when meals are poor and, above all,
always the same? That is a problem that is now affecting the wild-living
European hamster, which thrived for a long time in the plains of France’s
Alsace region. Since the 1960s, there has been a decline in the hamster
population, which is on the verge of extinction today.

And, at the same time, what we have seen is
an increase in the agricultural area where corn is cultivated. Caroline Habold
wondered whether the collapse of the population was linked to the sudden glut
of corn. So she did a laboratory experiment, feeding hamsters exclusively corn.
During breeding, we observed behavioral disturbances in females, which resulted
in hyper-aggression and hypersensitivity as soon as there was noise in the
room.

And above all, what we did not expect is
that these females would devour their young the first day after birth. This
behavior was observed in more than 80% of females. A dietary deficiency was
enough to make a hamster devour its children. The cause? A simple vitamin. A
lack of vitamin B3 is at the origin of this abnormal behavior. When we
supplemented them with vitamin B3 in addition to their corn-based diet, they
exhibited quite normal behavior.

What foods kill brain cells

They began to nurse their young, to raise
them in the same way as the females that were fed a diversified diet. The case
of the cannibalistic hamsters is disturbing. Could a unbalanced diet also trigger
aggressive, violent behavior in humans? Ap Zaalberg is a clinical psychologist
and political advisor to the Dutch Ministry of Justice. His specialty:
nutrition and crime. He is convinced that enriching food with vitamins, fatty
acids, and minerals can reduce aggression. It’s a hypothesis that is difficult
to test in normal life because so many factors and circumstances can influence
our behavior and our impulses.

In order to study nutrition without the
influence of the many parameters, he chose prisons as a nearly ideal setting.
Here in the Netherlands, we conducted a study of young prisoners in eight
different prisons. For three months, we gave them vitamins, minerals, and
fatty-acid supplements. And then we looked at the effect on their behavior.

We measured it in two different ways.
First, we asked the detainees how aggressive they were and we asked the
supervisors for their views on the issue. Above all, we looked at the incident
log. The number of times detainees were punished. And we saw that solitary
confinement had fallen dramatically. In the group of inmates whose meals were
improved, the number of incidents was reduced by one-third.

Is banana good for brain?

 

 What
we eat may have the power to change our moods, to stimulate certain impulses.
But could the food on our plate also influence our decisions? the ones we
believe we make using our free will? When people are asked if they think that
the food they eat has an impact on health, most of them answer “yes.” But
when asked if diet can also influence tthoughts and decisions, very few people
are willing to believe this is the case.

 However, at the Institute of Psychology of the
University of Lübeck in Germany, Professor Soyoung Park has, for the first
time, proven it. Her work reveals the mechanism by which food could influence
our thoughts. And for that, the researcher has developed a rather original
experiment. Imagine that you face the following dilemma. The money on the table
is to be divided into two sums. But it’s your partner, a stranger, who decides
how it is to be distributed. I‘ll give you two euros and keep eight for me. If
you accept the unfair offer, you leave with a little money but much less than
your partner’s. If you refuse, no one wins anything.

 So
what would you do? Do you accept the offer and take the two euros, even if you
feel cheated? Or, do you refuse, and leave with empty pockets but your head
held high? Well, it turns out, surprisingly, that whether you’ll take the money
or not depends on what you’ve just eaten. As part of this study, we follow 24
people who came to the laboratory twice to have two different breakfasts. We
found that the same person made completely different decisions based on what
they ate in the morning. To the test person, the two breakfasts look the same.
In reality, one is far more protein-rich than the other. The ratio of protein
to sugar is the only parameter that changes. A few hours after the meal, the
subject takes several tests on a computer. Today he tends to accept the offer.

His self-interest outweighs his anger at
the unfairness, and he will leave with a little money in his pocket. Last week
he mainly refused and won almost nothing. When the subjects consumed a
higher-protein breakfast in the morning, they were more tolerant towards unfair
offers. Conversely, when the subject had consumed a high-carbohydrate
breakfast, he was less tolerant in the face of unfair offers. On average the
subjects who had little protein rejected unfair offers twice as often. But how
can this surprising result be explained? In their search for biological
evidence for this observation, the scientists carried out blood tests.

 We
will send the blood to the lab right away and they will analyse the level of
hormones and amino acids in the blood, especially the hormones insulin,
cortisol, adrenaline, and A-C-T-H. And for the amino acids tryptophan and
tyrosine. Of these substances, the most important is tyrosine. The amino acid
is one building-block of a protein that is key to brain function: dopamine.
This molecule ensures communication between neurons involved in motivation and
risk-taking. The results of the blood analysis show that subjects with higher
levels of tyrosine in their blood are more willing to accept the unfair offer.
In other words, what we eat can within hours subtly alter the chemistry of the
brain, and thus the communication between the neurons. Enough to guide some of
our decisions. Experiments are continuing in Lübeck to confirm this result.

 The
implications are wide-ranging. Since we eat three times a day, every day, we
realize that food has enormous power, modifying and shaping us. So it’s
important to think about how we can use food to promote our well-being and
optimize our mental state. Not only does an unbalanced diet affect our brain
functions and behavior, and our meal plan interfere with everyday decisions, it
is also becoming increasingly clear that diet plays a decisive role in our
mood? and, possibly mental health. But what about junk food, dripping with
sugar and bad fats? What would happen if we ate more of that? This is the focus
of research here in Australia at the University of Sydney. Margaret Morris runs
a laboratory where rats are fed the kind of junk food that you find in
supermarkets or cheap, fast-food restaurants. Our experiments use a range of
Western foods, of the type eaten by all of us. So we feed ouf rats meat pies,
chips, cakes, and biscuits.

 The
sort of foods that are readily available and cheap. So we are modelling the
Western world. The first consequence of this diet: the rat doubles its food
rations. The animal seems never satiated. But that is not the most surprising
outcome. One of our chief interests is the impact of this diet on the animal’s
memory. And we can measure this easily in the rat by using a task known as the
novel object and novel place task. In this test, the researcher places objects
in the rat’s cage. The animal comes over immediately to examine them. Rodents
are very curious by nature. Once it has completed its examination and memorized
its surroundings, it is temporarily removed. We then place the animal in the
arena with one object that has been shifted.

foods that are bad for your brain and memory 

On its return, the rat spends more time
examining the object that has changed places because it already knows the other
objects. They are engraved in its memory. The rats stuffed full of bad foods
behave differently. What we observe is that animals eating a high fat diet or a
high sugar diet, or the combined high fat? high sugar foods, were less able to
recognise, to remember that that object had moved, they explore the two objects
about the same, that shows an impairment of spatial memory. The overfed rats
have not only damaged spatial memory, but also other malfunctions that sound a
warning signal for the scientists. They point to changes to the hippocampus, a
small region nestled in the center of the brain. It is essential for learning
and the consolidation of memory. Recent studies show that in humans a too
energy-rich diet also interferes with the hippocampus.

 We
see for example, that the quality of people’s diets is related to the size of
their hippocampus, to the size of their grey and white matter volume. And there
are starting to be intervention studies, so for example we see that only four
days on a junk food-type diet will have an impact on cognitive functions that
are related to the hippocampus. Margaret Morris is now seeking to understand
how sugary and fatty foods disrupt the brains of her rats to the point of
affecting their performance. She has a hypothesis, namely: Eating too much fat
and sugar triggers an inflammatory reaction that spreads to the neurons. So, in
response to these foods, there is a general inflammatory response all around
the body. This has been well described in obesity, but it now appears to be
quite an acute response as well.

 And
what we find is that inflammatory molecules such as cytokines are increased in
response to the diet. An overly rich diet confuses the immune system. It
reponds by triggering an inflammatory reaction, especially in fatty tissues.
Our fat masses release substances that then propagate this inflammation
throughout the body. Neurons were thought to be spared this effect behind the
protective blood-brain barrier, the semi-permeable membrane that separates the
circulating blood vessels from the brain. So there is increased inflammation in
the whole of the body, and we think this may spread to the brain.

 That’s because the blood-brain barrier which
normally protects the brain from inflammatory molecules may be impaired in fact
by the diet and become leaky, allowing traffic of molecules into the brain. The
inflammation infiltrates the meninges and then triggers a surprising
phenomenon. In her laboratory, Sophie Layé has shown in her overfed mice that
certain immune cells in the brain, the microglial cells, begin to devour
neurons.

How foods affect your brain

These microglial cells within the brain are
important because they can eat dead neurons. But when they are deregulated?
especially in a situation of unbalanced nutrition? they start to eat neurons
that are alive. Therefore, by consuming these neurons in excessive numbers,
eventually they will destroy or participate in the destruction of neural
networks. That includes neurons that are alive and that should be functional.
This reaction of the microglial cells could be filmed in-vitro. The images show
how energetically they move. The red objects are fragments of neurons that they
ingest. In an obese mouse, the activity becomes frenetic.

 This
phenomenon is suspected of significantly affecting the functioning of the
brain. We’ve been saying to people for 30 years, don’t eat these foods, you
might have a heart attack, you might get cancer and diabetes. It hasn’t worked
to change people’s behavior. We hope that if people understand that what they
put in their mouth is actually really essential to the health of their brain
and that of their children, that might have a more profound impact on people’s
dietary choices. Microscope, micromanipulator, and ultra-sensitive recorder:
Xavier Fioramonti is at the helm of an apparatus that can record the electrical
activity of a single neuron. The principle is simple, a slice of mouse brain is
immersed in a liquid that keeps it alive.

 The
researcher approaches it carefully with an electrode. It’s a meticulous
operation. Here, I lower the pipette into the slice of brain and now we will
approach this recording pipette near the neuron to make contact. That’s it,
we’ve made contact and now we will be able to measure the electrical activity
of the neuron. The upper peaks that we see are ares for potential action. This
is how neurons encode information. The time that elapses between the peaks is
the message sent by the neuron. Now we will raise the glucose concentration in
the bath.

foods that are good for your brain and memory

 

And we will see if this cell responds to
this increase in the concentration of glucose. As can be seen here, this cell
responds to the increase with more electrical activity. There is more potential
for action than we saw here before the increase in glucose concentration. This
signal comes from a single cell. But in the brain, the neurons are all
connected to each other. That makes the scientists suspect that glucose has the
ability to modify the activity of entire brain areas that control emotions and
pleasure. Is this how sugar ensures its grip on our will? This is, for the
moment, only a hypothesis. But today, sugar addiction is the subject of intense
research in laboratories. And what appears more and more clear is that the
power of sugar is similar to that of a drug. 

Serge Ahmed was one of the first to provide
proof with a very simple experiment. Step one, he raised rats, giving them
cocaine and sugar. Then after weeks of this diet, he presented the animals with
a choice. We have the situation in which the animal has the choice between a
lever that is connected to a syringe that contains a drug solution. And, the
drug in question is a hard drug like cocaine and heroin. And on the left, a
lever allows him to control a syringe that contains a sweet drink. And, there
we see that the animal chooses to take the sweet drink. The rats selected the
sugar water four times more often than the drugs. It can’t be called a glucose
overdose, but the irrepressible desire is plain to see. So this experiment
simply shows that sugar has more addictive potential than we had imagined and
it is, perhaps, even stronger than the pull of hard drugs, such as cocaine and
heroin. Today, we live in a food environment that is a little crazy.

 We
find sugar in a lot of foods, as we would expect, in sugary drinks. But we also
find sugar in foods that are not meant to be sweet, such as ham and soup. We
could cite other examples, but it is adding sugar to these foods that
contributes to the fact that we make people addicted to them without their
knowing it. Here at the Oregon Research Institute, the influence of sweet food
on the human brain is being investigated. What this program of research has
revealed is that habitual consumption of energy-dense food alters your neural
circuitry in exactly the same way as consumption of drugs of abuse.

Eric Stice recruited about a hundred
students, half of whom regularly eat ice cream, while the others never eat it.
They all came to the laboratory to drink a milkshake inside an MRI device and
give the researchers a peek into their brain activity. Great, Casey, so what
we’re going to do today is give you a chocolate milkshake and record the brain
activity in your entire brain, as you receive and anticipate receiving the
chocolate milkshake, to look at the neural basis of consuming energy-dense
foods. The test subjects can sip the milkshake through the tubes without moving
their heads. What we found out is that the people who never eat ice cream, you
could trace the reward circuitry? everything lit up just beautifully, and it
activated things very strongly, but in contrast the people who ate ice cream
every day showed a very diminished response, there was hardly any activation
whatsoever, illustrating that regular intake of an energy dense food really
reduces the pleasure you experience when you consume those foods. The reward
circuit is a region of the brain that controls the feeling of pleasure.

 It
is particularly responsive to sugar consumption. But eating too much ends up
weakening its responsiveness, so that at the same dose, the sensations of
pleasure are ultimately reduced. And Eric Stice’s experiment reveals another
more subtle, and perhaps more pernicious, effect. After a diet too rich in
sugar, the brain becomes hyper-sensitive to images of food.

 The
more and more you eat ice cream, the less and less the reward circuitry is
recruited when you consume ice-cream, but the more your reward circuitry is
activated when you see cues that say you might get ice cream. So your reward
circuitry fires up when you see an ice cream store as you’re driving down the
street, or you see a commercial for ice cream on the television, and the reward
circuitry activates much more for people who eat ice cream all the time than it
does for people who don’t. And that prompts eating in the absence of hunger
that drives obesity and weight gain.

This direct influence of food on our brain
plays a crucial role in what we choose to eat each day. What happens in the
brain at the moment we pick a dessert rather than an appetizer, or fish rather
than red meat? Who is really pulling the strings? Carlos Ribeiro and his team
are leading researchers on food choices. What we really want is to find all the
components, all the genes, the molecules, the neurons, which direct feeding
decisions, and for that we have to be able to look at very fine and small
effects. The simplicity of this animal model, the fly, makes it possible to
explore new avenues and new hypotheses. To understand the feeding behavior of
the fly, Carlos Ribeiro has developed a machine that monitors the insect’s
choices in great detail. When it’s touching the food, which is in the other
electrode with its tongue, the proboscis, then we can measure with the sensor
here, which is the same sensor which you use on your iPad or your iPhone to
detect touch on the screen. Just that here, we don’t detect the touch on
screen, we detect the touch of the food and so, we can really now dissect and
analyse the choice of the fly for protein or sugar.

  But
also when it is eating from the different foods, how it eats, how much it eats,
how fast it eats, and how often. We can really dissect all the details of the
decisions which are controlled by the brain. Thanks to this technique, he has
been able to prove that the main reason for choosing food is first of all
deficiencies. Naturally, flies that lack protein will choose protein-rich food.
But looking more closely, Ribeiro observed that this is not always the case.
But sometimes actually we had some flies which didn’t have this strong urge to
eat protein.

 And
then we were wondering why that was the case, and so when we looked, it turned
out that the flies which had no craving for protein had gut microbes. And so
following up on many experiments, we showed that there are two specific gut
microbes which, when they are in the fly, they suppress protein appetite, and
therefore these two microbes have a very important influence on protein
cravings in flies. Flies, when choosing their diet, are influenced by the
bacteria in their gut.

 This
unexpected discovery raises an important question. Does the human intestinal
flora, called the microbiome, also act on our brains? Do our gut bacteria play
a role in our food preferences? At University College Cork in Ireland, John
Cryan does pioneering research on the microbiome. He has been able to prove
that gut bacteria can influence certain behaviors in animals as well. When you
take microbes from highly anxious mice and transplant them to normal anxious
mice, they become much more anxious, and vice-versa.

 Even
when you take them from normal you can normalise the stress response and the
anxiety. Scientists now even consider the microbiome to be a kind of
intermediary, a link between food and the brain. The main factor that
influences the composition of microbes is the food we eat. Diet and the
diversity of the diet is really important from the moment we’re born until we
die, in shaping the composition of the microbes. So we’re beginning to realise
the importance of what we eat has on what’s in our microbes, and how that’s
influencing what’s going on in our brain.

 Our
well-being depends, in one way or another, on our microbiome. A diet that is
good for our mood is first and foremost a diet that is suitable for the
bacteria in our intestines. This has led to the idea of using food to pamper
the brain and maintain mental health.

 And
it is the famous Mediterranean diet that has the scientists excited. The
traditional Mediterranean diet is high in a diverse range of plant foods, so
lots of different leafy greens, and different colored vegetables, but also
fruits. Very importantly, legumes. So this is your beans, and lentils, and
chickpeas. Nuts and seeds, fish, and of course olive oil. Olive oil is a very
important component of the Mediterranean diet. And we think that that diversity
leads to more diversity in the gut microbiota. The microbiota that live in our
gut. And that diversity in the gut has been linked to good health outcomes. We
ran the first study last year where we recruited 67 people with major
depression, they received dietary support with a clinical dietician.

Now over a three-month period this trial
took place, and at the end of that when we measured their depression again, we
saw that the degree of change in their diet correlated with the degree of
change in their depression. So, the more they moved towards a Mediterranean
diet, the more their depression improved. Using diet to serve the brain? it ‘s
an idea that’s catching on. Scientists are now exploring all kinds of clues.

 Spices used for centuries in traditional
Indian medicine are now being studied in labs for their benefits for mental
health. Red fruits and berries have awakened high expectations. The polyphenols
they contain might be able to rejuvenate neurons on the decline. Are red fruits
and spices the miracle ingredients for eternally young neurons? It is still too
early to say for sure. Researchers are only just beginning to uncover the
secrets of the remarkable relationship between nutrition and the brain. The
ideal menu for our little grey cells is still largely unknown.

 But
a balanced, diverse diet which does without processed food and sugar, and
favors fruits and vegetables, seems so far to be the best recipe for preserving
the mental faculties. My grandmother said “You are what you eat, so eat well.”
And what we’re realizing is that science is beginning to understand how true
she was.

If we limited the deficiencies, would that
reduce crime? Too early to say. What we do know is that when you bet on healthy
eating, it has effects on behavior. The more we over-eat Snickers bars, we
become hyper-vigilant to Snickers cues, and we eat a lot of Snickers. And we
create that monster in ourselves. So the best thing to do if you have kids is
feed them healthy foods and not get them used to eating this kind of crap.