There are several potential causes of depression that can vary from person to person.
First, there is a genetic component to depression. This means that if a family member has depression or another mental health disorder, then you are more likely to experience depression.
Next, there is an environmental cause of depression—meaning that how you grew up or how you currently live can affect your mental well-being. So, if you grew up with a depressed parent, you may have adopted their behaviors or outlook. Traumatic experiences can also cause depression.
In some cases, medical issues can co-occur with depression. Terminal or chronic illness can significantly alter your mood and cause depression. Alternatively, depression can be a symptom of medical disorders like hypothyroidism or Parkinson’s disease.
Lastly, drug or alcohol abuse can worsen or cause depression in some individuals. Addiction often co-occurs with mental health disorders because people abuse substances to cope with underlying symptoms. However, long-term substance abuse can cause mental health disorders like depression.