What is public health psychology?

Public health psychology is a social science focused on improving the health and wellbeing of whole populations. It does this by investigating the links between human psychology and public health to create better health outcomes for populations, or sub-populations, of people. 

It’s one of the newest fields of public health, which focuses on keeping people healthy and safe through things like hygiene campaigns, preventative medicine, and sanitation. Public health psychology actually occurs at the intersection between public health and:

• health psychology, which is the discipline that works to understand how psychological and behavioural factors can contribute to physical health and illnesses. For example, societal stigma or personal health beliefs about mental health may prevent people from seeking treatment for mental illnesses like depression or anxiety.
• community health psychology, which is similar to public health psychology, but targets smaller groups or communities. For example, community health psychology interventions and initiatives might include working with schools to promote healthy eating among school-age children as a means of tackling obesity.
• clinical psychology, which oversees mental and behavioural health care for individuals. According to the British Psychological Society (BPS), it can help treat addiction, anxiety, depression, learning difficulties, and relationship issues.
• clinical health psychology, which explores the relationship between mental and physical health. According to the American Psychological Association (APA), it can help with tobacco use, weight management, pain management, psychological adjustments to chronic diseases, and adherence to medical treatment.
• social psychology, which studies how people’s thoughts, feelings and beliefs are influenced by others.

By better understanding the major psychological factors that affect the health of specific populations, and harnessing their expertise in professional psychology, public health psychologists can better understand the connection between human behaviour and public health issues that affect entire populations.

How do psychological factors, thought processes, and social influences affect a population’s health? And what is their role in diseases and illnesses? What are the biological factors that help determine the choices people make about their health, or about treating illnesses? These are the questions that public health psychologists work to answer.

What do public health psychologists do?

Because public health psychologists look at health at a population level, rather than at an individual level, their work tends to look at big-picture problems in health and illnesses. For example, professionals working in public health psychology may:

• collect, analyse, and interpret healthcare data and statistics at a regional, national, or international level.
• write and present reports to government bodies or large-scale institutions such as the World Health Organization or the United Nations.
• conduct new academic research (both qualitative and quantitative) for non-profit organisations or universities. For example, this research could include investigations into the causes of specific health problems, effective prevention measures, and relevant public health campaigns. It could also work to better understand the psychological or behavioural factors that can determine how people respond to particular health issues or illnesses. 
• work directly in a healthcare setting, such as a hospital or clinic, to design and promote prevention programmes, or unpick the psychological factors at play within health issues among specific or at-risk populations of people. This type of clinical work might include performing behaviour assessments and clinical interviews to better understand the health issues or illnesses affecting population health among a specific community of people.
• influence public policy makers, politicians, educators, and care providers towards adopting new public health legislation, laws, initiatives, or interventions. This work can include lobbying, or taking on the role of a consultant or adviser.

Initiatives in public health psychology

There are a number of prominent healthcare issues that public health psychologists are working to tackle through research, interventions, initiatives, and so on.

Because public health psychologists look at public health at a population level, they’re a huge asset to epidemiology. This branch of medicine:

• studies the distribution, patterns, and determinants of diseases in populations
• identifies the risk factors for disease
• shapes policy and practice around diseases in an effort to prevent and control them.

This work is significant. Chronic diseases, or non-communicable diseases, are the leading causes of illness and death. In fact, according to the World Health Organization, they cause 38 million deaths annually, with 80% occurring in low-income and middle-income countries. It further predicts that deaths from non-communicable diseases will increase by 17% over the next 10 years.

All of this means it’s imperative that public health psychologists focus on the link between behaviour and emotional factors and illnesses. Public health psychology research can directly inform health programmes and health policy at various levels. And this work is crucial in creating and promoting prevention programmes that effectively target some of the most urgent issues in healthcare today, including: 

• Cardiovascular disease (CVD). This can include heart disease, stroke, and other conditions affecting the heart or blood vessels – and it’s one of public health’s most significant challenges. A key way of preventing cardiovascular disease is through reducing the risk factors associated with it. For example, smoking is a big risk factor for CVD, so smoking cessation is key. For public health psychologists, preventing tobacco addiction among adolescents is an important initiative. By better understanding the psychological reasons why teenage populations start smoking, they can create more effective prevention campaigns to tackle the issue and promote better health behaviour.
• Type 2 diabetes. Type 2 diabetes is often linked by inactivity, so public health psychology can play a huge role in creating a behaviour change to increase physical activity among at-risk populations. For example, Diabetes UK says that at-risk groups include white people over the age of 40, and African-Caribbean, Black African, or South Asian people over the age of 25.
• Cancer. A cancer diagnosis can be incredibly stressful and upsetting for people. And at this time of high anxiety, people are required to participate in important decision-making conversations about their treatment and options. Psychological interventions can be life-changing for people with cancer during this time. Additionally, public health psychology research and initiatives can better equip health services and healthcare professionals to have these important – but difficult – conversations, foster better psychological health, and provide more effective social support that’s attuned to the type of cancer a person has, and the community to which they belong. For example, psychological care for a 60-year-old man diagnosed with prostate cancer is likely to differ from the psychological care for a 35-year-old mother of two who has been diagnosed with breast cancer.
• Degenerative diseases. Degenerative diseases occur when there are continuous degenerative cell changes that affect tissues or organs. They include Alzheimer’s disease, cystic fibrosis, multiple sclerosis, Parkinson’s disease, osteoporosis, and many others. Causes vary among the diseases, but can include ageing, genetics, viruses, or can be hereditary. They can also be more prevalent among particular populations. This is why health education and certain kinds of health promotion can be key in early detection of degenerative diseases, which in turn can help treat them more effectively.

Another significant research area for public health psychologists is the link between chronic diseases and socioeconomic factors and inequalities within populations. For example, how does poverty within a low-income population influence the psychology of the population – and how, in turn, do those psychological factors contribute to, for instance, heart disease?

Change health outcomes for whole populations of people

Public health psychology can help entire populations of people live healthier lives. By better understanding human behaviour, we can ensure that healthcare policies and practices are tailormade to be as effective as possible. And if this is a topic that interests you, the psychology of public health is a key component of the MSc Psychology at the University of Sunderland.

This flexible master’s degree is ideal for aspiring leaders and career-switchers from a range of backgrounds. It’s also studied 100% online, so you can learn around your current work and personal commitments.