Stress affects up to 90% of people, and we know it harms our mental and physical well-being.
Stress can impact the activity and function of our genes. It does this through “epigenetic” changes, which turn certain genes on and off, although it doesn’t change the DNA code.
But why do some people react less well to stress, while others seem to cope with the pressure?
Social support means having a network to turn to when needed. It can come from natural sources such as family, friends, partners, pets, coworkers, and community groups. Or from formal sources such as mental health specialists.
My new study, published today in the Journal of Psychiatric Research, shows for the first time that these positive effects are also observed on human genes.
Having supportive social structures dampens and even reverses some of the damaging effects of stress on our genes and our health, via the process of epigenetics.
The results suggest that the DNA we are born with is not necessarily our destiny.
Read more: How chronic stress changes the brain – and what you can do to reverse the damage
What is epigenetics
Our genes and our environment contribute to our health.
We inherit our DNA code from our parents, and this does not change over the course of our lives. Genetics is the study of how the DNA code acts as a risk or protective factor for a particular trait or disease.
Epigenetics is an extra layer of instructions on top of DNA that determines how they affect the body. This layer can chemically modify DNA, without changing the DNA code.
The epigenetic term is derived from the Greek word “epi” which means “above, above”.
Read more: Explanator: what is epigenetics?
This extra layer of information sits on top of the genes and surrounding DNA. It acts like a switch, turning genes on or off, which can also impact our health.
Epigenetic changes occur throughout our lives due to different environmental factors such as stress, exercise, diet, alcohol and drugs.
For example, chronic stress can impact our genes via epigenetic changes which in turn can increase the rate of mental health disorders like post-traumatic stress disorder (PTSD), depression and anxiety.
New technologies now allow researchers to take a biological sample from a person (such as blood or saliva) and measure epigenetics to better understand how our genes respond to different environments.
Measuring epigenetics at different times allows us to better understand which genes are changed due to a particular environment.
Read more: Extreme stress in childhood is toxic to your DNA
What did we study?
My studies studied the positive and negative factors that determine a person’s response to stress and how this changes the epigenetic profiles of genes.
Certain groups of people are more likely to face stress in the course of their routine work, such as first responders, medical workers and police.
So my research team and I recruited 40 Australian first year paramedic students at two specific times – before and after exposure to a potentially stressful event. The students provided saliva samples for DNA and completed questionnaires detailing their lifestyle and health at both times.
We studied epigenetic changes before and after exposure to stress, to better understand:
We found that stress influenced epigenetics, which in turn led to increased rates of distress, anxiety, and depressive symptoms in participants.
However, students who reported high levels of perceived social support showed lower levels of stress-related health outcomes.
Students with a strong sense of belonging to a group, organization or community coped with stress much better and had fewer negative health outcomes after being exposed to stress.
These two groups of students showed fewer epigenetic changes in genes that were changed due to stress.
COVID has made us more isolated
The COVID pandemic has placed great psychological and emotional burdens on people due to uncertainty, altered routines and financial pressures.
In Australia, rates of anxiety, depression and suicide have skyrocketed since the start of the pandemic. One in five Australians reported high levels of psychological distress.
The pandemic has also made us more isolated and our relationships more distant, which has a profound impact on social bonds and belonging.
My study highlights how family and community support, and a sense of belonging, influence our genes and act as a protective factor against the effects of stress.
In these unprecedented and stressful times, it is vital that we build and maintain strong social structures that contribute to good physical and mental well-being.