Footprints to Recovery

Close this search box.
Get Help Now!
Close this search box.

What Are the Underlying Causes of Mental Illness

Mental illness, or a mental health disorder, is a type of psychological syndrome or behavioral pattern that is associated with an increased risk of disability, suffering, pain, or loss of freedom to act independently. 

According to studies, more than 43 million people in this country suffer from some form of mental illness. Unfortunately, many of those people don’t get the proper help that they need, which can put a major strain on not only themselves but also family members and our society as a whole.

While there are still a lot of unknowns when it comes to mental illness, thanks to more and more time being dedicated to it in the scientific field, we have more answers than we ever have before when it comes to mental illness.

What Are the Underlying Causes of Mental Illness

Causes of Mental Illness

While there is a multitude of causes of mental illness, let’s focus on some of the bigger ones:

  • Substance Abuse
  • Brain Damage
  • Trauma
  • Infection
  • Malnutrition
  • Fetal Damage
  • Genetics

When it comes to what exactly causes mental illness, there isn’t just one thing, but a variety of factors. The brain is a very complex part of our body, and just the slightest imperfection can result in a variety of mental issues.

Substance Abuse

Substance abuse and mental health disorders tend to go hand-in-hand. When this happens, it is called a co-occuring disorder. As we mentioned earlier, there are over 40 million Americans who suffer from some sort of mental illness, and many people don’t get the proper help that they need. Instead, many people will turn to drugs or alcohol to self-medicate for their mental health issues instead of going to treatment. While it’s not nearly as common, in some situations, a substance abuse issue can end up causing a mental health issue as well.

Substance abuse can lead to a mental health disorder because prolonged substance abuse can have adverse effects on the brain and even completely change someone’s overall brain chemistry. As a result, this can cause reductions or increases in the structures of the brain that make up the affected systems. 

The chemical and physical disruption caused by drug abuse can result in mental illness. This is particularly true in people who are already at a high risk of mental health disorders. The substance abuse can actually lead to protective factors that may have kept the mental illness from manifesting originally to be diminished.

Brain Damage

Mental illness can be the direct result of any sort of brain damage or brain injury, whether this happened during the birthing process or as a result of some sort of physical injury. Brain damage has been shown to directly lead to mental health disorders such as OCD, depression, mania, PTSD, and psychosis. 

One of the more common brain injuries that can ultimately lead to mental health disorders are concussions. Given the nature of concussions and the effects on the brain, mental health issues may not be seen for a long time.


Trauma to the brain can be a major cause of mental illness. This doesn’t necessarily mean that the trauma has to be physical, either. Repeated mental trauma can also result in a mental health disorder.

This is especially true in children. Repeated trauma, especially early in life when the brain is in its most developmental state, can result in a change in the chemical makeup in the brain. The most common areas of the brain that are affected are the limbic system, the hypothalamus, pituitary, and adrenal systems, and the pleasure and reward systems.


There are certain infections that can have an adverse effect on the brain and its chemical makeup. This is especially true when it comes to certain bacterial infections. Children are more likely to develop a mental health disorder as a result of an infection. In one specific case, it has been shown that a strep infection in childhood can lead to a condition called PANDAS, or pediatric autoimmune neuropsychiatric disorder. PANDAS can manifest into a severe type of OCD.


We have always been told that a nutritious diet is crucial to our overall health and well-being. It’s also very crucial to the chemical balance in our brain. In fact, studies have shown that malnutrition, especially early in life, can cause damage to the brain and result in the development of a mental health issue. 

Fetal Damage

Sometimes a mental health disorder can develop before a person is even born. Use and abuse of drugs and/or alcohol by a woman while pregnant can lead to the child either being born with a mental health issue or developing one later in life. 

Depression and anxiety disorders are the most common mental health disorders that can be developed as a result of drugs and alcohol being used during pregnancy.

Another way in which a fetus can be affected is by an attack on the system of a pregnant woman, most commonly by some sort of infection. Studies have shown that if a woman’s immune system is attacked by a virus when pregnant, the chances that the baby will be born with a mental health issue increase. This is the result of the mother’s immune system responding to the virus. 


Like many other traits or issues, mental illness can actually run in the family. Not only is someone who has a history in their family of a specific type of disorder more likely to also have that disorder, but it even goes a step further. 

Someone who has family members that suffer from any kind of mental illness has a higher risk of developing a mental health issue in their lifetime, even if it isn’t the same one.

Just because someone grows up in a family with mental health issues doesn’t guarantee that they will develop one as well, though. In fact, there are certain preventative measures that can be done in order to decrease the chances of one developing in a child such as proper nutrition and exercise and a good support system at home.

Is Mental Illness a Genetic Trait?

As we briefly discussed above, there is a connection between genetics and mental illness. In fact, there are certain mental health disorders that are more likely to be passed on genetically than others. The most common ones are:

  • Schizophrenia
  • Autism
  • Bipolar disorder
  • Depression

If a family member has one of those mental health disorders, the likeliness that the child will develop a mental health issue, even if it is not the same one that the parent has, is greater. Additionally, if both parents have a mental health disorder, then the child is at an even greater risk. 

While having parents with mental health issues increases the chances that the child might develop a mental health illness, it’s not a guarantee that it happens. Yes, the child is more susceptible to mental illness. 

However, mental illness itself occurs from not just the interaction of multiple genes, but other factors as well. Things such as stress, abuse, or other repeated traumatic events can all increase the chances that the child might develop a mental health condition.

How Does Mental Illness Affect the Brain?

The brain controls just about everything in our body. It controls memory, learning, the senses, and emotion. It also controls other parts of the body, including muscles, organs, and blood vessels. 

It contains billions of nerve cells that must communicate and work together for the body to function normally. When there are any abnormalities in the brain, it can result in mental illness. Connections between nerve cells along certain pathways or circuits in the brain can lead to problems with how the brain processes information. 

This can result in abnormal mood, thinking, perception, or behavior. Additionally, studies have shown that changes in the size or shape of different parts of the brain may be responsible for causing some mental illnesses.

A Complicated Picture

The relationship between mental illness and what causes it can be very complex. It can be very difficult to precisely determine the exact underlying factors that cause any form of mental illness. Different people with the same diagnosis may have totally different risk factors and complications. 

While there isn’t a singular cause of mental illness, various factors contribute to its development. Being aware of these risk factors can help you assess the likelihood that you may develop a mental health issue. This can help you spot any issue early so you can get prompt treatment.

Do You Suffer From Mental Illness?

If you, or someone you know, suffer from a mental health issue, it’s important to get the proper help that they need. Too many times, people turn to drugs and alcohol as a way to self-medicate their mental health issues. This can lead to even more significant issues down the line. 

At Footprints to Recovery, we know that understanding and dealing with mental health issues can be a confusing and scary thing to do. That’s why we offer treatment programs for mental health issues as well as co-occurring disorders. Contact us today to learn more.

Questions about treatment options?

Our admissions team is available 24/7 to listen to your story and help you get started with the next steps.

Are you covered for addiction treatment? Find your insurance
Questions About Treatment?
Get Confidential Help 24/7. Reach Out For More Details About: