The five factors that play a role in mental illness

You might be curious about what causes mental illness. Just like any other illness, mental illness is not caused by just one or two things, but often occurs because of a combination of factors that are both genetic and environmental.

Everyone is unique, however everyone’s mental health is influenced differently by five factors:

• Genetics: the unique mixture of genes someone inherits from their parents
• Epigenetics: transgenerational influences, for example heritable traits that are passed from a grandparent to their grandchild
• Early environment: pre- and post-birth circumstances and stressors
• Current environment: the personal situation of the person, including all the elements such as family circumstances, social life, education, environment, financial and more
• Family pattern: the unique ways of managing that every family develops

It is a combination of these five factors that influence the development of mental illness.

These factors can be grouped into two categories:

• Environmental factors - such as what’s going on around us when we are growing up and into adulthood
• Biological factors - the coding in each of our cells that we are born with

How biological factors impact our mental health

Mental health is a complex area and although some research suggests that poor mental health runs in families, it is not the case that this will always happen.

Although epigenetics is a relatively new science, it often appears that the experiences of our parents or grandparents can be handed down through generations. This information is not exactly carried in your genes, but in other parts of our cells or through patterns of behaviour. However, the impact of this can be significantly affected by the environment that you grow up in.

Your own physical health also has an important role to play in your mental wellbeing, ranging from exercise to diet, smoking and drinking alcohol. For women, the menopause can also impact your mental health.  

How environmental factors impact our mental health

Events and the environment that you grow up in may contribute to poor mental health in later life. However, as an adult, your environment continues to play a key role in your mental health.

Social factors such as a lack of social support, discrimination, stress, unemployment, housing and poverty are all well-known factors that play a part in your mental health. Regardless of how well you think you are coping, if some of these factors are present, they are likely to affect how well you can cope with situations.

Major life events including bereavement, the breakup of a relationship, divorce, or moving house can put pressure on someone’s ability to cope. Even seemingly positive life events, such as a marriage of childbirth, can have the same effect and may increase your vulnerability to becoming unwell.

The Mental Health Foundation provides more information to help you learn more about the social, health and environmental factors that impact your mental health.

We're all unique

Some people may be more vulnerable than others to developing mental illness. However, in general, life events and your physical health play a major role in triggering this vulnerability. Given a certain kind of stress to a certain degree, everyone is susceptible to mental illness.

Everyone is unique. Even between brothers and sisters, your unique genetic makeup and lived experience if your own. Think of a family you know - the children might have very different personalities even though they grow up in the same household with the same parents.

The ability to cope with a stressor will vary from individual to individual and may be cumulative, in the same way that the ability to manage pain or physical illness is different for everyone. Having too much on your shoulders might severely impact your ability to cope. This is why it’s so important to seek out support, or to keep up hobbies, exercise, or activities that you enjoy.

Using stress as an example, it may also be the case that if you experience difficulties during childhood, this can affect your development and become a core part of the way that you process your experiences and affect your ability to ‘bounce back’ or overcome difficulties.

It’s important to remember that mental illness is a result of many factors, including inherited characteristics and life experiences. Whilst mental illness is not anyone’s fault, it's a good idea to learn about your own mind and the factors that affect you so that you learn to manage difficult emotions and ask for help when you need it.

What's next? Explore our Mental Health and Wellbeing Resources to learn more about your own mind or the mental illness of a parent, or ask for help if you want to speak to someone.