No, there isn't a single hypothesis that covers ALL obesity.
But much of obesity has to do with the HPA axis dysregulation.
And there are lots of super-dysregulating paths that have not been a part of our thinking and discussion here..
There are many ways for the HPA axis to get dysregulated/inflammed, as well as for brain development to get very, very skewed (brain development is use dependent.) At certain times of your life prominently, for just one, in the early teens, your brain is busy pruning what I think of as neuronal "arbors" that are not used, and developing neuronal "arbors" like wildfire that ARE used. Depending upon what your brain is exposed to, this can be a big, big deal and spawn big, big problems. Just take one simple thought...we needn't get all fancy about this. What if your brain as a 14 year old is constantly experiencing insults due to the environment that make you spew cortisol(and other juicy chemicals!) like crazy. Do you think this might affect your brain? Do you think it is possible that these brain effects could be very wipespread, ie., affect more than one "function?"
So, let's look at some that we haven't looked at -
Let me say that with this link, I do not agree with the conclusion, but I understand that the conclusion had to be "sold" to the general public on a TV station, so it had to be greatly simplified. Perhaps you can apply your super hacker brains to what might be the effects in the brains of these people whose brains were bathed in at least cortisol, people who could be described as never feeling safe. Might they have developed some cortisol related conditions? Might an outcome of their brains being bathed in cortisol ad infinitum have led to the inflammation of the HPA that we know occurs through a variety of mechanisims, leading to probable depression, anxiety and other states originating at young ages, AND a high probability, in my opinion, of lots of endocrine system disruption/dyregulation that can greatly affect energy use and appetite/feelings of hunger?
In this link, I think that their projection that trauma (think: brain changes) becomes a path to obesity for about 8% of the obese is probably conservative. But still, combine that with Lustig's identification/defining of a syndrome of vagally mediated beta cell hyperactivity that leads to insulin hypersecretion and obesity and which is treated by insulin suppression, a phenomenon which may occur in about 20% of the obese population, and we are now batting about 28% of the obese population.That's a big chunk of the total.
Now, take a think on the following...The purpose of this "answer" (the entire post, including all of the above) is not to be an "answer." It is to broaden the thought pool for thinking about the question.
"This study not only confirms that ADHD is a highly prevalent condition in severely obese patients, but that the treatment of ADHD is associated with significant long-term weight loss in individuals with a lengthy history of weight loss failure.
Levy suggests, as I did in earlier postings on this topic, that ADHD should be considered as a primary cause of weight loss failure in obese patients."
"Attention deficit disorder with or without hyperactivity (ADD or ADHD) and impulsiveness has been associated with increased risk for weight gain in both children and adults. In one study, ADHD was present in over 25% of all obese patients and 40% of patients with class III obesity. Reasons for this prevalent co-morbidity are unknown, but brain dopamine or insulin receptor activity may be involved.
Patients with ADD or ADHD usually manifest a long history (since childhood) of impulsivity, lack of concentration, decreased attention, inability to complete tasks, impairment in school or work performance and social dysfunction. Being “hyperactive” in the sense of the DSM-IV diagnosis of ADHD does not prevent the development or persistence of overweight and obesity in children."
"Regular readers will recall that almost 30% of adults with severe obesity may have signs of attention deficit hyperactivity disorder (ADHD) and, when present, this can be a major barrier to weight management."
"Childhood maltreatment or adverse experiences in five domains (emotional abuse, physical abuse, sexual abuse, emotional neglect and physical neglect) have been reported as highly prevalent in patients with binge-eating syndrome. In one study, 83% of patients with binge eating reported some form of childhood maltreatment: 59% reported emotional abuse, 36% reported physical abuse, 30% reported sexual abuse, 69% reported emotional neglect, and 49% reported physical neglect."
Now, some more nice science background from one of the best of the best:
"Childhood is a dangerous time." "The home is the most violent place in America."
"We are not designed for this
modern world. The human brain is designed for the
natural world. Small, multi-generational
family groups living together."
And a piece of PubMed research, because PubMed excites us so:
For those who are prone to deeming the "psychological" to being "all in the head," be very, very clear that I disagree with you. And so does science.
With imaging, changes in the brain can be seen. Changes in the brain resulting from psychotherapy, which for too long was seen as another "all in the head" therapy, can also be seen/measured.
And to be really, really clear, nowhere in this post am I saying that if you are or have been a significantly overweight or obese person, that YOU suffered childhood trauma, have ADHD, or have suffered other linked adverse experiences.
This is a response to the question. And as I made clear from the outset, I do not buy into any single hypothesis for obesity, though I see some as far more compelling than others.
The purpose of this answer is to broaden the thinking field.
It is not to "prove" the information that I have presented, which is simply to get the "wheels turning."
I will leave you with a favorite quote:
"If 20 million people were infected by a virus that caused anxiety, impulsivity, aggression, sleep problems, depression, respiratory and heart problems, vulnerability to substance abuse, antisocial and criminal behavior, retardation and school failure, we would consider it an urgent public health crisis.(This was written in the mid 90's. Were Perry writing it now, he'd add obesity, I am sure.)
Yet, in the United States alone, there are more than 20 million abused, neglected and traumatized children vulnerable to these problems. Our society has yet to recognize this epidemic, let alone develop an immunization strategy." - Bruce D. Perry MD., PhD, The Child Trauma Academy