Transcriber: Nikki Catt
Reviewer: Zsófia Herczeg If you ask elder people
what they're worried about, it's not about the economy, it's not even about coronavirus. Of course, we are worried about that. They're worried about dementia. It's the number one thing
they're worried about. Dementia affects something like
50 million people around the world. In Australia, 450,000 people. By 2050, there'll be 115 million people
in the world with dementia. In Australia, over a million people. Right now, we spend
one trillion dollars around the world and 14 billion dollars
in Australia on dementia. It can affect anybody. It can affect movie stars,
politicians, people on television, the wife of a former prime minister. It affected this woman. Her name is Auguste Deter. When she was 51, she was admitted
into a psychiatric hospital in Germany. The superintendent
was Dr. Alois Alzheimer. She died at 55. He did a postmortem. He took her brain. He sliced it. He applied the new stains of the day, and drew pictures
of the plaques and tangles which are now the hallmark
of Alzheimer's disease. People get confused: What's dementia? What's Alzheimer's? Dementia is an umbrella term. It's a loss of
thinking functions and memory which interfere with day-to-day life. There are over 100 causes. Alzheimer's is the most common. Problems with circulation in the brain, small strokes or big strokes and Lewy body and frontotemporal are the other big degenerative causes. It's usually progressive. It's usually untreatable. As I said, it can affect anyone:
it's a very democratic disorder. It's not always untreatable. Alan Bond lost his memory, but when he came
out of jail, he was cured. (Laughter) Okay. As reported in the Sydney Morning Herald, Lenny McPherson came to see me because he wanted a diagnosis of dementia
to reduce his sentence. I was terrified because I couldn't give him
that diagnosis. Dementia affects all races
in all countries. Sadly, in Australia, aboriginal people
have a much higher rate of dementia, at least double. And it comes on earlier. And this may be a common theme because two-thirds of the world's
population with dementia live in the developing world, where there is often issues
with poor antenatal and perinatal care, poor socioeconomic circumstances, lack of education and not good nutrition. And these are all things
we should do something about. Education in early childhood
may be one of the most preventative things that we can do. So can we prevent dementia? Can we prevent that brain on your left becoming the brain on your right? The one on the left weighs 1.3 kilograms. That's the one in our skull here. It's got fluid, it's got protein, it's got fat. And it's an amazing organ - as Woody Allen said,
"my second most favorite organ." (Laughter) But in Alzheimer's disease,
it shrinks to half that size, to 650 grams. So these are the things
we need to think about: physical inactivity,
high blood pressure in midlife, type 2 diabetes, smoking,
and obesity in midlife. These are things
we can all do something about. It's never too late; it's never too early. So exercise. Exercise is good for us. I'm a big fan. It's good for our muscles;
it's good for our bones. It's good for our heart;
it's good for our blood pressure. It's good for our mood,
for our feeling of well-being. For some cancers, it helps with recovery. And it's also good for our brains. Yes, good for our brains. People who exercise more
have less dementia when followed up 10 or longer years later. It can be aerobic exercise, like running or walking or swimming, or anaerobic - resistance training,
pulling pulleys or weights. What about brain training,
exercising your brain? Does sudoku or crosswords do it? Maybe not unless
it's David Astle's crosswords (Laughter) because they're so hard. But you need to stretch the brain. So it could be learning
a musical instrument or learning a language. But what's really taken off
is brain training programs. There are oodles
of computer training programs making lots of money
and showing benefits - not just on the computer program,
but actually generalizing, and with boosters,
may be able to be maintained. So this is a growth industry. Obesity, the curious paradox. People who are overweight
or obese in midlife have a higher rate of dementia
10, 15 years later. But the people who get past the age of 75 and are obese may even have some protection. Is this a survival effect? Those who get there
must have some special resilience. Can you eat your way to brain health? [Mind your diet] It would be great if you could. Most of the evidence
is for the Mediterranean diet, and what that is is lots of plants, plant food - vegetables, fruits,
nuts, legumes, grains - with smaller amounts
of fish and other seafood and the smaller amounts
of poultry, eggs and cheese and much less in the way
of red meats and sweets. Less than 1/3 of our diet should be fat and less than 8% saturated fats. The jury is out about alcohol. It may have some beneficial effects,
but it may also not. And there may be
an increased risk of cancer. So what if you don't want to do all that? You want to just take the supplements,
go into your chemist. I go to the chemist,
I see on the counter "brain food." That's something like brahmi
or Ginkgo biloba or whatever. Most of these have no evidence. They may help. We just don't know. The ginkgo - there have been
two large studies, France and US: negative - no difference to the placebo. So it's better to eat your fish
than to take omega-3 supplements. Hearing. There's been an association between people who have
hearing loss and dementia after 17 years later. Doesn't mean all people
with hearing loss get dementia or people with dementia
have hearing loss. It's an association. The good news is that recent studies have shown that wearing hearing aids
may mitigate that risk. And one of the mechanisms, putative, is that people who lose their hearing
become more socially withdrawn, because it's showing evidence
that people who are less socially active, who don't come to TEDx talks, who don't mix with friends and families are more likely to have dementia
when followed up over a decade later. People who are more actively engaged
have less dementia. So putting all of this together - 30% of the risk
of Alzheimer's in particular can be accounted for
by environmental factors that you and me, we all can do
something about, right now. Can we eradicate it? You know, we've eradicated
smallpox from the planet with a vaccine. This is Jenner giving the first vaccine. There are plenty of trials now being used, using vaccines against
Alzheimer's disease. They have not yet succeeded. There are many drug trials
happening right now. Pharma, Big Pharma, is investing
billions of dollars in these trials, so far without success. Our best bet might be lifestyle changes. Now, we're doing a trial,
"Maintain Your Brain," all on the internet, to try and encourage people and coach them into eating well, exercising,
brain training, etc. So can we prevent Alzheimer's
and other dementias? No. But we might be able to delay its onset. And this is really important because if we just delay it
by a couple of years, there would be 20% fewer people
on earth with dementia. If we can delay it by 5 years, 50%. Well, how does that work? It works because dementia
is a disease of late life, by and large, not always. And so if we could push it back,
ideally till after we die, (Laughter) we'd be fine. So we need to be the change. We need to embrace
these things and do them. We can do them now. This needs to be at the individual level. It needs to be at the medical level. And it needs to be at a population level
and with government policy. Thank you.
