Translator: Rhonda Jacobs
Reviewer: Tanya Cushman Hi everybody. I want to begin with a quick
little exercise if you will indulge me. I want you all to close your eyes - don't worry, this is not
going to be a meditation - just close your eyes for a few seconds. And I want you to picture
somebody that has dementia. Okay, what does the term
"dementia" evoke for you? Maybe you have a relative
with the disease. Maybe you've seen a documentary recently. There's no right or wrong answer. Just get that image in your mind's eye. Now I want you to open your eyes,
and if the image you had in your head looks something like the person you see
on the screen in front of you, I want you to raise your hand. Alright, that's quite a bit of people. Now I want you to raise your hand
if the image you had in your head looks somebody like the person
that you see on screen now. Okay. Much less people. This is my mother. And her name is Kathy,
and she has dementia, and I love her very much. And when I had to come
to terms with the fact that my mom was showing
the initial signs of memory loss in her 50s a couple of years ago, it was an incredibly traumatic
experience for me, and it's still, to this day,
incredibly heartbreaking to have to acknowledge. But because I couldn't chalk up
what I was seeing in my mom to typical aging - clearly she's not the picture of a person
succumbing to the ravages of time - I decided to learn
all that I possibly could about the ways diet and lifestyle
mediate risk for neurological disease, brain health, and ultimately
brain function itself. Now, what I learned shook me to my core. You see, I thought, like you guys,
that dementia was an old person's disease. You see, not only is dementia
not a normal aspect of aging, but it begins in the brain decades
before the first symptom of memory loss. If you make it to the age of 85,
you have a one in two chance of being diagnosed
with Alzheimer's disease. That's 50 percent;
those odds are not very good. And unfortunately
for my generation, millennials, we're the first generation in history
that's going to reach the age of 90, according to the Stanford
Center on Longevity. Now, I think I speak for many millennials when I say that generally
we believe science has our back, right? Ninety is a long ways from now. By the time I get to that age, we're going to have
some kind of pharmaceutical cure - ultimately, not something
I have to worry about. Well, unfortunately, Alzheimer's drug trials
have a near 100 percent failure rate. Let that figure sink in, okay? That's worse than the failure rate
for cancer drugs. I mean, those are dismal statistics. Therefore, unless
we can prevent this disease, one in two millennials will have it,
which is pretty heartbreaking. For the past century, the conversation surrounding
Alzheimer's disease, the most common form of dementia,
has been one dominated by doom and gloom. That's because since 1906, when Alzheimer's disease
was first coined and named by the physician Alois Alzheimer, 90 percent of what
we know about the disease has been discovered
only in the past 15 years. So that is to say, this is
a rapidly evolving field of science. And while we don't yet
have all the answers - there's still no cure;
I wish we had a cure - we do have enough information
to say that today, for a significant proportion of people,
it is a potentially preventable disease. Here we have a statement written in 2014 by 109 leading scientists
and clinicians around the globe stating very plainly that in 2014,
we had enough evidence to say that dementia and Alzheimer's disease
is a preventable disease. And just this year, for the first time, at the Alzheimer's Association's
International Conference, it was acknowledged that one third
of dementia cases may be preventable. Depending on what literature you review,
even more may be preventable as well. This is just the statistic
that was most recently published in the journal Lancet, which is one of the top
medical journals in the world. And here we have coverage
from that same event alluding to the notion that a field is now looking for hope
in an area once thought impossible. Now, when it comes
to our diets and our lifestyles, and their impact on our health, it's been said that our genes load the gun
while our choices pull the trigger. So I became obsessed with trying to understand
what it is about the modern world that makes it so likely
for our choices to pull the trigger on diseases like Alzheimer's disease. So I did a deep dive into the literature. And I looked at parts of the world,
like in Ibadan, Nigeria, home of the Yoruba people. Now, there, the most common and most well-defined
Alzheimer's disease risk gene, that in the United States puts somebody at anywhere between a 2- and 14-fold
increased risk for developing the disease, there, has little to no association
with Alzheimer's disease. So in other words,
if you live in the United States, and you are genetically at risk
for developing Alzheimer's disease, you might move to Ibadan, Nigeria,
and see that risk disappear. So I started thinking
a lot about evolution and the kinds of diets
that our ancestors might have consumed during the time
in which our brains evolved - the magnificent supercomputer
that each one of us is heir to, this incredible legacy - and I realized that for two million years, our ancestors ate in a way
that led to the evolution of our brains. That's pretty amazing. But then, 10,000 years ago,
something happened. We turned our backs on that diet. We went from being hunter-gatherers,
eating according to seasonal availability, the world was our buffet, we got our nutrients
from the 50,000 edible plant species that there are around the world, and we became settlers, essentially becoming slaves to the few crops
that we could domesticate. Over time, our brains lost the volumetric
equivalent of a tennis ball. So let me just rephrase that
so you really get it. We ate a certain way for two million years
that led to the evolution of our brains, then we turned our backs on that diet. This ultimately paved the way
for the fact that today, 60 percent of the calories
that we consume worldwide come from three plants. Three plants. Wheat, corn, and rice. Perhaps even worse, 50 years ago, these crops became the basis
of our dietary guidelines, where for the first time in human history,
human beings were told how to eat. We were told to base our diets
on healthy whole grains. I mean, I grew up, the Food Pyramid -
which is now debunked - existed, telling me that if I wanted to be healthy, I needed to load up on anywhere
between 6-11 servings of grains per day. And today, the advice is still given that to be healthy, we need
to incorporate grains in every meal. Well, when we look at research, like what was recently
published by Cochrane, which is an organization that has a partnership
with the World Health Organization and is known for their unbiased,
systematic reviews of medical research, we see that there is no evidence
to suggest that eating grains, including whole grains, improve our health. Now, in this research review,
they looked at a certain kind of a trial: they looked at a randomized
controlled trial. Now, randomized controlled trials are the only kinds of trials
that can show cause and effect, which is why this research
is so important. But perhaps the most insidious thing
about these three grains is that today they're pulverized
and packaged and sold to us in processed foods
that line our supermarket aisles. These ultraprocessed foods now make up 60 percent of the calories
that we consume worldwide. When we consume
these exact kinds of foods, they set off the equivalent
of a forest fire in the body. And the brain sits
directly downwind of that fire. That fire that I'm talking about,
that's called inflammation. And inflammation directly
accelerates brain aging and worsens pre-existing disease states. Now, our bodies have an incredible
capacity to heal from inflammation. That's what's so great
about being a biological entity. Our bodies are so smart. But the problem is our bodies
need the proper ingredients to be able to repair from inflammation. Unfortunately today, 90 percent of Americans are now deficient
in at least one vitamin or mineral. Why do you think that is? Well, that's because
we're basing our diets around not only
these ultra-processed foods, but processed foods
made from these three crops, which are pretty scarce
when it comes to nutrients. They're calorically dense, but they are not nutrient dense,
which is a key differentiator. Another thing that
these foods do very well is they send levels
of blood sugar through the roof. And when blood sugar is elevated, an ancestral hormone in our bodies
also becomes elevated. That hormone is called insulin, and insulin is the body's
chief fat-storage hormone. The fact that we're relying
so much on these kinds of foods is why for the first time in history, there are more overweight people
walking the earth than underweight. Now, the other thing
that insulin does really well is it turns your fat cells into the equivalent of a subway turnstile
in midtown Manhattan during rush hour. Basically, calories can flow
into your fat cells, but they can't come out. Now, this is very problematic because there are certain
organs in our body that have evolved to use fat, and use it remarkably well -
in particular, the brain. The brain loves to use fat for fuel. In fact, I call fat
our body's birthright fuel. You see, when we're born, human babies come packaged
with an unusual amount of fat. Our fatness rivals that
of baby seals, actually. We come packaged with a really
high percentage of body fat. I don't mean to make
any babies in the audience insecure. If there are any babies
in the audience, I apologize, but it's actually fascinating why it's believed we come
packaged with so much fat. You see, the human baby is born
with a half-baked brain. We complete our development in the world. This is often referred to
as the fourth trimester. If we were born cognitively with the skills that some
of our simian ancestors are born with, our gestation would be twice as long. This is one of the reasons
human beings are so smart. We complete our development in the world. And it's thought the fat
that we come packaged with serves as a sort of Mophie
for the developing brain. The developing brain
is incredibly energy hungry too. This is why that's so useful. The newborn brain uses 90 percent
of the baby's metabolic rate. So that means that 90 percent of the oxygen and calories
that the baby is consuming goes to fuel its brain. But the baby couldn't possibly consume
enough calories to support that, therefore, fat. In the human adult brain, the ability
to use fat for fuel is not lost. In fact, as adults,
our brains still love to use fat. It could almost be said - almost - that when the brain
is using fat for fuel, it's not aging. And the fact that we constantly,
chronically deny the ability of the brain to use fat for fuel due to our chronically
high-carbohydrate diets, well, this might be one of the most
detrimental aspects of the modern diet. And this could, partly,
explain why it's thought that 40 percent of Alzheimer's cases may be attributable
to chronically elevated insulin alone. Again, insulin is the hormone that turns our cells
into that subway turnstile. And this was a figure published
in the Journal of Alzheimer's Disease, which is one of the leading
dementia journals worldwide. So knowing what I know about the brain
and how to properly feed it, I've become obsessed
with what I like to describe as resetting my brain
to its factory settings. So I like to spend more time with my body
and brain in a low insulin state. And the quickest way,
the best and most efficient way, of getting your body and brain
into a low insulin state is via fasting. Luckily, we all fast every single day. This is when we're asleep. So what I like to do
is I like to pad my sleep by two or three hours on each side with an additional time frame
in which I'm not eating. A lot of people call this
intermittent fasting. But essentially, one of the main goals
of intermittent fasting is to allow your body and brain
to spend more time in a low insulin state. When it's time for me to eat,
I opt for nutrient density, which describes foods that have a very high ratio
of nutrients to calories. And there's no better example of that than dark, leafy greens,
like kale and spinach. They have tons of nutrients
that protect your brain cells and help your brain cells create energy, and they have very few calories. In fact, the consumption
of dark, leafy greens is associated with reduced aging
by up to 11 years. I eat lots of eggs. You see, I learned
that when an embryo is developing, the first structure to develop
is the nervous system, which includes the brain. Therefore, an egg yolk
is literally designed by nature to contain all
of the necessary ingredients required to grow a healthy brain. I also eat two to three servings of humanely-raised
grassfed red meat per week. If I was a pre-menopausal woman,
I would probably eat three to four because red meat contains an abundance
of highly bioavailable micronutrients. And in fact, a lot of people today say that there's no place for meat
in a healthy diet. But to that, I invoke a quote
from one of my heroes, Carl Sagan, who said that extraordinary claims
require extraordinary evidence. And researchers believe that it's not just access to meat,
but cooked meat that catalyzed the growth
of our brains during our evolution. I eat lots of fatty fish: salmon, wild salmon, and sardines. And this is actually my perfect plate. It's half, if not more,
filled with colorful, fibrous vegetables and a piece of protein
that's not just protein. It's got a ton
of essential micronutrients, like DHA fat, which is one of the most important
structural building blocks of the brain. We now know that the adult brain
can grow new brain cells up until death. But the impetus there is
that we need to supply our brains with the appropriate
building blocks to do so. I also eat tons of fruit. But not all fruits, okay? I eat lots of avocados. Avocados have the highest percentage
of fat-protecting antioxidants of any fruit or vegetable. This is really important
and really key for brain health because your brain is constructed of fat. Sixty percent of the brain
by weight is fat, but it's a kind of fat
that is highly vulnerable and prone to oxidation. We need to supply our bodies
with fat-soluble antioxidants like vitamin E - I eat lots of avocados, an avocado a day. And I avoid, for the most part,
modern, cultivated sweet fruit. I'm not going to stand up here, guys, and tell you that the banana
on the right is toxic. It's not toxic! But today, our modern fruits are bred
to contain more starch and sugar than ever before in history
because we like the way it tastes. Compare the modern banana
to the wild banana on the left, and you'll see the contrast is stark. And the research on fruit, okay,
might surprise you. Published in the Journal
of the Alzheimer's Association, it was found when looking
at older adults that higher fruit consumption was
associated with shrinkage of the cortex, which is your brain's grey matter. Now, researchers in this journal wrote - they compared that eating foods
with high glycemic load, whether as fruit
or highly refined carbohydrates, may have the same
detrimental effect on the brain. Now, this research is really fascinating because fruit is usually associated
with an overall healthy dietary pattern, but rather than just looking
at diets as a whole in this research, they looked at individual
dietary components as well, where they came to this finding,
which is very striking. I also consume lots of fruit juice, but only one kind of fruit juice: extra virgin olive oil,
which is actually a fruit juice. Extra virgin olive oil is a staple
of the Mediterranean diet. It's one of the main features
of the Mediterranean diet, adherence to which is associated
with a robust risk reduction for Alzheimer's disease and dementia. No talk about preventing
dementia and cognitive decline, which is the most important topic
I think there is, would be complete without
a little bit of a chat on exercise. So aerobic exercise is really important. I don't do my aerobic exercise in the gym,
I do it in the real world. I try to imbue my day
with as much movement as possible. I'm always walking, I take the stairs
whenever given the opportunity, and I bike-ride whenever I can. I know you guys in Venice
love bike-riding. The best thing about aerobic exercise is that it boosts something
called BDNF in the brain. Remember this acronym;
it's very important. Brain-derived neurotrophic factor. It's a guardian protein. It's a guardian molecule that not only ensures the survival
of your existing neurons, but promotes the growth
of new ones as well. It's key for neuroplasticity. And aerobic exercise
is the best way to stimulate BDNF. I also love to lift weights. Aside from making me
look better naked, which it does, having stronger muscles is really important
for brain function and brain health. Why? Because the same exact stimulus
required to grow your muscles and make them stronger also acts on your brain cells
to make them more efficient. So where is the research to show that making all of these changes
in your lifestyles and diets is going to be worth your time? Where's the hard data? Right? Well, to answer that question,
I refer to the incredible FINGER study, which was led by Dr. Miia Kivipelto at the Karolinska Institute
in Stockholm, Sweden. I had the pleasure of visiting
the Karolinska Institute and interviewing Miia Kivipelto, and what's so great about the FINGER trial is that it's the world's first-ever
large population, long-term, randomized controlled trial. Randomized controlled trials, remember,
are the kinds of trials required to prove cause and effect. And what she found
in this incredible trial was that in her older adult
at-risk population, that by adhering to a battery
of dietary and lifestyle interventions, many of which I've described already, she was able to improve executive function
in her subjects by 83 percent and improve processing speed
by 150 percent. Now, this is incredible, and it's also particularly poignant for me
in regards to executive function because my whole life
I've struggled with executive function. Here's a letter written
by my guidance counselors in elementary school,
in the days before e-mail, to my parents suggesting that I see a psychologist
because I had a lot of trouble focusing my attention
and tuning out distraction. And that's why all throughout
my academic career, my grades were never good. That's why I went into film
instead of going to med school, which is actually
what I really wanted to do. If only I knew then what I know now. So in closing, thanks to research
performed by AARP, we know that brain health is important
to 93 percent of Americans. That is awesome. What's less awesome
is that very few people know how to maintain
or improve brain health. So I'm trying to fill
this knowledge gap for people. Because every three seconds
a new dementia case is diagnosed. Let that sink in. I mean, that's, like, heartbreaking. In fact, since I began
speaking to you guys, 400 people around the world
were diagnosed with dementia. But for me, this is not about statistics. This is about a person
who I love very much: my mother. And truthfully, I would do anything
that I could to get her back into the state she was before the monster
that is dementia took over. But it's made me incredibly passionate
about spreading this message of prevention out to people of all ages. Our cognitive health
might be a choice that we make with every bite that we take. And I want to be very clear
that there's no person walking the earth who's not at risk. The brain is highly delicate and vulnerable to the many insults
thrown at it by the modern world. You're never too young or too old
to make a brain-healthy choice. And our brains really make possible all that it is that we love
to do in the world. So for that reason, I hope
that you'll all agree with me when I say that it's worth protecting. Thank you. (Applause)
