What Causes Mental Illness?

The National Alliance on Mental Illness (NAMI) defines mental illness as a medical condition that disrupts a person’s thinking, feeling, mood and ability to relate to others, and as being associated with distress or impaired functioning. The most common forms of mental illness are anxiety disorders, depression, bipolar and other mood disorders, eating disorders and schizophrenia.

It is important to understand that there is no one underlying cause for mental illness; it is caused by a combination of biological, psychological and environmental factors. What we do know is that it is not a character flaw orcaused by personal weakness.

BIOLOGICAL: Susceptibility to mental illness can be passed on in families through genes, but this does not mean that a person who has a mother with bipolar disorder or an uncle with depression will experience the same fate. Mental illness occurs from complex interactions of multiple genes and other factors—such as stress, abuse or a traumatic event—which can influence, or trigger, illness in a person who has an inherited susceptibility to it. Some mental illnesses have been linked to a chemical imbalance of neurotransmitters, to infections, poor nutrition and exposure to toxins, such as lead.

PSYCHOLOGICAL: Some of the factors that might contribute to development of a mental illness include severe psychological trauma as a child such as emotional, physical or sexual abuse; the loss of a parent; or neglect.

ENVIRONMENTAL: Certain factors such as death of a loved one, divorce, a dysfunctional family life, a stressful job or substance use by a person’s parents can trigger symptoms in a person who is susceptible to mental illness. This might also include social or cultural expectations; for example, a society that associates beauty with thinness can be a factor in the development of eating disorders. No matter what the cause, mental illness is not something one can just “snap out of.” There are many treatments for mental illness, including but not limited to medications and therapy. Good nutrition, regular exercise, adequate sleep, supportive friends and meaningful paid or volunteer activities contribute to overall health and wellness as well.