Mental health

Lane Kenworthy, The Good Society
August 2019

Mental illness is pervasive. Approximately 50% of Americans will experience a mental disorder at some point in their life, and about 10% of children and 20% of adults suffer from mental ill-health at any given moment in time. The same is true in other rich democratic nations.1 As figure 1 suggests, mental illness is more common than heart disease, cancer, and diabetes.

Figure 1. Lifetime incidence
Share of the US population. Data source: Centers for Disease Control (CDC).

Mental ill-health also is varied, and it comes at all stages of life. The American Psychiatric Association’s Diagnostic and Statistical Manual (DSM) currently lists about 300 mental disorders. In early childhood, as the brain is developing, there is attention deficit/hyperactivity disorder (ADHD), conduct disorder, and others. Onset of anxiety, schizophrenia, and bipolar disorder most commonly occurs in adolescence and young adulthood. The average age at which depression appears is 30. Dementia usually begins in old age.

What are the main types of mental ill-health? How common are they? What are their consequences? Have we made progress in provision of effective treatment and care? How can we do better?

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Mental illness comes in many forms. In gauging its prevalence, researchers use multiple indicators, including diagnoses by mental health professionals, surveys, and medication prescriptions. None of these is as precise as the signals that exist for many types of physical afflictions.

ADHD is excessive or long-lasting trouble paying attention, difficulty controlling impulsive behaviors, or being overly active. It is diagnosed in about 10% of American children, according to estimates from parent surveys.2

Anxiety is the most common mental health problem, affecting an estimated 18% of American adults. Anxiety takes various forms.3

  • Generalized anxiety disorder. This affects about 3% of American adults. It tends to manifest in worry, difficulty concentrating, motor tension (fidgeting, headaches, trembling), inability to relax, autonomic overactivity (lightheadedness, sweating, dizziness), and/or difficulty sleeping.
  • Panic disorder. The incidence is about 3%. “People having panic attacks believe they are going to die, or faint, or have a heart attack, or a stroke, or go mad. They experience some bodily sensation which they believe is a signal of danger. This sets off their ‘fight or flight’ mechanism and their heart races…. People with such fears are often unable to leave the house for fear of what might happen.”
  • Social anxiety disorder. 7%. This typically begins around age 13. Persons with social anxiety disorder “believe other people will think them boring or inept. They constantly monitor the impression they are making on people, and this self-consciousness makes things even worse. They often blush, sweat, or shake. When things get bad enough they just hide.”
  • Phobias. 9%. The average age of onset is 7.
  • Obsessive compulsive disorder (OCD) is “a chronic and long-lasting disorder in which a person has uncontrollable, reoccurring thoughts (obsessions) and behaviors (compulsions) that he or she feels the urge to repeat over and over.” 1%. Average age of onset is 19.
  • Post-traumatic stress disorder (PTSD). 3.5%. PTSD can affect persons who have had “a specific shock which constantly recurs in their thoughts or which is brought back by some experience or other. Such people typically become highly sensitive, jumpy, and irritable, in a way that can cripple relationships at home and at work.”

Depression is a sad mood or loss of interest in important parts of life that interferes with normal, everyday functioning and persists for more than a short time. Depression tends to manifest in one or more of the following: reduced concentration and attention, disturbed sleep, diminished appetite, reduced self-esteem and self-confidence, ideas of guilt and unworthiness, bleak and pessimistic views of the future, ideas or acts of self-harm or suicide.4

Depression seldom begins until the teens, and the average age of onset is 30. Often there is no clear or obvious trigger.

Figure 2 shows the share of people who self-report being depressed in the past year. These data are available only for European nations and so don’t include the US. The share ranges from a low of 5% in Italy to 12% in Ireland and Portugal. Estimates for the US suggest that 6% to 8% of Americans are depressed in any given two-week period and about 17% will have depression at some point in their life.5

Figure 2. Depression
Share of the population with depression in the past 12 months. Self-reported. 2014. Data source: OECD, Health at a Glance 2017, figure 13.7, appendix, using Eurostat data. “Asl” is Australia; “Aus” is Austria.

Bipolar disorder is characterized by repeated episodes in which a person’s mood and activity levels “are significantly disturbed, this disturbance consisting on some occasions of an elevation of mood and increased energy and activity (mania or hypomania), and on others of a lowering of mood and decreased energy and activity (depression). Recovery is usually complete between episodes.”6 Estimates by the Global Burden of Disease Collaborative Network suggest that, in most countries, the incidence of bipolar disorder is between 0.3% and 1.2% of the population.7 In the United States, the National Institute of Mental Health puts the incidence among the adult population at 2.8%.8

Schizophrenia is one of the most problematic mental disorders. When active, its symptoms can include delusions, hallucinations, trouble with thinking and concentration, and lack of motivation.9 The incidence of schizophrenia in most countries is 0.2% to 0.4% of the population, according to the best available data.10

Personality disorder affects approximately 1% of the population. “People with personality disorder include two main groups. The first are people with highly unstable lives and feelings. Many of them self-harm…. Their condition is known, somewhat oddly, as Borderline Personality Disorder…. The second group have Anti-Social Personality Disorder. These people regularly violate the normal rights of other people. They are often charming, and many of them are psychopathic in the sense that they have no sense of guilt and no remorse.”11

Eating disorders. An estimated 0.1% to 1% of the population in rich democratic nations suffers from anorexia (deliberate undereating to achieve low weight) or bulimia (preoccupation with control of body weight, including taking extreme measures to exert such control).12 Other eating disorders may affect a larger share, but we lack good data.

Substance abuse disorders. Dependence on alcohol or drugs often co-occurs with other types of mental ill-health, but we have limited understanding of which tends to cause which. In the United States, approximately 6% of the population are dependent on alcohol, and about 0.5% are judged to be severely dependent. About 1% are dependent on hard drugs such as heroin and cocaine.13

Dementia afflicts approximately 1% of Americans. The most common form, accounting for three-fifths of cases, is Alzheimers. As we see in figure 3, the incidence of dementia is lower in the US than in most other affluent democratic countries. However, the smaller share in the US is due partly, perhaps mainly, to lower life expectancy here, as figure 4 suggests. The risk of dementia doubles every five years after age 65, so the longer people live, the larger the share who will end up with dementia.14

Figure 3. Dementia
Share of the population. 2017. Data source: OECD, Health at a Glance 2017, figure 11.9. “Asl” is Australia; “Aus” is Austria.

Figure 4. Life expectancy and dementia
Dementia: share of the population. 2017. Life expectancy: years at birth. 2014. Data source: OECD. “Asl” is Australia; “Aus” is Austria. The line is a linear regression line. The correlation is +.48.


Has depression increased, as headlines occasionally claim? Two studies examined depression in rural counties in Canada and Sweden over a significant portion of the twentieth century. Neither found evidence of a change.15 A continuous time series of depression among American college students found an increase between 1950 and 1990 and then no further change.16 The increase could be due to the massive expansion in the share, and type, of Americans going to college during that period. Other studies have concluded that since 1980 there may have been a decrease in depression among teenagers and college students.17

Like depression, anxiety too may have increased among US college students between 1952 and 1993. But it then leveled off.18 Studies of high school students and adults from the 1970s through the 2010s find no evidence of an increase.19

A meta-analysis found no evidence of an increase in depression or anxiety in Austria, Germany, Switzerland, and the United Kingdom between the mid-1960s and 2015.20

Dementia appears to have decreased since 1995 in the United States and Europe. The likelihood that a 75-year-old man will develop dementia, for example, fell from 25% in 1995 to 18% today. This decline doesn’t appear to hold in Asia or South America.21

For other mental health conditions, we don’t know, as there are no comparable long-run data.


When untreated or treated ineffectively, mental illness causes pain and suffering. It can also result in inability to participate fully in society, in physical health problems, and in early death.

Unhappiness. According to calculations by Richard Layard and colleagues, in the affluent nations for which good data are available — the US, UK, Australia, and Germany — mental health problems are the single largest contributor to misery (very low life satisfaction). They are more influential than physical health problems, low income, low education, unemployment, marital status, gender, or age.22

Depression, anxiety, and other mental disorders reduce a person’s subjective well-being directly. In the words of J.K. Rowling, author of the Harry Potter books, “Depression is the most unpleasant thing I have ever experienced…. It is that absence of being able to envisage that you will ever be cheerful again. The absence of hope.”23 And here is how Charles Walker, a member of parliament in the UK, described his experience with obsessive-compulsive disorder24:

“Over the past thirty-one years OCD has played a fairly significant part in my life. On occasions it is manageable and on occasions it becomes quite difficult. It takes one to some quite dark places. I operate to the rule of four, so I have to do everything in evens. I have to wash my hands four times and I have to go in and out of a room four times. My wife and children often say I resemble an extra from Riverdance as I bounce in and out of a room, switching lights off four times. Woe betide me if I switch off a light five times because then I have to do it another three times. Counting becomes very important. I leave crisp and biscuit packets around the house because if I go near a bin, I have to wash my hands on numerous occasions.

OCD is like someone inside one’s head banging away. One is constantly striking deals with oneself. Sometimes these are quite ridiculous and on some occasions they can be rather depressing and serious. I have been pretty healthy for five years, but just when you let your guard down, this aggressive friend comes and smacks you right in the face. I was on holiday recently and I took a beautiful photograph of my son carrying a fishing rod. I was glowing with pride and then the voice started, ‘If you don’t get rid of that photograph, your child will die.’ You fight those voices for a couple or three hours, and you know that you really should not give into them because they should not be there and it ain’t going to happen. But in the end, you ain’t going to risk your child, so one gives in to the voices and then feels pretty miserable about life.”

Mental health problems also can cause unhappiness indirectly, via stigma, rejection, isolation, mistreatment, and abuse.25

Physical health problems. Mental illness causes chronic stress, which is bad for the body. It heightens inflammation. It slows recovery from physical illness and injury. Mental disorders also tend to increase unhealthy behaviors such as smoking, drinking, and poor diet.

In addition, people with mental health problems are less likely to get treated for physical health maladies. One reason is that they are less likely to seek treatment. Another is that health providers may treat them differently. According to Dhruv Khullar, “For doctors, two related biases are probably at play. The first is therapeutic pessimism. Clinicians, including mental health professionals, often hold gloomy views about whether patients with serious mental illness can get better. This can lead to a resigned passivity, meaning that certain tests and treatments aren’t offered or pursued…. The second is a concept called diagnostic overshadowing, by which patients’ physical symptoms are attributed to their mental illness. When doctors know a patient has depression, for example, they’re less likely to think her headache or abdominal pain portends a serious illness.”26

Disability. Mental illness accounts for a significant share of disability. In rich democratic countries, about one-third of people receiving disability benefits do so because of a mental health problem. Mental disorders account for about one-third of the number of years that people, worldwide, live with disability (YLDs). And they are estimated to reduce disability-adjusted years of life expectancy (DALYs) by 13% to 23%.27

Early death. In the US, persons with depression, bipolar disorder, and other serious mental illnesses live, on average, 15 to 30 years less than those without mental illness. This gap in life expectancy is larger than the gap for race, ethnicity, geography, or socioeconomic status.28 Depression reduces life expectancy by as much as smoking.29

One reason for the shorter lifespan of persons with mental illness is that, as just noted, it tends to adversely affect physical health.

Another reason is suicide. Americans with depression are about 12 times as likely as others to commit suicide. Persons with bipolar disorder or schizophrenia are about 20-25 times more likely.30 An estimated 90% of people who kill themselves are mentally ill when they do so. Of these 90%, 60% have depression, 10% personality disorder, 10% bipolar disorder, and 10% schizophrenia.31 In the United States, suicides get far less attention than murders, yet they are about three times as common. Around 45,000 Americans kill themselves each year.

Figure 5 shows the rate of suicide in the world’s rich democratic nations since 1960. In the US, the rate was flat from 1960 through the early 1980s, then dropped slightly for the following two decades. Since 2000 it has increased, and it’s now back to the same level as half a century ago.

The average among this set of countries as a whole rose from 15 in the 1960s to 17 in the 1980s. By the 2010s it had dropped to 12. (This excludes South Korea, which has data only since 1985.) Much of the progress occurred in a group of mostly European nations — Austria, Belgium, Denmark, Finland, France, Sweden, and Switzerland, along with Japan — that had comparatively high rates through the 1980s but have achieved significant declines since then.

Figure 5. Suicides
Per 100,000 population. Data source: OECD. Thick line: US. “Asl” is Australia; “Aus” is Austria.

Figure 6 shows trends over the past 100 to 150 years in three countries for which good estimates are available that far back in time. In England, the suicide rate peaked in the early 1930s and is considerably lower now. The same is true of Switzerland since 1980. In the United States there has been fluctuation over time but no systematic trend either up or down.

Figure 6. Suicides
Per 100,000 population. Data source: Steven Pinker, Enlightenment Now, 2018, figure 18.3, using data from various sources.

Violence and crime. It’s estimated that one-third of men who are violent to their partners or spouses have mental health problems. In Britain, 90% of men who end up in prison have such problems.32

Financial cost. Mental illness imposes financial costs in a variety of ways: less employment, more time away from work, less productive work, greater disruption in school and work, more crime, greater physical health care provision. Richard Layard and David Clark estimate that the total cost to a typical rich nation is about 7% of GDP. In comparison, hardly any nation spends more than 1% of GDP on treatment of mental ill-health.


Since the late 1800s, progress in preventing and treating physical ailments has been stunning. One indicator is the spectacular rise in life expectancy in the world’s rich democratic nations, from about 35 years in 1880 to 80 years today.

For mental health the story is far less encouraging, though also less clearcut. There was little if any progress in the late 1800s and the first half of the twentieth century. New procedures and techniques — insulin coma therapy, electric shock therapy, lobotomy, Freudian uncovering of unconscious memories, and more — burst onto the scene with high hopes and praise but turned out to have little or no evidentiary support.33 In the assessment of some, the story since then is essentially the same: no real progress.34 Proponents of this view tend to offer four pieces of argument and evidence.35

First, mental health providers’ (particularly psychiatrists’) shift from a focus on psychotherapy to a biology-centered view of the causes of mental illness hasn’t yielded much in the way of gains. According to Benedict Carey, “Over the past 40 years, [psychiatry] remade itself from the inside out, radically altering how researchers and the public talked about the root causes of persistent mental distress…. The arrival of biological psychiatry, in the past few decades, was expected to clarify matters, by detailing how abnormalities in the brain gave rise to all variety of mental distress…. The blueprint for reassembly was the revision in 1980 of psychiatry’s field guide, the Diagnostic and Statistical Manual of Mental Disorders, which effectively excluded psychological explanations. Gone was the rich Freudian language about hidden conflicts, along with the empty theories about incorrect or insufficient ‘mothering’…. But despite billions of dollars in research funding, and thousands of journal articles, biological psychiatry has given doctors and patients little of practical value, never mind a cause or a cure.”36

Second, progress skeptics contend there has been little advance in pharmacological treatment of mental health problems. Despite an explosion of new pharmaceuticals designed to treat specific types of mental illness, particularly since the 1990s, the results, in this view, have been underwhelming. In the assessment of Edmund Higgins, “drugs developed in the past 20 years perform like older medications. Abilify is no more effective for treating schizophrenia than the very first antipsychotic, Thorazine. New antidepressants lift mood no better than the tricyclic antidepressants discovered in the 1950s. Lithium, first used in 1949, remains the gold standard for bipolar disorder. Adderall provides no further advantages for attention-deficit/hyperactivity disorder than the Benzedrine first administered for it in 1937. There are exceptions — we appear to be better at treating the depressive phase of bipolar disorder, and Clozaril is a more effective treatment for schizophrenia than its predecessors — but much of what seemed so revolutionary 20 years ago was more illusion than substance. The new medications tap into the same brain mechanisms as the old ones, albeit with fewer side effects. Finding novel treatments for mental illness has become so discouraging that several pharmaceutical companies have shut down or reduced neuroscience research.”37

Third, “The most discouraging assessment came in 2013 from an in-depth analysis by the U.S. Burden of Disease Collaborators. Hundreds of investigators gathered data on 291 diseases and injuries between 1990 and 2010. Combining premature death and disability to calculate the burden of each disease, they found that the toll of mental disorders had grown in the past two decades, even as other serious conditions became more manageable.”38 We don’t, however, know whether this finding owes to a genuine increase in the harm caused by mental illness or to the fact that a larger number of harmful conditions are now classified as mental illness due to a broadening of diagnostic criteria.

Fourth, suicide hasn’t decreased in the US (figures 5 and 6 above).

What is the case for progress? It points to the following.39

First, stigma seems to have decreased. This owes in part to publicity and to greater attention in key institutions such as schools and workplaces. Another reason is the growing perception that mental ill-health is treatable. Richard Layard and David Clark point out that this has precedents: “When cancer was largely untreatable, people hid it. Only as it has become treatable have people talked about their condition. And the fear and dread have been greatly reduced. Likewise, as more and more disabilities have become treatable, people have become much more open and straightforward about their disability. So have their families. And they have often formed themselves into extremely effective lobby groups.”40

Second, access to mental health care very likely has increased, though we don’t have hard data to be sure. Figure 7 shows the rate of service use for people with anxiety, mood, and substance abuse disorders in nine affluent democratic nations as of the mid-2000s. These numbers are lower than we’d like, but they almost certainly are higher than in earlier decades.

Figure 7. Persons with anxiety, mood, or substance abuse disorders receiving treatment
Share of persons. Data source: P.S. Wang et al, “Use of Mental Health Services for Anxiety, Mood, and Substance Disorders in 17 Countries in the WHO World Mental Health Surveys,” The Lancet, 2007.

Third, some modern medicines help to alleviate pain and suffering. For anxiety disorders and major depression, drugs lead to recovery in more than 50% of cases, though only with continued use.41 And while the more recent wave beginning in the 1990s — particularly antidepressants such as Prozac — haven’t proved more effective in treatment, they tend to have fewer side effects, they allow for greater experimentation in dosage, and they are less harmful in cases of overdose. Those are meaningful improvements.42

Fourth, there has been significant advance in treatment via therapy.43

“In the 1960s and 1970s came major breakthroughs in psychological therapy. The most important of these was what is now called Cognitive Behavioural Therapy (CBT), which relies on the fact that thoughts affect feelings, and that good mental habits can be systematically built up step by step. CBT is certainly not the only therapy which works, and it does not always work. But it has been evaluated so much more often than any other therapy that we can speak with certainty about its average overall effects. These have now been established in hundreds of randomized clinical trials of exactly the same kind as are used in testing any medical treatment.

The general finding is that around 50% of people treated with CBT for depression or anxiety conditions recover during treatment, and many others improve significantly. For depression, CBT is as effective as drugs in the short run, and more effective in preventing the recurrence of depression down the road. For anxiety, CBT is even more impressive. Many people with conditions like social phobia, panic disorder, or obsessive–compulsive disorder have had their condition for decades, but if successfully treated they are mostly cured for life.”

Fifth, while suicide hasn’t decreased in the United States, it has fallen significantly since the 1980s in about half of the world’s rich democratic nations (figure 5 above).


For several millennia, perhaps longer, medical researchers, mental health practitioners, philosophers, and others have been searching for ways to reduce the incidence, severity, and impact of mental disorders.44 There has been progress, but far less than most would wish. The main reason why progress has been limited is that we haven’t discovered the causes of many types of mental ill-health.

Despite our continued ignorance, we do now have a range of prevention and treatment strategies supported by evidence. So while there is much yet to learn, there are ways we can help right now. This is especially true since perhaps the major failing on mental health, even in the world’s affluent democratic nations, isn’t lack of knowledge but rather lack of treatment. The best available data suggest that only one in three persons with mental illness currently gets treated.45

So what should we do?

Research on neurological processes and their interaction with life. Progress will accelerate when we have a better grasp of the causes of mental disorders. Where should researchers aim their attention? In recent decades, as was true also a century ago, the focus has been on biology. It’s possible this will turn out to be the key. Yet it also might not. Benedict Carey puts the case for skepticism as follows46:

“Although there are several important exceptions, measurable differences in brain biology appear to contribute only a fraction of added risk for developing persistent mental problems. Genetic inheritance surely plays a role, but it falls well short of a stand-alone ’cause’ in most people who receive a diagnosis. The remainder of the risk is supplied by experience: the messy combination of trauma, substance use, loss, and identity crises that make up an individual’s intimate, personal history. Biology has nothing to say about those factors.”

Andrew Scull offers a similar take47:

“Much as psychiatry (and many of those who suffer from mental disorders) might wish it otherwise, madness remains an enigma, a mystery we seemingly cannot solve. Its depredations remain something we can at best palliate. Over the past half century, the expansion of neuroscience has been remarkable, and its discoveries legion. Unfortunately, none of them have proved of much clinical use to date in the treatment of mental illness. Nor have neuroscientists as yet uncovered the etiological roots of madness….

We are still waiting for those mysterious and long-rumored neuropathological causes of mental illness to surface. It has been a long wait, and on more than one level a misguided one, I think, if the expectation is that the ultimate explanation of madness lies here and only here. Why is that? It makes no sense to regard the brain (as biological reductionists do) as an asocial or a pre-social organ, because in important respects its very structure and functioning are a product of the social environment. For the most remarkable feature of the human brain is how deeply and profoundly sensitive it is to psychosocial and sensory inputs….

To an extent unprecedented in any other part of the animal kingdom, humans’ brains continue to develop post-natally, and the environmental elements that most powerfully affect the structure and functioning of these brains are themselves a human creation….

The very shape of the brain, the neural connections that develop and that constitute the physical underpinnings of our emotions and cognition, are profoundly influenced by social stimulation, and by the cultural and especially the familial environment within which these developments take place….

Somewhere in that murky mix of biology and the social lie the roots of madness.”

Institutionalization? Deinstitutionalization? In the 1950s, there were roughly 500,000 Americans, about 0.3% of the population, in state mental hospitals and asylums. Conditions in these hospitals, brought to popular attention by the movie One Flew Over the Cuckoo’s Nest, could be dismal. And by the early 1960s a new movement among psychiatrists contended that early intervention, alteration of the social environment, and effective use new antipsychotic medications such as Thorazine would allow such persons to live in the community with outpatient treatment. The federal government commenced to close many of the state mental hospitals and replace them with a network of community mental health centers. A 1975 Supreme Court decision affirmed this trend, ruling that the mentally ill had a right “to live in the least restrictive setting necessary for their well-being.” Today about 35,000 Americans, 0.01% of the population, remain in state hospitals or asylums.

Deinstitutionalization, however, failed to produce effective living conditions or treatment for many people with serious mental health problems. A significant number of those who were released in the 1960s and 1970s ended up homeless, in nursing homes, or in prison.48 And the community mental health centers tended to treat mainly people with “social maladjustment or no mental disorder” rather than those with serious mental illness, according to data collected by the National Institute of Mental Health.49

Medication. Pharmaceuticals aimed at alleviating the symptoms of mental illness began to proliferate in the middle of the twentieth century, particularly in the United States. In the 1950s, Miltown, a calming drug, was taken by about 5% of American adults, mostly for anxiety. In 1973, reportedly the year of peak prescription, more than 25% took a psychotherapeutic medication. Currently about 10% take an antidepressant such as Prozac. Around 5% of American children take an ADHD medication such as Ritalin.50

The benefits of such medications are sometimes overstated and adverse side effects underplayed. And yet, as noted earlier, for anxiety disorders and major depression, drugs lead to recovery in more than 50% of cases, albeit only with continued use. The biggest problem isn’t that medications don’t help, though that is true for some persons, but rather that they aren’t accessible for many with mental disorders, that for some people their side effects offset or outweigh their benefits, and that some have trouble continuing to take them for more than a short period.51

Continued efforts to develop pharmaceutical palliatives will be one element of a humane approach to improving the treatment of mental illness. Just as important is getting the medications to people who need them and providing support necessary to ensure their effective and ongoing use.

Early intervention. Many types of mental illness can be improved if diagnosed and treated early. Good mental health in the early years of life is correlated with good mental health later in the life course. Half of those with mental health problems experience onset by age 15. Policy can help via support for mothers during pregnancy, support for parents in the years following birth, and extra support for parents and children in high risk groups.52

Therapy. Cognitive behavioral therapy (CBT) is one of the major advances in treatment of mental illness. Its effectiveness for a range of mental health problems has been established via randomized controlled trials. It has been found to be at least as effective as medication for treating anxiety and depression. And unlike medication, in many instances CBT does not require continued expense; most people need no more than 14 to 20 sessions.53

For many people, however, the cost currently is too high and availability too low. In the United States, two-thirds of primary care physicians say they can’t get outpatient services for their clients who have mental health problems.54 Assuming cognitive behavioral therapy continues to yield good results, it should be made much more broadly accessible.

Adaptation of institutions. Schools can do better at fostering good mental health and treating mental health problems. A recent study finds that effective school practices include focusing on positive mental health, teaching skills, integrating mental health training into the school curriculum, regular contact with parents, and following these practices throughout elementary and secondary schooling.55

Workplaces can, at a minimum, foster greater awareness of and support for mental ill-health among both employees and managers. Even better are formal programs to assess risk of stress and other conditions and to enhance management of them via workload adjustment, flexible hours, counseling, or other mechanisms. In Finland, employers are required to identify and address risks to workers’ mental well-being.56

Involuntary nonemployment appears to be a key contributor to anxiety and depression. Active labor market programs, which help people move more quickly and effectively back into work after they lose a job, are therefore a useful tool in improving mental health.57

Loneliness and social isolation contribute to depression. They become increasingly likely as people age, because fewer family and friends are still alive. Elder care programs that provide assistance at home or in an institutional setting may improve mental health not only by assisting with assorted tasks but also by providing in-person contact. Japan’s government has paid to train more than 5 million volunteers to offer respite to dementia sufferers and their carers and to watch out for “wanderers.”58

Providers of physical health care also can improve their treatment of patients with mental health challenges. Experiments with alternative methods that focus on the particular needs of patients with serious mental health issues — specialized training in after-care, follow-ups at home, and more — have yielded promising results.59

Suicide prevention. Keys here include “restricting access to lethal means; awareness raising programs for young people in school; the use of drug and psychological therapies; taking action to provide information and signposting, as well as physical barriers, in suicide hotspots; and reducing risk of subsequent suicidal events through psychosocial assessment upon presentation to hospital followed by cognitive behavioral therapy.”60


Mental illness, especially anxiety and depression, affects about half of Americans at some point in their lives. For those with serious afflictions, and for some with more moderate or even mild mental disorders, the consequences can be severe. Mental ill-health is the biggest known contributor to unhappiness, it increases disability, and it contributes to early death.

We have made progress in treatment of mental illness, though experts disagree about how much. In prevention there has been little, if any, advance.

While big gains may not come until the causes of mental disorders are better understood, we can, even with our current limited knowledge, make lives better for a significant number of people with mental ill-health. Particularly valuable would be improved access to cognitive behavioral therapy and medications.

  1. National Institute for Mental Health (NIMH), “Mental Illness”; H.U. Wittchen et al, “The Size and Burden of Mental Disorders and Other Disorders of the Brain in Europe 2010,” European Neuropsychopharmacology, 2011; Richard Layard and David M. Clark, Thrive: How Better Mental Health Care Transforms Lives and Saves Money, Princeton University Press, 2015; OECD, Health at a Glance 2017, p. 60. 
  2. Centers for Disease Control (CDC), “Attention-Deficit/Hyperactivity Disorder” and “What Is ADHD?” 
  3. World Health Organization (WHO), International Classification of Diseases (ICD-10); Anxiety and Depression Association of America, “Facts and Statistics,” using data from the National Institute of Mental Health; Layard and Clark, Thrive, ch. 2. 
  4. CDC, “Mental Health Conditions: Depression and Anxiety”; WHO, “Depression.” 
  5. R.C. Kessler, P. Berglund, O. Demler, R. Jin, K.R. Merikangas, and E.E. Walters, “Lifetime Prevalence and Age-of-Onset Distributions of DSM-IV Disorders in the National Comorbidity Survey Replication,” Archives of General Psychiatry, 2005; Laura A. Pratt and Debra J. Brody, “Depression in the US Household Population, 2009-2012,” Data Brief 172, National Center for Health Statistics, 2014; Substance Abuse and Mental Health Services Administration, “Results from the 2013 National Survey on Drug Use and Health: Mental Health Findings,” Center for Behavioral Health Statistics and Quality, US Department of Health and Human Services, 2014; WHO, “Depression and Other Common Mental Disorders: Global Health Estimates,” 2017; Debra J. Brody, Laura A. Pratt, and Jeffery P. Hughes, “Prevalence of Depression Among Adults Aged 20 and Over: United States, 2013–2016,” Data Brief 303, National Center for Health Statistics, 2018. 
  6. WHO, International Classification of Diseases (ICD-10). 
  7. Global Burden of Disease Collaborative Network. 
  8. NIMH, “Bipolar Disorder.” 
  9. The standard requirement for a schizophrenia diagnosis is that “a minimum of one very clear symptom (and usually two or more if less clear-cut) belonging to any one of the groups listed as (a) to (d) below, or symptoms from at least two of the groups referred to as (e) to (h), should have been clearly present for most of the time during a period of 1 month or more: (a) thought echo, thought insertion or withdrawal, and thought broadcasting; (b) delusions of control, influence, or passivity, clearly referred to body or limb movements or specific thoughts, actions, or sensations; delusional perception; (c) hallucinatory voices giving a running commentary on the patient’s behaviour, or discussing the patient among themselves, or other types of hallucinatory voices coming from some part of the body; (d) persistent delusions of other kinds that are culturally inappropriate and completely impossible, such as religious or political identity, or superhuman powers and abilities (e.g. being able to control the weather, or being in communication with aliens from another world); (e) persistent hallucinations in any modality, when accompanied either by fleeting or half-formed delusions without clear affective content, or by persistent over-valued ideas, or when occurring every day for weeks or months on end; (f) breaks or interpolations in the train of thought, resulting in incoherence or irrelevant speech, or neologisms; (g) catatonic behavior, such as excitement, posturing, or waxy flexibility, negativism, mutism, and stupor; (h) ‘negative’ symptoms such as marked apathy, paucity of speech, and blunting or incongruity of emotional responses, usually resulting in social withdrawal and lowering of social performance; it must be clear that these are not due to depression or to neuroleptic medication; (i) a significant and consistent change in the overall quality of some aspects of personal behaviour, manifest as loss of interest, aimlessness, idleness, a self-absorbed attitude, and social withdrawal.” WHO, International Classification of Diseases (ICD-10). 
  10. Global Burden of Disease Collaborative Network; NIMH, “Schizophrenia.” 
  11. Layard and Clark, Thrive, p. 34. 
  12. Global Burden of Disease Collaborative Network. 
  13. Layard and Clark, Thrive, ch. 2. 
  14. OECD, Health at a Glance 2017, figure 11.10; The Economist, “Special Report: Dementia,” August 29, 2020. 
  15. Cited in Steven Pinker, Enlightenment Now, 2018, p. 282. 
  16. J.M. Twenge, B. Gentile, C.N. DeWall, D. Ma, K. Lacefield, and D.R. Schurtz, D. R., “Birth Cohort Increases in Psychopathology Among Young Americans, 1938–2007: A Cross-Temporal Meta-Analysis of the MMPI,” Clinical Psychology Review, 2010; Layard and Clark, Thrive, ch. 3. 
  17. J.M. Twenge and S. Nolen-Hoeksema, “Age, Gender, Race, Socioeconomic Status, and Birth Cohort Differences on the Children’s Depression Inventory: A Meta-Analysis,” Journal of Abnormal Psychology, 2002; J.M. Twenge, “Time Period and Birth Cohort Differences in Depressive Symptoms in the US, 1982–2013,” Social Indicators Research, 2014. 
  18. Twenge, “Time Period and Birth Cohort Differences in Depressive Symptoms”; Twenge et al, “Birth Cohort Increases in Psychopathology Among Young Americans”; J.C. Sage, Birth Cohort Changes in Anxiety from 1993–2006: A Cross-Temporal Meta-Analysis, Master’s Thesis, San Diego State University, 2010. 
  19. K.H. Trzesniewski and M.B. Donnellan, “Rethinking ‘Generation Me’: A Study of Cohort Effects from 1976–2006,” Perspectives on Psychological Science, 2010; A. Terracciano, “Secular Trends and Personality: Perspectives from Longitudinal and Cross-Cultural Studies,” Perspectives in Psychological Science, 2010. 
  20. Jan Schürmann and Jürgen Margraf, “Age of Anxiety and Depression Revisited: A Meta-Analysis of Two European Community Samples (1964-2015),” International Journal of Clinical and Health Psychology, 2020. 
  21. Frank J. Wolters et al, “Twenty-Seven-Year Time Trends in Dementia Incidence in Europe and the United States,” Neurology, 2020. 
  22. Richard Layard, Dan Chisholm, Vikram Patel, and Shekhar Saxena, “Mental Illness and Unhappiness,” in World Happiness Report 2013, UN Sustainable Development Solutions Network, 2013; Layard and Clark, Thrive, ch. 5; Andrew E. Clark, Sarah Flèche, Richard Layard, Nattavudh Powdthavee, and George Ward, “The Key Determinants of Happiness and Misery,” World Happiness Report 2017, UN Sustainable Development Solutions Network, 2017. 
  23. Quoted in Layard and Clark, Thrive, p. 19. 
  24. Quoted in Layard and Clark, Thrive, pp. 67-68. 
  25. WHO, “10 Facts on Mental Health.” See also Stephen P. Hinshaw and Andrea Stier, “Stigma as Related to Mental Health Disorders,” Annual Review of Clinical Psychology, 2008. 
  26. Layard and Clark, Thrive, ch. 5; Dhruv Khullar, “The Largest Health Disparity We Don’t Talk About,” New York Times, 2018. 
  27. Layard et al, “Mental Illness and Unhappiness,” p. 45; Daniel Vigo, Graham Thornicroft, and Rifat Atun, “Estimating the True Global Burden of Mental Illness,” The Lancet: Psychiatry, 2016; WHO, “10 Facts on Mental Health.” 
  28. Khullar, “The Largest Health Disparity We Don’t Talk About.” 
  29. Layard and Clark, Thrive, ch. 5. 
  30. Jennifer M. Boggs et al, “General Medical, Mental Health, and Demographic Risk Factors Associated With Suicide by Firearm Compared With Other Means,” Psychiatric Services, 2018; Deborah M. Stone et al, “Vital Signs: Trends in State Suicide Rates — United States, 1999-2016 and Circumstances Contributing to Suicide — 27 States, 2015,” Morbidity and Mortality Weekly Report, CDC, 2018. 
  31. Layard and Clark, Thrive, pp. 51-53. 
  32. Layard and Clark, Thrive, pp. 83-84. 
  33. Andrew Scull, Madness in Civilization: A Cultural History of Insanity, from the Bible to Freud, from the Madhouse to Modern Medicine, Princeton University Press, 2015. 
  34. Scull, Madness in Civilization, especially ch. 12; Edmund S. Higgins, “Is Mental Health Declining in the US?,” Scientific American, 2017. 
  35. A fifth is that disability awards for mental disorders have dramatically increased since 1980. But this probably owes mainly to the fact that only in 1984 did mental ill-health become a valid condition for eligibility. 
  36. Benedict Carey, “When Will We Solve Mental Illness?,” New York Times, 2018. 
  37. Higgins, “Is Mental Health Declining in the US?” 
  38. Higgins, “Is Mental Health Declining in the US?” 
  39. See especially Layard et al, “Mental Illness and Unhappiness”; Layard and Clark, Thrive; Clark et al, “The Key Determinants of Happiness and Misery.” 
  40. Layard and Clark, Thrive, p. 64. 
  41. Layard et al, “Mental Illness and Unhappiness”; Layard and Clark, Thrive, ch. 8; Peter D. Kramer, Ordinarily Well, Farrar, Straus and Giroux, 2016. 
  42. Kramer, Ordinarily Well, chs. 17, 19. 
  43. Layard and Clark, Thrive, pp. 9-10. 
  44. Scull, Madness in Civilization. 
  45. Layard and Clark, Thrive, ch. 1. 
  46. Carey, “When Will We Solve Mental Illness?” 
  47. Scull, Madness in Civilization, pp. 409-411. See also Layard and Clark, Thrive, ch. 7. 
  48. Susan Sheehan, Is There No Place on Earth for Me?, Vintage, 1981; Christopher Jencks, The Homeless, Harvard University Press, 1994; E. Fuller Torrey, American Psychosis, Oxford University Press, 2013; The Economist, “Special Report: Mental Illness,” 2015; Treatment Advocacy Center, “Serious Mental Illness (SMI) Prevalence in Jails and Prisons,” 2016; Bruce Western, Homeward, Russell Sage Foundation, 2018, p. 49. 
  49. Richard A. Friedman, “A Solution That Now Looks Crazy,” New York Times, 2014. 
  50. Layard and Clark, Thrive; Scull, Madness in Civilization; Kramer, Ordinarily Well; CDC, “Attention-Deficit/Hyperactivity Disorder.” 
  51. Layard et al, “Mental Illness and Unhappiness.” 
  52. Layard et al, “Mental Illness and Unhappiness”; The Economist, “Special Report: Mental Illness”; Layard and Clark, Thrive; David McDaid, Emily Hewlett, and A-La Park, “Understanding Effective Approaches to Promoting Mental Health and Preventing Mental Illness,” OECD Health Working Paper 97, 2017. 
  53. Layard and Clark, Thrive, especially ch. 8. 
  54. Layard and Clark, Thrive, p. 59. 
  55. McDaid et al, “Understanding Effective Approaches.” 
  56. McDaid et al, “Understanding Effective Approaches.” 
  57. McDaid et al, “Understanding Effective Approaches.” 
  58. The Economist, “Special Report: Mental Illness.” 
  59. Khullar, “The Largest Health Disparity We Don’t Talk About.” 
  60. McDaid et al, “Understanding Effective Approaches.”