- Hi, I'm Dr. Morgan Levine.
I'm a professor who specializes in the biology of aging.
Today, I'll be answering your questions from Twitter.
This is "Aging Support."
[upbeat music]
First up @bamabrat74,
"Why does the aging process have to be so dang painful?"
Over our lifespans,
we have a lot of biological and molecular changes
that accumulate in our bodies,
and ultimately, this makes our bodies function less ideally,
and causes a lot of these manifestations
we see with the aging, the aches, the pains,
the chronic diseases.
However, in aging science,
we actually think that we can disentangle chronological time
from biological aging.
So chronological age is what it says
on your driver's license.
However, this is different from what we call biological age,
which is really measuring the state of the organism.
We might say that even though you're chronologically
50 years old,
you have a biological state that actually resembles someone
who's more like a 60 year old.
And what that means is we can actually slow the rate
at which these changes accumulate,
or maybe even reverse them
and go back to a better functioning state.
And with that, we would actually give people
more years of life without the painful parts of aging.
All right, next up from @wildchild,
beep "My head hurts so bad hahahah,
why are hangovers getting worse as we age?"
Science doesn't have an answer for this,
and actually, a lot of scientists think that
it's just that you have poor recall
of what your hangovers used to be.
And actually, there is no evidence that hangovers get worse
necessarily as we age,
and you might just be forgetting how bad they were
when you were younger.
This could also be in terms of childbirth,
why women might actually be more willing to have a kid again
because they don't remember how shitty it was
to give birth the first time.
Next up, Jihane asks, "Why do we age?
Why do we grow old and die?
And how does the world really work?"
This is a fundamental question in biology.
I think of it as up there with what is life,
it's actually why I got really interested in this field
as a whole.
So an aging system is what we call a very complex system,
you have to have all your molecules and cells
in a very particular pattern to support aging.
So almost I like to use the analogy of the sand art,
you can lay out these different things
in a very specific manner.
And when it comes to life,
if you don't have that exact pattern, you don't have life.
The problem is that it's hard to maintain this.
So with any biochemical reaction that your body undergoes,
you can get a slight shift,
and over time, these accumulate in your system,
and we think that these are why you're manifesting is aging,
because you develop a state that is less compatible
with life than you originally had.
Next up, Eleanor Sheekey asked,
"How much of aging is genetic?
Is longevity heritable?"
The good news is, it isn't that heritable,
we actually that only about 10 to maybe 20% of your lifespan
is dictated by your genes.
And this is good news 'cause it actually means
we have a lot more control over how fast we're aging.
All right, next up a question from @MegSugaPop,
"Can the aging process stop?"
The science doesn't say that it can't happen,
but we're not close to doing this.
We are closed to showing that we can slow the aging process.
There is even some evidence that we can reverse aging
in some degree, especially in cells,
you can take cells from someone who is,
let's say 65 years old, and convert them back
to a cell that actually looks like an embryonic stem cell.
So we do think we have some power to change aging,
but to take an entire person stop the aging process
all together and hold them frozen at that age forever,
I think is probably a little farfetched.
@katrinadrcelic ask,
"Tell me then without saying anything misogynistic,
how do men and women age differently?"
Even though we might not be doing quite as well
in terms of the pay gap,
we're actually doing better than men
in terms of the longevity gap.
Women tend to live about four and a half years longer
than men when you look at the world population.
And even more than that, if we look at centenarians,
so these are people who live to at least age a hundred,
women make up 83% of that population.
But unfortunately, it's actually not all good news,
so there are definitely sex differences
in terms of kind of how we age.
So women tend to be much more at risk
for things like frailty
and for diseases like Alzheimer's disease and osteoporosis.
So even though we might live longer,
we do tend to suffer more for some of these debilitating
conditions.
So next up from @jayhans_3,
"I've plant-based for a minute,
but last week, I ate meat and I feel my absolute best
right now, like how and why?
LOL.
What is the secret to longevity?
Laughing my ass off."
Actually, longevity science says plant-based diet
is probably the best diet.
There's a lot of evidence from both epidemiological,
which is the science when you actually look at populations,
as well as some more emerging clinical trials,
that suggests that a diet rich in mostly plant-based foods
can actually extend your lifespan and prevent disease.
Next up from Subita Rahman,
"What are the barriers to figuring out biomarkers
or hallmarks to aging?
Is it that no one else has focused in on it too much
or lack of funding and people believing in it?"
I feel a little hurt by this question
because this is what I work on,
and I work really hard on it,
so I don't think this is just for lack of effort,
but this is actually a really complex,
difficult thing to figure out.
In terms of actually developing biomarkers of aging
or hallmarks of aging,
we have to first be able to actually measure these changes,
which is hard in and of itself.
But even after we can measure it,
we have tons and tons of data,
imagine millions or billions of variables
that we can actually have to put together
to identify patterns.
So this isn't just some easy feat
that, oh, you just need to look in a cell
and figure out what happens with age
because aging processes so multifactorial,
so many things happen.
We actually have to use a lot of computer science
and machine learning coupled with molecular biology
to really figure out not just what's going on,
but what things are actually causing
or driving the aging process.
From Pretty Matty,
"Does the aging process slow down in space?
Asking for a friend..."
There was a twin study with actually the Kelly twins
who actually looked when one stayed on earth
and one went to space,
what happened to them in comparison to their aging?
And unfortunately, they actually found that going into space
seemed to accelerate a lot of these hallmarks of aging,
or things that we associate with the aging process.
So we know that there's gravitational time dilation,
so actually, it would slow down the closer you are to earth,
but there's also time dilation
in terms of the speed at which you're traveling.
So if you're traveling faster,
time slows down, it's kind of counterbalance.
So it's hard to say, depends on what you're doing in space.
KenekEdge asked, "Is health span like lifespan?"
Most of us know what lifespan is,
it's basically how long you're alive.
But a lot of people haven't heard this term, health span.
And really what we use the term house span to mean
is the amount of time you're alive without disease,
or without some age-related functional impairment.
So even though health span and lifespan are linked,
we think if you can extend your health span,
you'll probably also live longer.
They are actually two different things,
and health span is more the part we care about.
We don't all want to just have more and more years
in a kind of more debilitated disease state,
we wanna have more healthy years,
so this is the part that aging research is trying to target.
Next up, we have a question from Amy Harmon,
"Science-y people, have there been some definitive debunking
and or validation of 'blue zones'?
Do centenarians in fact cluster there or no?
So for those of you who don't know,
blue zones are these places throughout the world
where they tend to have an enrichment
of people who survive to age a hundred,
they tend to be like longevity hotspots.
There have not been debunking of blue zones,
statistics don't lie.
Longer live people do live in these places,
but the reason that they're longer lived is still debatable.
So a lot of people speculate that they have really good,
healthy lifestyles,
they tend to be people who eat more plant-based diet,
have really active lifestyles and less stress.
But again, this is from looking at populations,
these aren't randomized controlled trials
where we pick a set of people,
we make them live in these places
and we see how long they live.
Next up from @carly_solstice,
"Does the aging process just go to warp speed
as approach 40?
I feel like my gray hairs have quadrupled
and my wrinkles madly increase in just the last few months."
What we see in the aging process
does seem to increase exponentially later in life.
Things like graying of hair, wrinkles,
the onset of different diseases,
but actually what's underlying that
in the biological aging process,
all these molecular and cellular changes
that we think are actually the root causes
of those manifestations happen much earlier in life.
However, it takes time for those to accumulate
before we actually see them on our skin, in our hair
or feel them in our bodies.
And that's why it actually feels like the aging process
is really accelerating towards the end of life,
but actually a lot of the changes happen much earlier.
Next up, we have a question from Sairira,
"Is aging a disease?"
My view on it is that, I don't like the definition
of disease.
When we think of chronic disease,
things like diabetes or heart disease,
these are not binary states, you have it, or you don't.
These are continuous processes,
they are things that lie on a continuum,
you can be more sick or less sick.
And actually, rather than saying aging is disease,
I would argue that most of these chronic diseases
are just manifestations of aging,
so I would actually flip it around.
So next up from @kaiser9798,
"I'm getting old, why do all my joints hurt now?
I didn't do nothing to warrant the pain."
So unfortunately, Kaiser,
this is something that's gonna happen to all of us,
we're all constantly getting older, we're all aging.
There are various reasons why your joints
might start hurting with age,
so you can actually lose some of the lubrication
between joints.
People can also develop things called osteoarthritis,
where you actually lose cartilage
and you have more kind of bone on bone.
We also lose strength in terms of our ligaments and tendons
and muscles that just make everything kind of not work
as well and start aching over time.
So next up, we have a question from Natali Marmion,
"Is 45, the new 35?
when it comes to pregnancy,
how safe is it to have a baby later in life?"
People alive today basically look like people from the past
who are only two and a half years younger,
so we're looking better,
but maybe not a whole decade better,
so you could say 45 is the new 42 and a half.
For the second question when it comes to pregnancy,
how safe is it to have a baby later in life?
The answer is, it probably depends on you.
The oldest woman to ever give birth,
I believe was just shy of 66 years old.
So for her, she was able to give birth to a healthy baby
and there was no issues.
However, we don't all age at the same rate
and some of us are able to reproduce much later in life,
and some of us are going to age faster and it's not healthy.
So ultimately, it's probably up to you
and your doctor to figure out what's best for you.
So next up, we have a question from Denis Wirtz,
"Cellular hallmarks of aging,
what are the most predictive determinants of aging,
the biochemical properties of cells
or biophysical ones?
For that, I would argue that actually the hallmark
that I study, epigenetic modifications
is probably the most predictive as of right now.
So what I mean by that is these are biochemical
modifications to your genome,
so one might say, okay, their biochemical properties,
but actually, they changed the biophysical structure
of your DNA.
So I don't actually think we can group things
into either biochemical or biophysical,
because in biology, we learn form equals function,
so the physical structure
will affect the biochemical functioning
of a lot of these molecules.
Next up a question from @57thSnowflake,
"Are you aware of any studies on epigenetics
and the impact on longevity,
and if so, what impacts have been seen?"
Yes, I'm aware of these,
these are actually what my lab focuses on
day in and day out, we studied the epigenetics of aging.
So what I mean by that is the epigenetics are changes,
so these are chemical modifications to the DNA
without changing the sequence.
And the exciting thing about epigenetics
is even though every cell in your body
has essentially the same DNA,
you're at the genetics is what gives cells their identity,
it's what makes a skin cell different from a brain cell.
The interesting thing is,
it also is what makes a young cell
different from an old cell.
So we actually see specific epigenetic changes,
so these chemical changes that occur as a function of age,
we can measure them and we can actually use that information
to infer something about how quickly someone to aging,
and this tells us something about the probability
that they're gonna die in the next 10 or 20 years,
and also the probability that they're gonna develop
various chronic diseases of aging.
So next up from Stormy Leather, New York,
"Are there any anti-aging remedies for hands?
'Cause that's what's aging on me the fastest,
my hands look 80!"
Probably not, I would recommend sunscreen.
Next up, question from @HeickShannon,
"What is senescence?"
This is actually the term people used to use
instead of aging, so we called it senescence.
More recently, people have actually started to study
something called cellular senescence.
And what cellular senescence is,
is when a cell undergoes some stress
or has reached the end of its lifespan,
it'll actually transition to what we call a senescent cell,
which means it's no longer dividing,
but you can't kill it,
so it doesn't have this, what we call apoptosis
or this selective cell suicide.
But the issue is that these cells accumulate in our bodies
as we age, and they actually have a really damaging profile,
so they're excreting all of these pro-inflammatory factors
that can damage the nearby cells
and cause a lot of tissue inflammation.
And so people in the aging field
have actually been trying to target senescent cells
to try and remove them from aging tissues,
thinking that this'll restore some anti-aging benefits.
So next up from @ethanjweiss,
"Is it true that calorie restriction does,
while exercise does not increase lifespan in mice?
If so, why?
And is that interesting?"
Well, actually there's evidence now
looking at different mouse strains,
so these are mice with different genetic backgrounds,
that actually showing calorie restriction
doesn't work quite as well in all of them.
In some of them, they actually live shorter
when they restrict their calories.
In terms of exercise,
I actually don't think that there's good evidence
that exercise is not beneficial.
There was a study that showed
that there was a very limited increase in lifespan
for the exercised mice versus sedentary mice.
But the important thing in that study
is they showed there was an increase in health span,
which ultimately to me is the more important thing.
All right, next up @BDolanSFR asked,
"What are the neurological effects of excessive consumption
of the modern American diet
over the lifespan of an adult male?
How many 60s and 70s babies
are experiencing pre-diabetic irritability
and accelerated brain aging
due to a lifetime of eating garbage?"
The American diet is shit,
and it's not good for the aging process,
and we actually need to change our dietary habits
if we want to live longer, healthier lives.
And this can be even more problematic
for people who have genetic predispositions
to some of these diseases of aging.
So, you can imagine the average American diet,
which is basically the McDonald's diet,
could be really problematic
to someone whose body is actually not doing quite so well
in this area.
And finally from @drroyps,
"Medical science have made great strides and thus longevity,
and life expectancy has increased significantly.
Major pitfalls has been the exponential rise in dementia,
cognitive impairment and Alzheimer's.
Is there anything to rejoice?
These conditions are worse than death!"
So ideally what we would want
is not for people to spend 60 years disease-free,
then develop a disease
and then you keep them alive for another 40 years,
we actually want them to stay disease-free
for let's say 95 years, maybe do have the disease,
and then you only have five years with that disease.
So this is what we call health span extension
rather than just lifespan extension
and it's really what we need to work towards.
All right, so that's it for now,
thank you so much for your questions,
I think they were great ones
and I hope you guys learned something.