Death by overwork
The Japanese have a word for a global phenomenon
The Japanese have a word - karoshi (過労死). It means death by overwork.
Not burnout. Not exhaustion. Death.
Japan recorded 1,304 karoshi cases between April 2024 and March 2025.
The number is rising.
The first recorded case was in 1969. A 29-year-old man in the shipping department of a newspaper died of a stroke. He had been logging dozens of overtime hours every week. When he became physically ill, his employer did not reduce his hours. They increased them.
It took the government five years to acknowledge that the workload had killed him. Five years to admit what everyone already knew.
The language of devotion
To understand karoshi, we have to understand the culture that produces it.
Japan has a concept called sābisu zangyō (サービス残業). Unpaid overtime. The literal translation: overtime given as service or a gift to the company.
It is, technically, illegal.
It is also routine.
Then there is inemuri (居眠り). Falling asleep at your desk.
In Japan, this signals dedication. Proof that you worked hard enough to lose consciousness.
When you leave the office, colleagues don’t say goodbye. They say otsukaresama deshita. “You must be tired.” The implication being that if you’re leaving, you have worked yourself to the point of exhaustion, and that is something to be honoured.
Leave before your boss, and you signal something else entirely. That you care more about your family than your company. That you are not serious. That you cannot be trusted.
The language itself encodes the expectation.
The death of Matsuri Takahashi
Matsuri Takahashi was 24 years old Tokyo University graduate. Nine months into her first job at Dentsu, Japan’s largest advertising agency, she was logging up to 130 hours of overtime a month. Dentsu’s managers pressured staff to falsify their timesheets.
In her final weeks, Matsuri was getting only 10 hours of sleep in a week.
Her last tweet: “It’s 4 am, and my body’s trembling.”
She jumped from the company dormitory on Christmas Day 2015. Her death was officially ruled a workplace injury: suicide caused by depression, the primary cause of which was overwork.
Dentsu’s fine was the equivalent of $4,500.
After her death, Dentsu quietly removed a list of internal rules from its staff handbooks. Rules that had been in place since 1951. One of them, in approximate translation, told staff: never give up on a task, even if it kills you.
A global problem
The ILO estimates nearly 3 million people die from work-related causes every year. Long working hours are the single biggest occupational killer. Bigger than any chemical, machine or hazardous environment.
We built entire legal systems to protect workers from physical danger. We have almost nothing to protect them from the pressure to perform.
Karoshi has a Japanese name. The shadow behind it is universal.
Every culture inherited the same core belief: our worth is measured by our output. We just express it differently. Japan has inemuri and sābisu zangyō. Other cultures have inbox zero at midnight and “I’ll sleep when I’m dead” as a badge of honour.
Where this begins
This belief that value must be earned through effort doesn’t start in the workplace.
It starts much earlier.
Most of us learned as children that we were rewarded for effort, achievement, self-sacrifice, trying hard, being responsible, and being no trouble.
We learned that our value increased when we did more, and decreased when we rested.
And so as adults, we arrive at work already carrying the wound. Productivity becomes a way to earn respect and a sense of belonging.
The workplace inherits this, and then it amplifies it, rewards it, and calls it high performance.
The part of you that checks emails at 10 pm and tells yourself it’s fine.
The part that doesn’t take the holiday because “the timing isn’t right”.
The part that measures its value by its output and starts to panic during a slow week.
That part that learned very early that stopping was dangerous.
It is doing exactly what it was taught to do.
The mirror
The culture described here is not universal in all Japanese firms. But it does exist. And it’s a mirror.
It shows us the shadow of productivity. When exhaustion becomes virtue.
The shadow doesn’t disappear when we ignore it. It builds pressure. And eventually, in one form or another, it finds a way out.
For Matsuri Takahashi, the pressure had nowhere left to go.
The question karoshi asks all of us is not: how do we fix Japanese work culture?
The question is: what am I trying to prove, and to whom am I trying to prove it?
And when did I learn that my worth depended on my workload?