Is Obesity a Psychological or Physical Problem?

Carl Thompson was Britain's fattest man. Earlier this year, the 910-pound 33-year-old died in his home. It took emergency services several hours to remove his corpse from his flat in Dover, Kent. How did Thompson get to this point? The simple answer is that he ate a lot. Why do people like Thompson eat a lot? There's no clear-cut explanation, but many psychologists would argue Thompson suffered from a mental illness that compelled him to eat.

According to the Telegraph, UK Prime Minister David Cameron is set to announce that anyone diagnosed as clinically obese who refuses to seek treatment could see their benefits cut or suspended. "We must look at what we do when people simply say no thanks and refuse that help, but expect taxpayers to carry on funding their benefits," he expected to say.

But what's the best to treat those who are clinically obese when many people's obesity is arguably due to their mental health, meaning "dieting" just won't cut it?

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In 2013, the Guardian reported that 67 percent of men and 57 percent of women in the UK were overweight or obese (in the UK, a person with a BMI of 25 to 29.9 is considered to be overweight, and a BMI over 30 is considered to be obese). The same study found 71 percent of US men were obese, compared to 62 percent of women. Obesity can be caused by a number of factors, one of which is overeating—compulsive eating, without purging, that is usually done with discretion.

The question remains: where does overeating come from? What makes someone like Thompson literally eat themselves to death? Is there a genetic disposition to it, or is it a case of nurture over nature?

Dr. Cary Savage, director of the Center for Health Behavior Neuroscience at the University of Kansas, has worked for many years to uncover brain differences in obese and healthy weight people. "Words like willpower imply a certain dichotomy that either you have it or you don't," he tells me. "In reality, it's more complicated."

By scanning children as they looked at different food logos, Savage discovered obese children's prefrontal cortices (the area of the brain involved in control) were less active—suggesting they were more susceptible to food advertising. "We don't know cause and effect yet," he says. "We don't know if it's because people are born more susceptible to this or if it's the result of poor eating habits over time."

One thing it demonstrates, however, as Savage emphasizes to me, is that "none of us have perfect control over our behavior."

Daniel Pérez is a 20-year-old from Barquisimeto, Venezuela, who, last year, reached his heaviest weight of 379 pounds. He currently weighs just over 230 pounds. Thin as a child, Pérez believes his poor eating habits were a result of psychological triggers. After his brother passed away of heart disease when Pérez was just seven, he was heartbroken, devastated at seeing his mother cry for months on end.

"Eating became an addiction to me," he says, "and the most addictive foods were carbs. Pastas specifically. I would eat pastas three times a day, at least five days a week. It became so bad that my parents had to throw away leftovers when everyone was done eating."

Pérez's brother's disease made him extremely thin, and Pérez recalls being shocked at being able to see his bones. "I think all of this really had an impact on me," he says. "Being a small kid and not wanting to go like him definitely helped me to binge eat."

Pérez is not alone in believing his eating problem was down to a psychological trigger; Carl Thompson had also discussed how his issues worsened after the death of his mother.

Dr. Jen Nash is a member of the British Psychological Society and founder of Eating Blueprint, the world's first exclusively psychological weight-loss solution. Nash notes that there is an established body of evidence that, for many people, psychological issues are at the root of their overeating. "For some, this fundamental issue may indeed be grief—as with Thompson and Pérez—but there are a multitude of other factors, including trauma and abuse, particularly in early life," she says.

"Overeating" isn't classified as a psychiatric disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), the American Psychology Association's official catalogue of mental disorders, which is also used in the UK. "Binge eating," however, is. "Overeating is a challenge for many Americans," it reads, but "recurrent binge eating is much less common, far more severe and is associated with significant physical and psychological problems."

And what about food addiction? "Obesity is a complex issue, and food addiction is a relatively new and controversial term," says Nash. "Although food addiction does have a number of similarities to other addictive behaviors, we do not yet have enough data to fully and confidently conceptualize it in this way."

"I've actually spoken with a therapist," says Brian, a 27-year-old from Buffalo, New York, who weighs 400 pounds. "I asked if there was help out there for obese people, the same way that alcoholics can get help at a rehab center. I was told that unless I go on 'one of those TLC [competitive weight loss TV] shows,' there was not. Maybe I should start drinking more so I can get some help."

Of course, some overweight people do not identify with the idea that they are suffering from an addiction—or whatever you want to call it: overeating, compulsive eating disorder. Steven Sherman is a 29-year-old from New Ulm, Minnesota. He currently weighs 266 pounds, but at his heaviest was 399 pounds. He feels that, often, people use psychology and biology to excuse their own behavior. "I would definitely consider my weight my own responsibility," he says.

Sherman claims he sees his overeating as a cause of bad mental health, rather than the effect of it. "I used to break out sweating doing almost any physical activity, which would give me a certain level of social anxiety," Steven told me. "Now I don't need to deal with that any more. Overall I feel much better." He's lucky that losing weight helped him to deal with his anxiety, but other sufferers may have to confront the psychological issues first before they can shed the pounds.

The main issue with food addiction and overeating not being classified in the DSM-5, and being widely considered as biological issues, is that there is not much psychological support out there. Cameron wants British people who are obese to seek treatment, but, as Nash puts it: "The challenge we have in the NHS [National Health Service] is that obesity is dealt with in medical settings and in a medical paradigm, and so medical causes and solutions are the primary approach. This is slowly changing—NHS Weight Management Tier 3 services now should have a clinical psychologist in their multidisciplinary approach to supporting people to lose weight."

The complex experiences of Thompson, Pérez, Brian, and Sherman demonstrate that there is no clear and proven connection between obesity and mental illness. "We know people who are depressed are more likely to be obese, and people that are obese are more likely to be depressed," says Savage. "In most cases, what we don't know is which is cause and which is effect."

Ultimately, we cannot attribute morbid obesity to one factor—be it biology, psychology or addiction. In cases like Thompson's, it is likely that all these factors come together. "Words like blame imply total fault—there are often more factors involved," says Savage. "We all have the ability to make choices. For some of us, that is more challenging, because of our genetics, our hormones, our learning history, our environment, our parents, and what we were taught—all of these things work together to sabotage control."

Many of us, overweight or not, lose control daily. Most people are guilty of eating for reasons other than hunger. If you examine your own life, you can see that overeating often has psychological triggers, even if there isn't one underlying psychological disorder. The real—and perhaps scariest—lesson, then, seems to be that the capacity to become 910 pounds is within us all, somewhere on a deep psychological level. The British government's framework for the treatment of obesity—and the overeating that causes it—needs to reflect that.

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