But then something strange happened. In the program, there were some stars ― people who shed incredible amounts of weight, and the medical team ― and all their friends ― expected these people to react with joy, but the people who did best were often thrown into a brutal depression, or panic, or rage. Some of them became suicidal. Without their bulk, they felt unbelievably vulnerable. They often fled the program, gorged on fast food, and put their weight back on very fast.

Felitti was baffled ― until he talked with one 28-year-old woman. In 51 weeks, Felitti had taken her down from 408 pounds to 132 pounds. Then ― quite suddenly, for no reason anyone could see ― she put on 37 pounds in the space of a few weeks. Before long, she was back above 400 pounds. So Felitti asked her gently what had changed when she started to lose weight. It seemed mysterious to both of them. They talked for a long time. There was, she said eventually, one thing. When she was obese, men never hit on her ― but when she got down to a healthy weight, for the first time in a long time, she was propositioned by a man. She fled, and right away began to eat compulsively, and she couldn’t stop.

This was when Felitti thought to ask a question he hadn’t asked before. When did you start to put on weight? She thought about the question. When she was 11 years old, she said. So he asked: Was there anything else that happened in your life when you were 11? Well, she replied ― that was when my grandfather began to rape me.

As Felitti spoke to the 183 people in the program, he found 55 percent had been sexually abused. One woman said she put on weight after she was raped because “overweight is overlooked, and that’s the way I need to be.” It turned out many of these women had been making themselves obese for an unconscious reason: to protect themselves from the attention of men, who they believed would hurt them. Felitti suddenly realized: “What we had perceived as the problem ― major obesity ― was in fact, very frequently, the solution to problems that the rest of us knew nothing about.”

This insight led Felitti to launch a massive program of research, funded by the Centers For Disease Control and Prevention. He wanted to discover how all kinds of childhood trauma affect us as adults. He administered a simple questionnaire to 17,000 ordinary patients in San Diego, who were were coming just for general health care – anything from a headache to a broken leg. It asked if any of 10 bad things had happened to you as a kid, like being neglected, or emotionally abused. Then it asked if you had any of 10 psychological problems, like obesity or depression or addiction. He wanted to see what the matchup was.

Once the numbers were added up, they seemed unbelievable. Childhood trauma caused the risk of adult depression to explode. If you had seven categories of traumatic event as a child, you were 3,100 percent more likely to attempt to commit suicide as an adult, and more than 4,000 percent more likely to be an injecting drug user.

After I had one of my long, probing conversations with Dr. Felitti about this, I walked to the beach in San Diego shaking, and spat into the ocean. He was forcing me to think about a dimension of my depression I did not want to confront. When I was a kid, my mother was ill and my dad was in another country, and in this chaos, I experienced some extreme acts of violence from an adult: I was strangled with an electrical cord, among other acts. I had tried to seal these memories away, to shutter them in my mind. I had refused to contemplate that they were playing out in my adult life.

Why do so many people who experience violence in childhood feel the same way? Why does it lead many of them to self-destructive behavior, like obesity, or hard-core addiction, or suicide? I have spent a lot of time thinking about this. I have a theory – though I want to stress that this next part is going beyond the scientific evidence discovered by Felitti and the CDC, and I can’t say for sure that it’s true.

“If it’s your fault, it’s — at some strange level — under your control”