Happiness and Health in Psychiatry: What Are Their Implications?

Background: Happiness is a lasting state and is associated with the absence of negative emotions, the presence of positive emotions, life satisfaction, social engagement and objectives in life. Researchers have demonstrated the benefits of happiness in many aspects of life, but few studies have been conducted within psychiatry. Objectives: To develop a critical literature review of studies on happiness and health in order to bring some further and useful information to psychiatry updating the article " Happiness: a review " published in 2007 in Revista de Psiquiatria Clínica. Methods: Computational searching was undertaken of digital data basis (PubMed and SciELO) using the keywords " happiness " and " health ". One hundred twenty-seven papers published between 2004 and 2014 were found, but only 76 had the keywords in the title or abstract and with this were selected. Results: Personality traits, such as self-direction; being married; being involved in physical and leisure activities; higher educational backgrounds and intelligence quotient; religiosity, volunteering and altruism; good physical and mental health; were positively related to happiness. Discussion: Analysis of the concept of happiness and its associated emotions may be more complex than describing the symptoms of psychiatric disorders. Despite this, the study of happiness brings several positive implications for psychiatry.


Introduction
Happiness is the main objective of human existence 1 .According to many authorities including Greek philosopher Aristotle, all human behavior aims to achieve happiness 2,3 .However, Seneca pointed out that reaching happiness is a challenging task, since it is difficult to find what makes life happy; and, many times, the more happiness is searched for, more elusive it becomes 4 .In this sense, Socrates explained to Fedro that reflection about the truth would nourish the soul; whereas philosophy would be the adequate tool to achieve this goal 5 .
Happiness was first investigated as an object of philosophical study.Only in the middle of the last century some empirical studies within the health and associated fields of knowledge started to appear 6,7 .For this reason, the World Health Organization (WHO) has included and emphasized happiness as an important factor within the concept of health 1,8,9 .Most studies on happiness are in the field of psychology 10 and economics 10,11 .In psychology, for example, the concept of positive psychology has emerged 12,13 ; according to Seligman (2011), this is an area that studies what is right in humans as their positive attributes, that is, their active psychological characteristics and strengths.Positive psychology advocates that promoting mental health involves the promotion of psychological resources, improving the quality of life and preventing mental disorders, especially those disorders that have a strong environmental burden, thereby promoting happiness.Thus, the contributions of positive psychology can and should be considered by psychiatric clinicians and those in general medicine 15,16 .
In this context, happiness can be defined as a fundamental emotion characterized as a lasting state which is combined with: (i) the absence of negative emotions; (ii) the presence of positive emotions; (iii) life satisfaction; (iv) social engagement and (v) objectives in life 8,[17][18][19] .Another concept that has been largely used for defining happiness within the specialized literature is subjective well-being 6,8,13,19 .
It is relevant to mention that the concept of quality of life is a broader terminology, also involving happiness itself 19 .
In order to use a holistic approach to promote health (i.e., taking into account all factors that influence health), it is important to understand how a healthy person behaves and how positive emotions can contribute to this process.In this sense, as proposed by Seligman  (2011), treatment is not just fixing what is broken; rather, it involves nurturing what is best within ourselves 19 .Undoubtedly, the actual psychiatric medical model that mainly focuses on the diagnosis and treatment of mental disorders, has been immensely helpful to many patients; nevertheless, it is believed that it is necessary to move forwards, and this will bring benefits to all, including those with a psychiatric diagnosis 15 .
Based on this, the main goal of this paper is to conduct a critical literature review concerning happiness and health which may be useful for the expansion of psychiatric practice, and also to update the article published in 2007 in the Revista de Psiquiatria Clínica titled "Happiness: a review" 18 .

Methods
Computer searches were carried out within the PubMed data basis, using the keywords "happiness" and "health", during August, 2014; and in the SciELO data basis with the same keywords during November, 2014.Filters were applied, requiring that the keywords appeared in the title or abstract and that the articles had been published between September 2004 and February 2014.From the PubMed, initially 80 papers were related to this topic.After a preliminary analysis, ten papers were excluded from this sample because of the following reasons: (i) four did not cite the word happiness either in their titles or in their abstracts; (ii) two concerned topics only related to, but did not directly concern, happiness and health; (iii) four were informative articles (Figure 1).Regarding the SciELO data basis, 47 papers were found; however, only six contained the word happiness in their titles and/or abstracts.
In addition to these searches, another was performed using the reference lists of the papers already selected.This was rewarding in allowing us to identify the classic work provided by significant authors in this field, such as Martin Seligman, Robert Clonniger anda Ruut Veenhoven, as well as the importance in this context of the WHO (Table 1).Based on the results from these searches, it was possible to identify six core aspects related to the keywords "happiness" and "health", namely: 1. Aspects of happiness; 2. Biology of happiness; 3. Psychology of happiness; 4. Sociodemography of happiness; 5. Health, mental health and happiness; 6. Positive implications for psychiatry.Each of these aspects is described further in the following section.

Aspects of happiness
The scientific literature often refers to two types of happiness: psychological well-being and hedonic well-being.The term psychological well-being, or eudaimonia, has been used to refer to a combination of character strengths involving self-direction (e.g., autonomy, purpose of life, environmental and self-acceptance), cooperatives (i.e., positive relationships with others) and self-transcendence (i.e., personal growth and self-realization) 8,12 .Hedonic well-being, or hedonia, is associated with: (i) a pleasurable life; (ii) life satisfaction; (iii) presence of positive feelings and (iv) absence of negative feelings 20 .It can be said, therefore, that psychological well-being is connected to the personal fulfillment of one's own potential, while hedonic well-being is linked to the experience of satisfaction.Although these are two different ways to experience happiness, they are strongly related 8,12,20 .However, from a historical point of view, they have different origins.Aristotle postulated that every human being had unique capabilities, called daimon, that should be recognized and developed 3 .Similar to this idea are the concepts/ theories of: (i) self-actualization, described by Maslow; (ii) the individualization theory developed by Jung; and (iii) Antonovsky's theory of existential coherence; all are related to the concept of eudaimonia 20,21 .It is relevant to note that Epicurus provided the basis for the later development of hedonism 20 .The biological differences between each type are discussed further below.
Besides these two types of happiness, it is important to distinguish two types of emotions or affects that are connected to the understanding of happiness: positive affect and negative affect.These are independent variables and may or may not be in opposition 18 ; it is possible to feel positive and negative emotions at the same time, as well as being in a neutral state.These emotions/affects might seem to have different determinants, consequences and correlations 14 , and it is relevant to note that happiness itself is related to the frequency of positive emotions and not to their intensity 14,18 .Negative emotions, such as fear and anger, are recognizably beneficial as they help people to ensure their survival and safety.Nevertheless, these are short-term benefits; the Broaden and Build Theory states that positive emotions amplify cognition and behavior, providing intellectual, social and physical resources for optimum performance.Thus, the long term benefits of positive emotions contribute to the individual's ability to continue his/her development 14 .

Biology of happiness
Trying to understand the complex link between psychological factors and biological change, scientists have studied the effects on health of negative emotions.For example, it is known that stress, depression and anxiety generate changes in the hypothalamic-pituitary-adrenal axis, with a consequent increase of cortisol, sympathetic stimulation and elevation of proinflammatory markers.If these negative stimuli persist, the risk increases of developing cardiovascular disease, cancer and/or infections 22,23 .However, only recently has scientific interest focused on verifying that positive emotions could also induce biological changes.Some studies have demonstrated that the two types of happiness (eudaimonia and hedonia) can cause biological changes that promote positive emotions 24 ; however, most of this research has shown that only eudaimonia is statistically related to biological changes 12,20,22 .In general, the changes found in the neuroendocrine, immune and cardiovascular systems secondary to positive emotions are beneficial and protective effect 12,23 .
First, positive emotions can quickly cancel the adverse effects of body stress reaction, and thus return the body to a steady state 14 .It may be interesting to see how this biological characteristic of positive emotions corresponds to the observation that many people say they feel good, even through times of suffering, if adverse events are interpreted as having a purpose or meaning 8 .Perhaps this search for meaning is a psychic attempt to maintain an emotional balance.
Second, higher levels of eudaimonia are related to lower levels of salivary cortisol and proinflammatory cytokines, a lower cardiovascular disease risk, longer duration of REM sleep 20,23 , higher levels of immunoglobulin A, and higher HDL cholesterol levels 12 compared to those with low levels of eudaimonia.There are, however, differences between men and women in this regard; for example, inflammatory markers such as C-reactive protein and fibrinogen are lower in happy women than in happy men 24 .
These alterations have been found regardless of the presence of negative emotions, suggesting that happiness has a direct effect on the body, regardless of the absence of negative affect 23 .On the other hand, in the same manner as tobacco and some physical leisure activities are found in stressed individuals, depression and anxiety and their associated behaviors contribute to increased rates of diseases and adverse biological changes; part of the positive biological findings in happy individuals is also due to their tendency towards healthier habits and more prudent lifestyles 23 .
Another important point is that studies of monozygotic twins, separated and raised in different environments, have shown that happiness has a genetic component of 35%-50% in humans 6,14,25 .In this regard, it is suggested that the long allele of the promoter region of the 5-HTT gene (5-HTTLPR long) could be associated with optimism.The 5-HTT gene encodes serotonin transporters; this type of polymorphism in the promoter region is called a functional polymorphism 26 .De Neve found that individuals satisfied or very satisfied with life have a statistically significant higher percentage of this genotype (long 5-HTTLPR homozygous), compared to people dissatisfied with life.Recently, it was discovered that, in women, a low MAO gene expression is significantly associated with increased levels of happiness.This finding, however, was not present in men 26 .
It is important to consider that many of these studies have some limitations such as small sample sizes, cross-sectional designs or bivariate analyses.Still, the studies are promising and already point us in several directions.

Psychology of happiness
If 35%-50% of happiness depends on a genetic influence, at least 30%-40% are represented other variables, suggesting that the environment and life events also have a large influence on subjective well-being.However, this influence varies from event to event; personal interpretations may be the key to understanding the link between life events and subjective well-being 6 .In this sense, character has a strong impact on the perception of all aspects of health, including physical, social and emotional well-being.For example, self-direction is measured by levels of responsibility, ingenuity and ability to find meaning, and has a strong connection with all aspects of health.Changes in selfdirection explain about 32% of the variations in the risk of disease and about 45% of the variations in subjective well-being.
The way in which an individual sees life can predict his/her health outcomes.For example, pessimists need to visit four times as many doctors in one year than optimists 17 .Similarly, the link between success and happiness exists not only because success makes people happy, but because positive attitudes engender success 27 .A concept that may explain these relationships is emotional competence (EC), also known as emotional intelligence.This concept relates to how the individual deals with emotional information, intrapersonally and interpersonally.High EC is associated with greater happiness, and higher mental and physical health, greater professional success and greater satisfaction in social relationships and marriage 28 .
Christakis and Fowler used the Framingham study to try to answer the following question: can the happiness of others influence personal happiness?The study was based on the theory that emotional states can be transferred interpersonally through mimicry, by copying emotionally relevant bodily actions, especially facial expressions, and it concluded positively.The authors suggested that happiness may be seen as a network phenomenon; happiness clusters resulted from the spread of happiness and not only by the tendency of people to associate with similar individuals 29 .Although this theory of social contagion has also been replicated in disorders such as depression, a study involving roommates in college resulted in different findings, arguing that happiness and mental disorders have low social contagion 30 .Perhaps the last word on the subject has not yet been given, but there is no doubt that this is an exciting area.

Sociodemography of happiness
Several factors associated with happiness have been studied.Below we describe some that appear in more recent studies and have not been reported in other review articles on happiness.

Economic factors
The first modern economist to study happiness found a paradox (i.e., the Easterlin paradox) in which groups of richer countries are happier than groups of poorer countries, but this difference is not so clear between rich and Latin American countries where there are larger social differences.Even in poor countries, the relationship between money and happiness is not linear.Deprivation and poverty are less associated with happiness 31 however, after reaching a level of care that meets basic needs, other factors, such as people's increased aspirations and concerns about their own heritage come into play 10,32 .Indeed, despite the economic changes, happiness levels have remained relatively stable in countries such as Ireland and the United States 17,33 ; a study linking retirement and welfare showed that monetary gain increased financial well-being, but the benefits of retirement on health and subjective and social welfare were transient 34 .Another binding factor between economic issues and happiness seems to be social inequality, since individuals living in areas of great social inequality tend to describe themselves as unhappy and unhealthy 35 .From the individual point of view, however, people who are paid by the hour appear to be happier 36 .In addition, informal workers tend to report higher levels of happiness related to their professional activity 37 .Another factor that may explain this lack of linearity between economic issues and subjective well-being levels is that happy people tend to focus more on social ideals and moral goals than just monetary achievement 7 .

Age
With increasing age, happiness tends to decrease in the population as a whole 38,39 .However, from the individual point of view, centenarians who have high levels of satisfaction with their lives in the past tend in their old age to make the best personal assessments of their own health, economic security and happiness 40 .Therefore, there is a protective relationship between happiness and physical decline that occurs in old age 41,42 .In this age group, contentment related to the children and the health of the family is associated with a higher level of happiness 43 .Moreover, happiness is related to longevity, independent of family genetic and environmental issues 44 .Finally, a rather curious result was obtained from a longitudinal study that found a positive association between chocolate consumption, optimism, better health and greater psychological well-being 45 .

Interpersonal relationships
People living in minority groups tend to report less happiness than those who belong to majority groups 7 .For example, after the tragic events of September 11, 2001 in the United States, Arab Americans reported a greater perception of abuse and discrimination; this perception was related to higher levels of psychological stress, worse health outcomes and a lower sense of happiness 46 .
Married people tend to experience better health and happiness than unmarried people.This relationship has been found in various countries, within various health parameters and in both men and women 47 .This association, however, extends beyond marital status, because the quality of marriage also has a great influence on it [47][48][49] .There is also a positive relationship between happiness and sexual satisfaction in women and men, although that relationship is stronger in women 50 .

Religiosity and volunteering
It is well established that people who identify themselves as religious tend to report better health and more happiness, regardless of their religious affiliation, performance of the religious activities, work, family, social support or financial situation 51 .The studies that have reached these conclusions were mostly carried out in the western population.However, research on Islamic and Egyptian students also found a positive relationship between religious affiliation and happiness [52][53][54] .Seen as human dimensions by many researchers, these aspects tend to be increasingly taken into consideration in the treatment and development of people 15,55 , especially considering that the humans are religious beings, since they spend more time praying than having sex 15 .
Another related aspect is the issue of volunteering and altruism.People who engage in volunteer work and altruistic behaviors tend to be healthier, live longer, and to be happier [56][57][58] .However, when this type of activity becomes too arduous, occupying more than 11 hours per week, the happiness levels tend to decrease 56,58 .

Educational level, sports and leisure
The positive relationship has long been recognized between education levels, intelligence quotient (IQ) and health levels.More recently, a positive relationship has also been found between educational levels, IQ and the happiness index 10,59,60 .
Other factors studied in recent years include physical leisure activities that have been shown to increase subjective well being, both in the short and long term 61 .Involvement in sport also appears to have a causal relationship with higher levels of happiness 62 .
Finally, it is worth remembering the psychological theory of the set point of happiness, according to which people have a basal level of happiness that they tend to return to over time, even after major events such as winning the lottery or divorce.However, unemployment is one of the events that has a negative impact on happiness that people tend not to adapt to 10 .

Health, mental health and happiness
Happiness and health are closely related, both on an individual and population basis; happier people and communities tend to be healthier, and the inverse relationship is also true 63 .This relationship was also found in adolescents 64 , the young 65,66 and the elderly 67 .However, in the elderly, a study found that health predicted subjective well-being, but the reverse was not true 68 , perhaps because, in this population, other factors previously listed in the sociodemography of happiness subsection 3,4 came into play.As examples, the happiest nations tend to have lower levels of blood pressure 69 ; a study of coronary artery disease (CAD) found that optimistic men had a lower risk of developing CAD 17 ; and happier people recovered better from sickness 70 .
It is well known that chronic diseases are associated with negative impacts on various aspects of the quality of life, including happiness, and increase the risk of depression 71 .However, different chronic diseases seem to impact differently on subjective well-being 71 .In the elderly, for example, the physical diseases that impose decreased happiness were disabling pain and urinary incontinence; these disturb the activities of daily living and are associated with social stigmas 67 .
Furthermore, mental disorders in general, and specifically depression, alcohol and drug abuse 72 and anxiety 72,73 more negatively affect happiness than does physical illness.Similarly, there is an inverse relationship between suicide and the subjective well-being index, and also between the presence of mental disorders and happiness 74 .For this reason, it has been proposed that happiness indices could be used as population markers for mental disorders 74 .In this sense, the ability to exercise control over adaptive negative emotions is associated with beneficial results in mental health 75 .However, excessively large or small variations in positive emotions are associated with poorer mental health, particularly depression and anxiety disorders, lower life satisfaction and more unhappiness 76 .Perhaps this issue of emotional control can also explain the association between mental disorders and unhappiness, and the large presence of negative emotions that mental disorders cause.

Positive implications for psychiatry
Given all of the above, a question must be raised: is possible and is it desirable to promote happiness?The evidence appears to say yes.Happiness does not cure the disease but makes people less sick and the size of this effect appears to be comparable to smoking or not 77 .In mental health, in particular, the study of factors that lead to happiness can be particularly beneficial in those at higher risk of developing mental disorders 18 .In fact, positive psychological interventions have already been successfully tested in patients with depressive disorders 78 .Furthermore, investment in approaches that increase subjective well-being may be cheaper for the public purse.For example, a study comparing psychotherapy versus paying monetary damages in legal compensation cases showed that psychological approaches may be up to 32 times cheaper than financial compensation, as well as being more effective in promoting health and happiness in patients potentially involved in litigation 79 .The understanding of what promotes happiness in people can also be useful for mental health professionals themselves since they are at risk of decreased life satisfaction and burnout syndrome; this can have negative consequences for psychiatric patients, since high levels of stress in these professionals predict therapeutic problems in general 80 .
Positive psychology contains the concept of flourish.This concept suggests five features found in happy people (PERMA) that should be promoted to increase levels of subjective well-being in people in general: 1. Positive emotions (P) 2. Engagement (E; being in the flow) 3. Relationships (R; having healthy relationships) 4. Meaning (M; purpose in life) 5. Accomplishment (A) Investment in any of these areas promotes the others and helps develop happiness 81,82 .
In addition to increasing happiness, feeding positive emotions such as gratitude, kindness, perseverance, optimism and creativity, contributes to increased resilience, buffers psychological stress and promotes mental health.Programs such as the Penn Resiliency Program (PRP), developed for this purpose, have been successfully implemented in the United States, the United Kingdom, Australia, Portugal and China.In this program, participants learn to adopt more optimistic explanatory styles, detecting inaccurate thoughts, challenging negative beliefs and considering alternative interpretations.In addition, a task force made up of several positive psychology professionals developed an inventory to help people identify their character strengths; this is called the Values in Action Inventory of Strengths (VIA-IS).Despite its limitation of being based on selfreport, the simple application of this instrument has been shown to be therapeutic in itself and has brought positive results.The VIA -IS and the PRP are intended for use by adults and children.There is also a tool named Appreciative Inquiry, used in institutions, that aligns with positive psychology.By means of this instrument, groups are helped to refocus problems towards the identification of existing strengths in group members, thus providing a starting point for positive change 14 .

Discussion
We have critically reviewed the literature on the relationship between happiness and health in order to identify the most relevant information for psychiatry.We especially considered data that were also being studied in the latest research, and not only the findings of classical studies.Studies are numerous; nevertheless, we realize that many studies on the topic of happiness are transversal; this, despite the use of large samples, diminishes the robustness of some conclusions.In addition, the measurement scales are often limited by being of the self-report variety.In a sense, we already find this difficulty in psychiatry itself in its use of subjective medical measurements, such as pain.However, analysis of the concept of happiness and its associated emotions may be more complex than describing the symptoms of psychiatric disorders, which can expose us to some difficult biases that are difficult to bypass.Another limitation of some studies seems to lie in their contained psychotherapeutic interventions.Although there are well-established interventions within positive psychology (some have been reported in this article) as well an interesting proposal for psychoeducation made by Clonniger (2006), progress in the expansion of clinical approaches seems to be necessary.In addition, most therapeutic interventions proposed have comprised a more psychoeducative approach.Certainly, some of these limitations exist because the interest of the health sciences in this topic is relatively recent.Moreover, is an area that is more linked to the formulation of psychotherapeutic approaches and this tends to discourage investment in the development of new psychoactive drugs.
The study of happiness from a scientific perspective, together with a realization of its implications for health is promising and fascinating, especially if we believe our medical indices of good health are not always in agreement with the perceptions of the patient or society.For example, consider the population of Matsigenka in the Peruvian Amazon; over the past 30 years health indicators have improved greatly, but during the same time period this population reported itself as sicker and unhappier 83 .Perhaps for similar reasons psychiatry has failed to increase subjective well-being in the general population, despite extensive pharmacological advances and new psychotherapeutic techniques.Probably, the focus has been almost exclusively pathological 15 .
The immediate goal of all medicine is to alleviate suffering.To achieve this in psychiatry, accurate diagnostic, psychopharmacological advances and psychotherapeutic techniques are fundamental.However, identify what makes life happy can be useful in various types of health prevention (primary, secondary and tertiary) 84 .This particularly applies to promoting mental health as specified in the WHO parameters: a state of well-being in which people can understand and use their own skills, deal with the stresses of life, work and love, and may contribute to their communities 8,9 .Furthermore, the promotion of mental health may contribute to reducing the stigma towards psychiatry and psychiatric patients 15 .

Conclusion
Positive emotions related to happiness generate beneficial alterations in the neuroendocrine, immune and cardiovascular systems.Aspects of character, such as self-direction, are strongly linked to higher levels of happiness.According to the Easterlin paradox, the relationship between money and happiness is not linear.Levels of happiness tend to fall with increasing age; however, the previous level of subjective well-being is a major predictor of happiness in this age group.Religious people who practice physical leisure activities, who have high educational levels or higher IQs, who are married, who are involved in sports, or do up to 11 hours of volunteer work per week tend to report higher levels of happiness.In addition, higher levels of happiness are related to lower physical and mental illness, as well better coping abilities in adversity For this reason, the study of happiness brings several positive implications for psychiatry that should be considered in clinical practice and in future research.

Table 1 .
Papers from 2013 to 2014 selected for this review