Suicide is a complex public health problem driven by a multitude of biopsychosocial factors and is the result of gene–environment interactions. Psychosocial variables like chronic stress and trauma have biologic ramifications and can contribute to various forms of pathophysiology, dysregulation, and degradation, represented by allostatic load (AL). AL is the wear and tear that stress exerts on the body, and it has been associated with mental health problems and suicide. Fortunately, there are pharmacological and non-pharmacological interventions that may be effective at reducing AL and reversing its effects. Incorporating AL into efforts to promote early risk identification, prevention, and treatment of suicide is an important consideration. Critical next steps are identifying which AL biomarkers are most malleable, which effective treatments reduce AL, and if these reductions of AL are associated with decreased suicide.

With an understanding of the factors that may drive or protect against suicide and how they interact with physiological systems, we now turn to a discussion of what is known about suicide generally in the United States, specifically among various demographic groups. Suicide claimed 45,979 American lives in 2020, and US suicide rates have, until recently, increased while any other countries’ rates decreased. This chapter highlights what is known about the demographics of suicide in terms of age, race and ethnicity, sex, sexual orientation, and gender identity, as well as geography and location. We also highlight the limitations of this knowledge given that many diverse subgroups are aggregated into higher-order categories, small sample sizes limit knowledge of certain groups, and that many intersecting identities have been overlooked. While a single chapter is unable to cover all aspects of intersecting identities, attempts are made to highlight how intersections and multiple marginalization can compound suicide risk.

This chapter summarizes an optimistic perspective of the progress that has been made and what is known about suicide, while highlighting the questions that remain. We point out that many traditional understandings of suicide focus on risk factors, problems, and deficits and suggest there may be a role of more positive constructs, such as resilience, optimism, hope, gratitude, and others. We discuss the potential role of resilience – at the individual, community, and societal levels – in reducing suicide, and how positive psychology can inform suicide prevention efforts. Interventions to build psychological capital, resilience, personal strengths, or community empowerment may be beneficial. Indeed, positive suicidology, and even critical suicidology to a certain extent, attempt to incorporate these aspects.

The book concludes on a positive and action-oriented note. We highlight the role of hope in our society and how it can benefit suicide prevention efforts. The chapter summarizes how the book has accomplished three aims: (1) providing a biopsychosocial perspective on suicide and prevention, (2) serving as a public health intervention by increasing awareness, de-bunking myths, and destigmatizing suicide, and (3) helping readers shift to a perspective of hope and optimism. Capitalizing on this optimism, the chapter then focuses on increasing agency and offering concrete action steps, such that the reader feels they can be part of suicide prevention.

This chapter shifts from discussing whether or not suicide is moral to a focus on the theories of why suicide occurs. Focusing on the eighteenth century to the present, this chapter summarizes several theories of suicide and how they uniquely frame various aspects of pain and suffering that lead to suicide. These theories vary in terms of how they attribute suicide to individual and/or societal causes, with more psychodynamic approaches locating the source of suicide in internal psychological drives and sociological perspectives, like Durkheim’s, highlighting the role of societal regulation and integration as drivers of suicide. Current theories highlight the mechanisms of ideation-to-action, and how one progresses from thinking about suicide to acting on such thoughts. This segues into a discussion of the risk factors that drive suicide risk (e.g., family history, trauma, mental illness, and social isolation) as well as factors that may buffer against suicide risk (access to mental health care, coping skills, and safe environments).

Building on our understanding of how suicide emerges and for whom in the United States this occurs, we move into discussions of identification of and intervention for those at risk. The chapter begins with a brief overview of screening to identify those at risk of suicide, and the challenges in the research literature. Comprehensive risk assessments that incorporate multiple sources of information remain essential, and there is a potential role for machine learning in this process. We then summarize biologic (e.g., lithium, electroconvulsive therapy) and psychosocial (e.g., safety planning, cognitive behavioral therapy) promising practices in suicide prevention, as well as the potential role of technology (e.g., telehealth, apps) in suicide interventions. We then highlight community-based interventions (e.g., gatekeeper training, lethal means safety) and the evidence supporting them. At the societal level, state and federal efforts have focused on creating safe environments (e.g., legislation to reduce access to means) and providing economic supports that are promising. Given the complexity of suicide, we highlight the potential benefits of multimodal, multilevel intervention programs.

Suicide has long been a topic of social discourse, with pendulating views of the phenomenon. This chapter highlights how social, cultural, and religious views on the morality of suicide shifted over time and discusses today’s current understanding of suicide as a public health crisis. Early documentations of suicide highlight it as a means by which to avoid becoming a spoil of war or avoiding dishonor. With the rise of Christianity, suicide came to be viewed as a mortal sin, one that could result in the punishment of surviving family members. Perspectives on the morality of suicide have vacillated over time, with current times viewing suicide not as an issue of morality but as a public health issue. Despite years of suicide prevention efforts, suicide rates in the United States have generally remained stubborn. Given the complex nature of suicide, it will likely require integrated interventions and resources that cross clinical and community realms.

The chapter will describe a pragmatist view of habit formation and of learning or inquiry. Indeed, one essential function of the brain is the formation of habits to suit contexts. Another major function of cephalic (mind, brain, body, world) sensibility is maintaining them. Habit formation in our species is tied to learning and inquiry; habit stability is mediated across the brain and continuous with the ecological/social milieu we are living in. There is a continuous thread between what is in the brain/body and what is not, in the neural organization of habits. The thread is quite permeable. Habits are sustained, or not, by the niche they are sculpted in, and evolve in or not.