Bessel van der Kolk didn't think his book "The Body Keeps the Score" would be such a mainstream success.
Van der Kolk is a psychiatrist and researcher who has worked with trauma survivors for more than 30 years. His book seeks to educate readers on how trauma shapes the body and brain, and possible effective treatments.
It has remained on The New York Times bestsellers list for more than 245 weeks, and for at least 27 it was No. 1. Unlike other titles that sit atop a bestsellers list, the book is scientific and graphic.
Even today, almost 10 years after its initial release, "The Body Keeps the Score" is No. 15 on Amazon's bestsellers list, sandwiched between "The Complete Summer I Turned Pretty Trilogy" and "Pretty Boys are Poisonous," which is a collection of poems by actress Megan Fox.
"There is no precedent for this type of book so, no, we didn't know it would be this popular," van der Kolk tells CNBC Make It.
Other trauma experts are less surprised at the book's enduring success.
"A day doesn't pass without more traumatic events happening all over the world," says Janina Fisher, a trauma expert and licensed clinical psychologist.
'I think Trump being president had to do with it'
There is one singular event that van der Kolk says might have led to an uptick in book sales, and it's not the Covid-19 pandemic.
"The most common question from journalists is, 'what do you think about the trauma of the pandemic?' Well that wasn't a trauma," he says.
The traumas of clients in his book include rape and violent child abuse. And while there was an increase in anxiety and depression during the pandemic, those are not traumas.
Instead, he credits continuing popularity of his book to the 2016 United States presidential election.
"I think Trump being president had to do with it," he says. "He is so clearly an abusive man and it must remind a lot of people about the lying and manipulation and bullying of their own parents."
And it's not only former President Donald Trump's alleged actions or treatment of others, but how it was received by the public.
"What traumatized people suffer from is that people don't believe them or people minimize it or say, 'it didn't really happen,'" van der Kolk says. "People go through terrible things and the world around them says, 'just get over it, keep moving, it doesn't matter.'"
Trump's supporters, van der Kolk says, are known for either downplaying or condoning his behavior, which could remind trauma survivors of their own stories being ignored.
"The Kavanaugh hearings were a good example where a well-put-together person clearly tells a very believable story and the world goes 'let's ignore them,'" he says.
Fisher, who has worked with van der Kolk, emphasizes that "The Body Keeps the Score" remains relevant because of its content but also because of how it is written.
"It's very hard to write a book that contains so much information gleaned from so much research that is also so readable," Fisher says.
'This is not a saint versus sinner situation'
The book's popularity has led to the word "trauma" becoming commonplace, and often misused.
A boss who emails at midnight or a neglectful partner are all now labeled as "traumas."
Fisher uses a definition created by clinical psychologist and trauma researcher Karen Saakvitne.
It reads: "Psychological trauma is the unique individual experience of an event or of enduring conditions in which the individual's ability to integrate his or her emotional experience is overwhelmed (i.e. his or her ability to stay present, understand what is happening, integrate the feelings, and make sense of the experience), or the individual experiences (subjectively) a threat to life, bodily integrity, or sanity."
Misuse of the word, Fisher says, might have long-term consequences for those who have experienced truly terrible events.
"We have to be aware that if the trend continues we will dilute the term trauma so that it no longer has meaning," she says. "And those who have been human trafficked will be put in the same category as those whose parents were cold and critical. That's my fear."
Van der Kolk says that while he feels most readers use his research appropriately, he is wary of people using their own trauma to dodge accountability.
"What I am concerned about is the issue of victimology," he says. Someone thinking, "because I'm a victim I don't need to follow the rules or because I'm a victim I don't have to work hard. Most people who are in jail have trauma histories. Just because you have a trauma history doesn't mean you should be allowed to commit crimes. To use your terrible childhood as an excuse for your bad behaviors is somewhat troublesome."
Van der Kolk understands, though, that the idea that someone who is a victim can also be a perpetrator is an uncomfortable truth.
"A lot of people who have been victimized behave quite badly themselves," he says. "This is not a saint versus sinner situation."
How people use his work is, of course, out of his control.
Many experts, including Fisher, believe the book was written in a way that makes it clear what trauma is and how to treat it.
"I think 'The Body Keeps the Score' is a very responsible book," Fisher says. "It doesn't write about major mental illness as something all our loved ones have."
But it does recognize that trauma is frequent and affecting.
"There is still a need for this book," Fisher says. "The world is not getting less traumatic."
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