
The science of grief and how it can impact physical health
9/18/2026 | 26m 46sVideo has Closed Captions
The science of grief and how it can impact physical health
If we are lucky enough to live full lives and form meaningful relationships, chances are, we will also experience loss, and with it, grief. As common as grief is, it’s also mysterious. Horizons guest moderator Ali Rogin explores the science of grief with Liz Gleeson and Dr. George Slavich.
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The science of grief and how it can impact physical health
9/18/2026 | 26m 46sVideo has Closed Captions
If we are lucky enough to live full lives and form meaningful relationships, chances are, we will also experience loss, and with it, grief. As common as grief is, it’s also mysterious. Horizons guest moderator Ali Rogin explores the science of grief with Liz Gleeson and Dr. George Slavich.
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Learn Moreabout PBS online sponsorshipI'm Ali Rogin and this is "Horizons."
William Brangham is away.
The loss of a loved one is all-encompassing, a toll that's felt not just psychologically but throughout the entire body.
How does such a prolonged stress response impact physical health?
And what happens when the mourning process feels inescapable?
The science of grief coming up next.
♪ Narrator: Support for "Horizons" has been provided by Steve and Marilyn Kerman and the Gordon and Betty Moore Foundation.
Additional support is provided by Friends of the News Hour.
♪ This program was made possible by contributions to your PBS station from viewers like you.
Thank you.
From the David M. Rubenstein Studio at WETA in Washington, here is "Horizons" from PBS News.
Welcome to "Horizons."
If we are lucky enough to live full lives and form meaningful relationships, chances are we will also experience loss and, with it, grief.
As common as grief is, it's also mysterious.
It often comes in waves.
For some, it's more sudden pangs of longing.
Experts say one thing is clear.
There's no such thing as a standard grieving process.
For most of us, though, there's a transition period where the acute pain fades and we learn to live alongside it.
But in recent years, there's been a recognition that some people stay in that period of intense grief.
In 2022, this condition was given a name, "prolonged grief disorder," and a place in the American Psychiatric Association's diagnostic manual known as the DSM.
Someone might be experiencing it if, one year after a loss, they have a feeling that part of oneself has died, intense anger, bitterness or sorrow, and difficulty reengaging with life.
But how do we distinguish between what we might clumsily call "normal grief" and a medical condition?
What do we know about the ways grief literally stays in our bodies?
And in our grief-illiterate society, how can we support one another?
We have two experts joining us this week to help us make sense of it all.
Liz Gleeson is a grief specialist and the director of Shapes of Grief, an online training program and podcast.
And Dr.
George Slavich, professor of psychiatry and human behavior at UC Irvine.
Thank you both so much for being here to talk about this important topic.
Dr.
Slavich, I'd like to begin with you.
Many of us are familiar with the concept of grief.
A lot of us have been through it ourselves.
But in a clinical, in a scientific sense, what is the precise definition of grief?
Well, thank you for having me.
I know a little bit about grief.
I recently lost both of my parents.
My father was a larger-than-life figure and my mom was incredible.
The experience of grief is such a natural part of human life.
It's something that we experience on a year-to-year basis.
Sometimes it's profound.
What we know scientifically is that close social relationships are so important for survival.
I mean, they provide physical protection but also social comfort and support.
And in the case of romantic relationships, close social bonds also increase our likely reproductive success.
We call that kind of protection "social safety."
When we lose somebody close to us, it doesn't just impact us emotionally.
It can also impact our brain and our immune system.
And in some cases, that biological response is short-lived, but in other instances, grieving can go on for months or years and in some instances really affect our lives.
Rogin: George, I'm so sorry to hear of the passing of your two parents.
I'd also like to ask you about the impact of grief.
You've looked into this extensively on the cellular level.
How does it end up affecting our genetic makeup?
Well, we all know that and we learned that we get half of our genes, our genetic code, from our mom and half of our genetic code from our dad.
You can think of that as sort of your genetic machinery or computer hardware.
As it turns out, that computer hardware doesn't really affect our health and our behavior unless the hardware is turned on, like when you turn on your computer and then open up a software program.
And at that point and only that point, do our genetics really affect our health.
And what we found in 30 years of research is that experiencing grief and social loss doesn't just affect our mood and emotions, but can also strongly affect the genetic programs or the software that are activated.
And in some cases, those genetic software programs can lead to very quick increases in inflammation, which is characterized by the expression of genes that promote inflammation throughout the body and also reduction in the activity of genes that support fighting off viruses.
So when we experience close social loss, we have increases in the expression of genes that increase inflammation and a reduction in the expression of genes that fight off viruses, which can make us both feel inflamed and also lead us to get sick.
Wow.
Liz Gleeson, to you, we mentioned in our introduction this concept of prolonged grief disorder.
And I'd like to ask you, how do you see that as differing from what, for lack of a better word, we might refer to as a standard grieving process?
Yeah, thanks for that question, Ali.
And I guess we call it "typical grief" if there is such a thing, because everybody grieves differently and everybody grieves every loss differently.
And in a typical grieving process at those early days, those early weeks, those early months, we call our grief acute.
It's where the volume is up.
We're living our life through the lens of loss.
And this sense of their absence is never too far from us.
And gradually over time, as we express our grief and engage with the grieving process, over time, we begin to carry this.
We begin to learn how to adapt to our loss and how to adjust to life without our loved one.
In the case of prolonged grief disorder, something happens that adaption process and it doesn't quite work the same way.
So we don't have stages of grief.
That's a myth.
There's no linear process that we follow.
It's much messier than that.
But we do, for most of us in a typical manner, we would experience this acute grief and then over time learn to carry our grief and integrate it.
With prolonged grief disorder, we're not integrating it.
So we're not learning to adjust to life without our deceased loved one.
The volume stays up.
The pain is immense.
The yearning doesn't abate.
And we're very much looking towards the past all the time rather than being able to engage in present activities or even visualize future activities.
And George, this is a relatively new name that's been given to this condition and diagnosis.
With that, I wonder, what do you think of the pros and cons of assigning a name and a diagnosis to something like that?
I think we need to remember that grief, prolonged grief disorder, just like all psychiatric disorders, are not inherent principles of the world.
These are social, psychological, medical constructs that have been defined by psychiatrists and psychologists, really in an attempt to make sure that people who need help the most get it.
So diagnoses like this one serve a lot of functions.
They can help medical professionals communicate with one another to make sure that your medical team knows what's going on.
They can also help to cover the cost of psychotherapy or other types of therapies that may help you get through a difficult time.
At the same time, especially a construct like grief has a huge social and cultural component.
So we have to ask the question, what is a normative amount of time to grieve?
Should it be a few days, a few weeks, a few months, or a few years?
And of course, our expectations around what is quote-unquote "normal" and what is quote-unquote "abnormal" will differ from person to person, but also differ from culture to culture.
So I would say in a nutshell, the advantage is that it helps us get the therapies we need.
It helps us communicate to the people who need to know that something is going on.
It helps to define what is going on.
But at the same time, we have to ask if these experiences are in fact normative or if they are quote-unquote "abnormal" in some way that requires treatment.
And Liz, that distinction is something that you examine all the time working with the people who seek you out.
And I wonder, are there signs that you can look for to understand that somebody may not be experiencing a typical grief experience and perhaps might need some additional support for something like prolonged grieving disorder?
Yeah, absolutely.
And I think it is so important to distinguish between typical grief that endures because it often does endure, versus a debilitating condition, which is really interfering with my quality of life and my ability to engage with everybody in my life and my job and my family.
In my clinical experience, people come to me, and it could be two, three years, five years even, after the death of someone they love, and they feel like a shell of themselves.
They feel that they're performing wellness, performing coping, they're going through the motions, but nothing can help them unless you bring their loved one back.
And when we start to hear things like, "I should have been there, "I should have done things differently, "nothing will ever be the same again," that's where we know that somebody might be in trouble with some maladaptive thinking versus somebody who's crying on their child's fourth anniversary.
And because grief is still present years on, it doesn't mean that it's prolonged grief disorder.
And so I just really wanted to make that distinction.
But there are treatments available.
Dr.
Kathy Shear at Columbia University has developed a really useful program called Prolonged Grief Therapy, and it has great outcomes for people who really want to... it's not about getting your grief away or, you know, curing the grief, but what it is it's helping people to grieve in a more typical manner that gives them hope for the future again, and allows them to engage with life again, and find meaning in life again.
Well, and Liz, I want to stay with you and ask, in terms of that more typical process, how do you help a person, when someone comes to you, how do you help them navigate their grief?
Gleeson: And I guess that's so different, whether you're a clinician, a counselor, or a friend.
But at the bottom line for everybody, everybody needs humanity, Ali.
You know, this is, you know, for many people, a profound loss absolutely rocks their world.
And as George has said, it can impact every part of our bodies, and we can feel incredibly vulnerable.
So we know that, you know, not everybody needs grief counseling at all.
In fact, most people don't.
Most people will, you know, adapt to their life without their loved one with the support of community and family and friends.
So that's already the best protective factor, is just showing up.
We need to acknowledge the loss.
That's very important because a lot of people think, "I'm not going to say anything "because I don't want to upset them."
But actually, in not acknowledging a loss, we can really do a lot more harm.
So acknowledging the loss and validating the emotions that somebody might be having, normalizing their experience.
We try to not give advice or offer platitudes, you know.
So anything that begins with, "At least they had a good life," is minimizing the experience.
So showing up, offering your time.
It could be being an ear for the telling and retelling of the death story, which is often very important for people to try and make sense of what happened.
Or it could be practical tasks.
And it's often actually those practical instrumental tasks that are very helpful for people right in the aftermath of loss.
But being there for the long run, this isn't something that's done and dusted over a couple of weeks, you know.
It's being there as your friend or your loved one adjusts to life again after this significant loss in their lives.
I'd like to ask you both about a real kind of global collective grief experience that all of us endured just a few years ago, and many are still going through.
And that is, of course, the COVID-19 pandemic, where many, many people lost loved ones.
And those who didn't were also going through a grieving process of some sorts, just mourning the loss of whatever their life was before the pandemic.
And I wonder, what in your observations, George, let's start with you.
How did the pandemic affect the way we grieve in our society?
Yeah, Ali, I would completely agree.
I mean, for me, the pandemic was really the great awakening, the worldwide great awakening for grief and trauma.
Before the pandemic, I would speak to folks, and many felt like they were thriving, at least in some aspects of their life, either at home or at work, or in activities they enjoyed, or in all three.
And since then, many people come to me clinically or personally and say that they feel like life is a struggle in one or more of those domains.
And that's, of course, occurred for many reasons, some of which involve social relationships, others of which involve inflation, etc.
But I think that one thing we can't deny is that the pandemic really isolated us fundamentally from one another, especially in some organizations, in some cities and communities and countries.
And in doing so, the pandemic and pandemic-era policies really damaged the basic social support networks and social fabric that keep us feeling emotionally grounded and socially connected on a day-to-day basis.
So all of the emotional and social warmth and predictability and dependability that is conferred by having normal social relationships really dissipated during the early days of the pandemic, but for many of us, continued for years afterward.
And although it feels like we're sort of on the precipice of some normalization, many people still come to me and feel and say that the social networks, the quality of the social networks that existed before the pandemic is still not fully constituted.
And that's something that I think as a society, we need to have an intentional effort toward continuing to foster.
And organizations, some workplaces still have work-from-home options, which make it a challenge to reconstitute some of those work relationships that really made us feel full before the pandemic.
So this is a continuing challenge that I think many of us face on a day-to-day basis, and something that, if we could get right, would really be a source of individual and collective resilience going forward.
Liz, how about you?
Gleeson: Yeah, I wholeheartedly agree with everything George said there.
Community is everything.
Relationships are everything.
And when it comes to bereavement outcomes, we know that social support, you know, is the best indicator of how somebody is going to do after experiencing a significant loss.
I lost my own father, actually, during the COVID pandemic.
And just navigating that tiny funeral, there was 10 of us allowed there, we weren't even sure if the whole entire family would be able to go to his funeral.
And, you know, I still miss the fact that we didn't have that celebration.
I think a celebration of his life, I should say.
But I think for a lot of people, they didn't go out at all during COVID and then never reemerged.
And this is dire, our society more than ever, you know, where we celebrate individualism so much.
We really need to get back to social connection.
We need to get back to community.
And as George alluded to there, it's important to have a social network and to have friends and to have family who we see regularly.
But it's the people down the street, it's the person who I order my latte from, it's the people I go past when I'm walking in the morning, and those micro moments of connection that really keep us well in the world.
And so I'd really love to see anybody working in the area of grief and loss, supporting more community rituals.
I recently started a grief cafe in my community, just as an act of service to bring people together so they can normalize their experience of loss and grief, make friends, take off the mask for an hour, and not have to perform wellness as we so often do.
It's all about community, connection and holding our grief collectively rather than the loneliness of trying to manage something you don't fully understand on your own.
Pervading this whole conversation, I think, and I want to address it directly, is this idea that we in Western society, broadly speaking, you know, George and I are in the United States, Liz is in Ireland, we're bad at talking about death.
We're bad at talking about grief and the realities behind them.
How can we get better?
And also, what can we learn from other cultures who have different ways of dealing with the inevitable like this?
George, let me start with you.
Slavich: The best piece of, or I should say, the best comment that somebody made when my father passed away was that my dad went from being here to being everywhere.
And I thought that was incredibly profound.
I mean, what it said to me was that, of course, the idea, all of the ways in which my dad imprinted ideas, values, motivations on me over, you know, the then 45 or so years of my life, those are all things that will never go away.
They're an inherent part of who I am.
They're an inherent part of my relationship, my experiences, my identity.
And I think acknowledging that and honoring that when we lose somebody important to us is extremely important.
Of course, in a physical sense, they may not be in front of us every day, but that aside, they always leave this indelible and oftentimes very valuable imprint on us.
And finding space in our minds and our hearts to keep people with us in that way, I think, can offer a really profound sense of comfort and meaning and purpose, despite them not being physically present.
So in addition to, of course, staying connected to the other people in our social networks, I think it's important to honor and keep in mind what those who have left us have really given us and how those experiences will continue on with us for years and years to come.
What a beautiful sentiment, this idea that your father is not here, but he's everywhere.
That's just really touching.
Liz, how do you see these entangled questions?
I would love to see us take grief back to the community, Ali.
I think part of the problem is, you know, dying and death have gone to the hospitals out of our communities, and people are living longer, right?
So we're not coming across death as often as our ancestors would have.
And so when it does happen, it's kind of hushed tones, and it feels like something intimate happening over there that we shouldn't get involved in, that it's not our business.
But I think we need to make it our business, because nowhere in our lives do we need connection and community more than when somebody we love dies.
So I think we need to take dying and death and grief back from the industries, you know, back from the medical industry, the pharmacological industry, the tech industry, you know, that's growing in this area now, and take it back to community and carry it together.
I think this is really, really essential.
I'm doing some research at the moment, Ali, with forest therapy for people after catastrophic loss.
So again, bringing people together, stepping out of that busy, capitalistic, productive world, back to nature, where we can experience time in a different way, we can experience place in a different way, and we can experience other people in a different way.
And I think that's what these really important rituals and times in our lives need.
It needs, you know, that honoring, that place, that space, that time devoted to them, and we need each other.
We need to move towards people who are at, you know, the end of their life, or who are supporting a loved one at the end of life, or, you know, someone who's grieving.
Go towards them.
They mightn't want us, but it's better to try than not try at all.
And that's what I'd really recommend to people.
Move towards suffering to alleviate it.
Sit alongside grief.
George, we have about 45 seconds left.
What more do we need to learn?
What don't we know about the ways grief affects us, both in the short and long term?
I know that's a lot to handle in now about 30 seconds, but give it a shot.
What I would say is that democracy dies in disconnection, and in fact, we die in social disconnection.
So I think we understand how grief affects the brain and the body.
I think what we need to focus on is how to get over this individualistic culture and give people the skills, the motivation, the purpose, and the drive to reconnect no matter what.
I think civilization depends on us doing that and doing it well.
Rogin: Liz Gleeson and George Slavich, thank you so much for joining us for this really fascinating and important conversation.
And that's it for this episode of "Horizons."
You can watch us on YouTube or listen wherever you get your podcasts.
If you like what you hear, subscribe and give us a rating.
It will help more people see the program.
Thank you so much for watching.
We'll see you next week.
Narrator: Support for "Horizons" has been provided by Steve and Marilyn Kerman and the Gordon and Betty Moore Foundation.
Additional support is provided by Friends of the News Hour.
♪ This program was made possible by contributions to your PBS station from viewers like you.
Thank you.
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