[Music] can you imagine a blessure so intense that you would be willing to give up everything you care for your family your friends your health your freedom just to temporarily experience it I certainly could not yet this was the way that the behavior of addicts was explained to me when I was a medical student and the way it's still explained by many in the healcare system a perspective that has helped promote the notion of addiction as moral failure but it's more incomprehensible than that because my addicted patients could not understand it either they said that the Lo drug was no longer even pleasurable and yet they could not stop taking it and this loss of control over one's own behavior Behavior intrigued me so much that I've been trying to understand how this would happen but where do you start by then we already knew from animal experiments that all of the drugs that produce addiction increase dopamine in the brain reward regions activating them however what happens in that transition from being able to occasionally enjoy a drug into the compulsive administration of addiction was a complete mystery I was very lucky that as I was finishing Medical School a new technology had emerged positron emission tomography that enabl us for the first time to image the living human brain to me as a young scientist this was like science fiction because it provided me with a tool that I could use to compare the function and biochemistry of the brain of a person that was addicted to drugs from that of someone who was who was not and this image here illustrates our first findings initially reported in cocaine abusers that we went there tend to replicate in metamphetamine abusers Alcoholics heroin abusers and what we found was that the brain of addicted individuals had a reduction in the levels of dopamine D2 receptors dopamine D2 receptors regulate the function of the frontal areas of our brain that allow us to exert self-control thus providing an explanation about why an addicted person would be more vulnerable to impulsive and compulsive Drug Administration these findings made me start to wonder whether something similar could be happening in obesity because after all most of these individuals want to lose weight but they cannot control their food in take so the same question can you imagine food being so pleasurable that you are willing to forgo 10 years of your life because of the adverse scale consequences from obesity or undergo the stigma from the disapprovals cast by others because you cannot hide obesity I certainly cannot think of such a food those we have apply the same methodology to investigate morbidly obese individuals and what we found was that just as for addiction their brains had a reduction in the levels of dopamine D2 receptors indicating to us that this was a biochemical signature of a brain where the capacity to control St strong urges has been compromise but why why why would this happen our brains are hardwired to respond to rewards which then motivates our actions reward is a brilliant solution to ensure that we will do behaviors that are indispensable for the survival of the individual and of the species because after all if food or sex were not rewarding we would not eat or procreate and dopamine is the chemical that signals reward in our brains interestingly dopamine is increased not just by rewarding pleasurable stimuli but also by stimula that predict a regard which we call condition stimul and again this is a brilliant solution because when you increase dopamine in your brain that enhances the motivation and sustains the drive for you to do the behaviors that are necessary to procure the reward therefore ensuring that you will go and get the food so you can eat it for example this great looking chocolate that visual of this great looking chocolate is making me want to eat it now and if I had it now I would eat it my brain is conditioned to Chocolate so that mere visual is making my brain predict that it's going to get a reward and dopamine is going up in my brain just by visually observing that stimuli which then makes me want to eat it most of the time I'm actually able to resist that urge of wanting to eat that chocolate sometimes I fail and I feel very guilty later and I find myself that I'm much more vulnerable to failing and to not be able to resist the temptation when I'm hungry and the hungrier I am the worse it gets but this makes sense when my brain is hungry and particularly if I am starving my brain gets into a state that I like to call of deprivation in the state of deprivation the main priority of my brain is to find the food so I can e it because for most of human evolution food was scars and hard to come by so you want to ensure that you would pay attention so that you would do the behaviors so that you could eat because otherwise you may not survive however in our current environments where food is everywhere this has become a liability and in fact I find myself constantly actively having to suppress the urge to eat all of this extraordinary looking food that is every were food stimuli are everywhere visuals auditory smell and when I eat the food when I cannot resist it I eventually feel satiated and when I'm satiated the food stops being rewarding to my brain which then of course enables me to change my behaviors and to do things that in the past may have had an advantage over my survival later however our modern societies have engineered highly rewarding food that can byass that satety mechanisms these are food that are rich in Sugar fat and salt and these are foods that can trigger compulsive overeating in almost every one of F these foods are the ones that can create havoc in the brain dopamine reward system highly rewarding food just like drugs produce sharp and short lasting increases in dopamine and the repeated and frequent Administration progressively leads to a loss of dopamin D2 receptors which then compromises our ability to control the strong urges to eat this very appealing food obesity just like addiction represent extreme consequences of the disruption of the systems in our brain that enable us to balance between immediate rewards that enable us to get take care of immediate needs and behaviors that may have an advantage later once those immediate needs have been accomplished addiction and obesity have been stigmatized and dismissed as disorders of poor self-control self-inflicted personal behavioral choices personal behavioral choices you know I've never ever met an addicted person who wanted to be an addict nor have I ever met an obese person who wanted to be obese their dismissal are just problems of self-control can you imagine can you imagine what it must be to want to stop doing something and not be able to do it and you try and you fail and you try again and you fail again and again and you start hating yourself for not being able to do it I don't need to imagine I can't remember my f grandfather took his own life at his inability to control his alcoholism one final and last relapse and his surrender to self-hatred or my obese adolescent patient who contemplated suicide to escape the Relentless and cruel bullying from her peers dismissal of addiction and obesity as just problems of self-control ignores the fact that for all to be able to exert self-control we require the proper function of the areas in the our brains that regulate our behaviors in simple terms and taken to the extreme it's like driving a car without brakes no matter how much you want to stop you will not be able to do it some of us because of our genetics our developmental trajectories our social circumstances are more vulnerable to these disorders than others and though we don't know yet how to remediate the genetic and developmental vulnerability factors we already have the tools to address the problem of obesity and of addiction because for the most part obesity and addiction can be prevented the current problems that we are facing of obesity are not the result of mutations in our genes but of the dramatic changes in our environment that have occurred over the past decades we humans Excel at our ability to change environments so why can we not reengineer them so that instead of making us vulnerable they strengthen our biology we know how to prevent obesity we've done it in the past in small communities the challenge is not not knowing how to do it the challenge is in committing the resources now to create an infrastructure that provides with options and Alternatives but real options and real Alternatives why can't we not have food that is healthy appealing accessible and affordable why can we not generate environments where that promote rather than hinder physical activities the challenge is in committing the resources now to build an infrastructure that will provide with real alternative and real choices for everyone not just those that can afford it some will argue that creating such an infrastructure will be costly now one can counter argue that this will be more than ofset that by all of the savings from averted medical cost plus the economical growth of a new food industry so can we can we all imagine can we all imagine committing now committing now for something that will provide us a much greater social benefit later I certainly can it makes sense not only will we save lots of money from averted medical consequences but we will improve the health of all of us and that of the future Generations thanks [Music]