i believe depression is oneof the most tragically misunderstood words in the entire english language. and here's the problem: depression has two radicallydifferent meanings, depending on the context. so, in everyday conversation, when people say they're depressed, they use the word depressionas a synonym for sadness. it's a normal human reaction
to the slings and arrowsof outrageous fortune. in that sense, all of us knowthe pain of depression. and yet, in a clinical context, depression is shorthandfor a devastating illness. did i get it? there it is, ok. for a devastating illness. we refer to it technically as major depressive disorder. this is an illness which robs people
of their restorative sleep, robs them of their energy, robs them of their focus, their concentration, their memory, their sex drive, their abilityto experience the pleasures of life. for most individuals, it robs them of their ability to love, and work, and play. it may even rob them
of their will to live,and i'll tell you why. because, we now know depression lights up the pain circuitry of the brain, to such an extent thatmost clinically depressed individuals, if you talk to them,and they let their guard down, they will tell you, as they've told me, hundreds of times: it's torment. it's agony.
it's torture. and many begin to look to death, as a welcome means of escape. depression is the main driverbehind suicide, which now claims overone million lives every year worldwide. now, i know what you're probablythinking at this point: man, this talk is going to be really... (laughter) you know, depressing.
so, i'm going to givea friendly little spoiler alert: it's not! it's truly not! depression, yes, it is a treacherous foe. but what i've found in my 20 years of clinical research and clinical work is this is a foe that can be defeated. that's the good news, and that's the newsthat i'm going to focus on for most of the talk tonight.
first, a little more bad news: depression is now a global epidemic. in fact, if we look in the us, we now findthat nearly one in four americans, will experience the agonizing,debilitating pain of depressive illness by the time they reach age 75. and it gets worse. the rate of depressionseems to be increasing generation after generation.
so, every successive birth cohort is having higher rates of depression, than the one that preceded it. now, i want you to look at these lines. we've got four different generationson this graph. the green line on the right, that's the oldest americans. and by the time they've made it out into their 60s and 70s,
they have a lifetime rateof depression of 10%. that's horrible, but it's much lower than every succeeding generation. now take a look at the linethat really upsets me the most: it's the one on the far left. that's our youngest american adults. you see what's happened? by the time they're in their mid-20a, they already havea rate of depression of 25%.
remember, we're talking about a potentially lethal, debilitating illness. left unchecked, it's an illnessthat can cause brain damage. and if we extrapolate that line, by the time they reach middle age, their lifetime rate of depressionwill already be over 50%. so what in the world is going on? what's driving the epidemic?
what can we do about it? what causes depression? well, on one level, when we ask this question, we're going to face the answerthat it's really complicated. there have been, literally, thousands upon thousandsof published studies that have identifieda dizzying array of factors that are implicatedin the onset of depression:
biological, psychological, cultural, social, behavioral. but if we wade through this complexity, what we begin to find, is that there's a commonunderlying pathway. a primary driver. a primary trigger. i call it the brain'srunaway stress response. now we all know the stress response.
we think of it, probably,as the fight-or-flight response in its most extreme form. i want you to think about that response. especially, how it was evolvedand adapted to serve us. the fight-or-flight responsewas designed primarily to aid our ancestors when they faced predators, or other physical dangers. they required what?
intense physical activity that would go on for a few seconds, for a few minutes, maybe, in extreme cases, for a few hours. it's a very costly response. but fine, if it shuts offwhat it's supposed to. here's the problem. for many americans, europeans, and people throughout the western world,
the stress response goes on for weeks, and months, and even years at a time. and when it does that, it's incredibly toxic to the bodyand to the brain. it's disruptive to neural circuitsin the brain that use neuro-chemicals you've heard of, like dopamine and serotonin, acetyl-choline, glutamate. this disruption can lead directlyto depressive illness.
it also can actually damage the brain, when left unchecked over time. especially in regions like the hippocampus which is involved in memory consolidationand the frontal cortex. it also triggers an inflammatory reaction throughout the body and brain. and here's what we've learnedabout depression: the inflamed brain is a depressed brain. now this is really intriguing,
because epidemiologistshave now identified a number, a big constellation of illnesses that are rampant and epidemic. throughout the entire developed world you can see the list: atherosclerosis, diabetes, obesity, allergies,
asthma, many forms of cancer, these are all inflammatory illnesses. they're all illnesses that are epidemic in the industrialized, modernized world and largely non-existent among modern day aboriginal groups. i believe we need to add depression, clinical depression,
to this list. it shows all the hallmarksof being a disease of civilization. and, you know what that means? it's a disease of lifestyle. so consider the experienceof the kaluli people, of the highlands of papua new guinea. they've been studied extensively, by the anthropologist edward shieffelin. he spent over a decade among the kaluli.
one of his research questions was, how often do the kaluli experience the same kind of mental illnessthat we do? he certainly found some forms of it. he interviewed over two thousandmembers of the kaluli, and extensively queried them for their experienceof clinical depression. and you know what he found? one marginal case out of 2,000!
that gives them a rateof clinical depression, that's probably abouta hundred times lower than ours. i'll tell you why i findthat really remarkable. because, among other things, the kaluli lead really really hard lives. really! they have high rates of infant mortality. they have high ratesof parasitic infections. they have high rates of violent death.
but they don't becomeclinically depressed! they grieve, absolutely. they don't get shut down. what's protecting them? lifestyle. specifically, the kaluli live a lifestyle very similar to that of our ancestors over the entire pleistocene epoch, that lasted for 1.8 million years.
did you know that 99.9% of the human and pre-human experience was lived in a hunter-gatherer context? so, what does that mean? most of the selection pressures that have sculpted and shaped our genomes are pleistocene. we're still really well adapted for that sort of environmentand that sort of lifestyle.
i'm not saying there hasn't beenany change since then. because, of course,10 to 12, 000 years ago, we had the invention of agriculture. and there has been some genetic selection over that period of time. it's been more minor. but what happened 200 years ago, with the industrial revolution? it's been termed"radical environmental mutation".
i like that term. it's as if modern americanand western life is radically discontinuous from everything that came before. our environment has radically mutated, but how much has the human genome changed over the last 200 years? it hasn't. it hasn't. that's eight generations.
it's not enough time. what does that mean? there's a profound mismatch between the genes that we carry, the bodies and the brainsthat they're building, and the world that we find ourselves in. i'm going to put it for youas fitfully as i can: we were never designed, we were never designed for this.
we were never designed for the sedentary, indoor, socially isolated, sleep-deprived, fast-food-laden,frenzied pace of modern life. the result? an epidemic of depressive illness. now, i'm a depression researcher. i was trained in a traditionalform of psychotherapy. i was trained in a context where i learnedall about antidepressant medications.
i want to tell you right at the outset:i am not anti medication. i believe in fighting depression with every possible tool that we have. but, you know what? if we only throw medicationat this epidemic, we are not going to fix it. at least we haven't so far. how much do you think antidepressant use has gone up
over the past 20 years? would you care to guess? (indistinct answers from audience) i like that guess. 1,700 %? it's gone up over 300%. so you're close. over 300%! and what's happened to the rate of depression in interim?
it's continued to increase. one in nine americans over the age of 12 is currently taking an antidepressant. one in nine! currently, one in five, according to some estimates, have tried it at some point. have we solved the epidemic? no, we haven't made a dent.
the answer, i believe,is the change of lifestyle. now, you'll see behind you a list of six lifestyle elements. when my research team and i, seven years ago, had this epiphany, we got together and we started scouringthrough the depressive literature, asking the question, „what are the kaluli doingthat's protecting them?†specifically, based on everythingwe know about depression.
what did our ancestors dothat protected them? we quickly found six factors that changed neural chemistry. six factors that are knownto be antidepressant. six factors that we can reclaim and weave into the fabric of our day-to-day life in the present. to protect ourselves... from this devastating illness.
and so, we designeda new treatment program. it's really ambitious, i admit that. did i think it would work? i really wasn't sure. you know what? i was not trained as a psychotherapist, as an interventionist researcher. i was doingbasic neuroscience psycho-pathology. but i had a passion to see this epidemic
brought to its knees. i had a passion to treat individuals whom i knew, who had tried everything, and were still depressed. and so, with great trepidation, we set out to design this program. the results have exceededmy wildest dreams! there are six major elements. i'm going to run though themas quickly as i can in our remaining time.
the first is exercise. now, exercise is good for us. how many of you--can i see a show of hands? how many of you came in here today knowing that exerciseis really really good for us? right? every hand goes up. now, has it changed your behavior? for some yes. everybody knowsthat exercise is good for us.
here's the problem: many people have trouble making it happen. and you know what? a lot of people don't realizejust how good exercise-- i'm going to say somethingthat may be a little bit controversial, and i am not speaking metaphorically:exercise is medicine. exercise literally is medicine. it changes the brain and the bodyin beneficial ways that are more powerful
than any pill you can take. yeah, i said it. more powerful than any pill you can... in fact, i'm going to say somethingeven more controversial. if you could take the neurologicaland physiological effects of exercise and capture them in a pill, all the beneficial effectsof neuro-signalling in the brain, the anti-aging effects all the way downto the level of chromosomes in every cell of your body,
the mental clarity enhancing effects, i believe, tell me if you think i'm crazy, i believe that pill would become the best selling drug of all time. and i think people would payany price to have it. there's a problem though. we don't exercise. we don't. cdc again tells usthat 60% of all american adults
get no regular physical activity. and yet, if we lookat hunter-gatherer groups, they get four or more hours of vigorous activity every day. in fact, they look like elite athletes. even when they're intheir middle age and beyond. here's the thing i love though: if you ask them, they will tell you they do not exercise.
they don't! they do not work out. working out would be crazy to them. what do they do? they live! here is... yeah, i know. i like it, too. here's the dirty little secretin the business. and i really want you, if you remembernothing else from this talk:
exercise is not natural. we are designed to be physically active in the service of adaptive goals. we are not designed to exercise. when you put a lab rat on a treadmill and crank that thing up to the point where it's moving fasterthan it wants to move, you know what it will do, if you let it.. it'll squat down on its haunches
and the treadmill starts to wear the furand the skin right off its backside. so, it kind of feels our pain, right? when you stareat a piece of exercise equipment, there's a piece of your brainthat's screaming out, "don't do it! you're not goinganywhere on that thing!†so how do we solve this conundrum? in our treatment program, we've done two things. we've made exercise natural,
and we've made it social. what's the most naturalactivity in the world? walking! and guess what? brisk walking, you know the kind? like you're late for the bus.like you might miss your plane. that kind of walking will getyour pulse up in the aerobic range, and that's where it needs to be. based on your age, depending on your age,your pulse needs to be between 120-150.
that's enough to enhance signaling in your dopamine circuits,your serotonin circuits. it's been tested head to headagainst zoloft twice. in the long term, it won. at what dose? thirty minutes, three times a week. that's a low dose. it can change your life. now, i wish i had timeto cover everything else
that we need to cover, but i'm going to tell you aboutone more thing: omega-3 fats. did you know that your brain is mostly made out of fat? did you know the brain is 60% fat by dry weight? so, if somebody calls you a fat head... they might be paying you a compliment.
all right, here's the thing: our bodies can make all the fatsthat we need, with two exceptions. they're called essential fats. you've heard of them,omega-6s and omega-3s. they play complementary rolesin the body and the brain. omega-6s are inflammatory. omega-3s are anti-inflammatory. we need them in balance. we're designed to have them in balance.
omega-3s come from grasses and plants and algae, and the animals that eat them. omega-6s from grains, and nuts, and seeds and the animals that eat them. which is, by the way, most of our meat supply. our hunter-gatherer ancestorsgot omega-6s and omega-3s in the optimal balance,which is roughly 1-1. we can do fine at 2-1.
we can probably even do ok at 3-1. but, guess what? the modern american diet, which is riddled with fast food, and processed food, and grain-fed meat... you see the ratio there? 17-1! things are way out of balance. it's very heavily inflammatory.
it's very heavily depressant. that suggests to us, of course,that if we could supplement with omega-3s, that might just be antidepressant. guess what? over a dozen controlled research trialshave now shown this to be the case. what's the anti-depressant dose, and i'll leave you with this,hopefully, important tip. the best research suggeststhat there's a specific omega-3 molecule that's called epa.
and at a dose, this is a pretty high dose, of 1,000-2,000 mg per day, it's shown to be antidepressant. many of our patientshave benefited remarkably, not just with respect to their depression, but other inflammatory conditions as well. my own story, when i begansupplementing with omega-3s, several years ago, the tendinitis in my knees went away,
and i could start runningfull court basketball again. the dryness in my eyes cleared up, and i could keep wearing my contacts. it's remarkably health promoting, in many different ways. now, for those of youwho want to get more details about this treatment program, i'm just going to zip ahead, because i'm out of time.
there's a lot more to share with you. i don't really talk about cows. we are designed as a very social species. we're designed to connect. did you know that face-time, time in the physical presenceof our loved ones, actually puts the breakson our stress response? did you know that our ancestorsspent all day, every day, in the companyof their loved ones?
their friends? think about the extent of face-time they shared with the peoplethat mattered most, and what have we done? we've traded face-time for screen-time. face-time for facebook, is that better? and the result is devastating. the result is devastating. we're born to connect.we need that connection.
in our treatment protocolwe work very, very hard to help each depressed individual resist the urge to withdraw. because, when you're ill,your body tells you to shut down and pull away. when you're physically ill with the flu, that's adaptive. when you have clinical depression, it's the worst thingin the world you can do.
even though every fiber of your beingis telling you exactly the opposite. we've got lots of good dataon our outcomes and, as i've said, they've exceededour wildest expectations. most of the patients that have come to us have tried meds, and they haven't gotten well. most of them have triedtraditional therapy, and it hasn't been the answer. the majority have gotten well,
as they have been willingto change the way they live. we had a man, a year and a half ago, who had been fightingdepression for 41 years. consecutively. and it was oneof the happiest days of my life when he came into a session, after 14 weeks, and he looked around the roomwith tears in his eyes, and said, "this is what i rememberedit felt like, to be free." it can happen!
now, we're still workingto improve this program. we're still working to make it better. i wish i had time to share with you some of the things we're learning. for those of you who wantto learn more about it, i'd invite you to go to our website. we have lots of details. i wish you alla joyful and depression-free life. thank you.
(applause)