Why you never really die: A microbiologist explains all the ways the body lives on, and why we don't decay until we're dead
- "To Dust," a new film starring Géza Röhrig and Matthew Broderick, follows a grieving Orthodox Jewish husband as he tries to determine how long it takes a corpse to decay.
- The answer to that question depends on many variables, including how deeply a body is buried, the temperature of the earth, the soil makeup, and the insects present.
- According to microbiologist Maria Dominguez-Bello, life doesn't completely end when we die: Much of our matter becomes part of the environment, whether we're buried or cremated.
From Silicon Valley biohackers to those seeking transfusions of young blood, there are a lot of people out there who want to live forever.
But microbiologist Maria Dominguez-Bello says that in many ways, we already do.
Dominguez-Bello recently spoke at a screening of the new film "To Dust," which was released in theaters on Friday.
The film won the prize for best new narrative director at the 2018 Tribeca film festival, and it's a surprisingly hilarious journey through spousal grief.
Hungarian actor Géza Röhrig stars as Shmuel, a grieving widower whose wife has died of cancer, leaving him and two young sons behind. Matthew Broderick plays a community college science professor who Shmuel recruits to help him figure out how long it takes a human body to decompose.
Specifically, the pair is concerned with Shmuel's wife's body, which was buried in white shrouds and placed in a wooden coffin, according to Orthodox Jewish practices. Shmuel desperately wants to know how long it will take her to return "to dust," as is mentioned in Jewish scripture:
And the dust returns to the earth as it was, and the spirit returns to God, Who gave it.
To Dust/Good Deed EntertainmentGéza Röhrig plays Shmuel, a widower who lost his wife to cancer.
Wanting his beloved wife to rest in peace with God as soon as possible, Shmuel won't rest well until she can fully decompose.
In their attempts to figure out how long that will take, the pair buries numerous pigs, visits a restricted body farm, and performs bubbling, oozing lab experiments. The movie is a touching reminder that grief looks different for everyone.
How long does it take a human body to decay? It depends.
Dominguez-Bello, who studies the human microbiome, said that when we die, we return to nature. But how long that process takes is a complicated question.
The amount of time it takes a single body to decompose depends on a whole range of variables, as Matthew Broderick's character points out in the film. That makes it near possible to determine how long a body will remain intact in the ground.
The factors at play include how deeply a body is buried, the temperature of the earth in that area, the soil makeup, and the insects present. In the arid Arizona desert, for example, scientists have found that it can take about nine months for a person's skeleton to start to crumble.
Furthermore, because human decay is a process that starts from the inside out, decomposition looks different for different people and will be influenced by the state of their microbiome at death. Researchers have observed that certain parts of a person's body may decay slower or faster than other sections, making it impossible to draw firm conclusions about when a corpse is done.
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How humans live on after we're dead
Once a human dies, a chain reaction kicks off a feeding frenzy that reverberates through the environment. A person may be dead, but there is still a lot going on.
The microbial process of decomposition begins not in the environment surrounding a corpse, Dominguez-Bello said, but inside the body itself.
"When you die, there are no constraints anymore, there is no immune system," she said. "You become food for your own bacteria first, and then also bacteria from the soil."
Our immune system is a web of connecting tissues, organs, and cells that helps us fight off invading viruses and bacteria. While we're alive and healthy, invaders are up against tough odds. But that changes after our last breath, since the immune system shuts down.
That's why dead bodies decompose, but in a sense, it's also a way that our bodies live on after we die.
"Think of places where people are buried as places where the molecules of those people still are breathing," Dominguez-Bello said. "You know, the trees are growing thanks to their bodies. And there is some kind of poetry there."
A similar story is true of cremated bodies.
"All the organic matter, carbon, hydrogen and oxygen and nitrogen will go to the air," Dominguez-Bello said. "So people breathe it. The animals breathe it, and the inorganic matter goes back to the soil."
There's another way that our microbes live on after we die: If a woman has children, her microbiome gets passed on to future generations. That's because microbes "live in the females and will colonize the vaginal canal," Dominguez-Bello said, which is how mothers pass on their unique microbial flora to their babies.
"Humans are seeded with microbes by the mothers," Dominguez-Bello said. "The process starts at labor and birth."
In the movie, although Shmuel's wife is gone, this is another way that part of her may live on - not only through the DNA she passed on to their sons - but also more viscerally in the microbes she gave their tiny bodies at birth. Those microbes serve as some of the first critical pieces of the immune systems that keep her offspring alive.