There’s no single cause of depression. It can occur for a variety of reasons and it has many different triggers. For some people, an upsetting or stressful life event, such as bereavement, divorce, illness, redundancy and job or money worries, can be the cause. Different causes can often combine to trigger depression.
Research shows that depression runs in families. Some people inherit genes that play a part in it. But not everyone who has a family member with depression will develop it, too. And many people with no family history still get it. So, genes are one factor, but they aren’t the only reason for depression.
Certain chemicals called neurotransmitters manage mood. When a person has depression, these neurotransmitters might be in low supply or not be effective enough. Someone with the genes for depression may be more likely to have this neurotransmitter problem.
Pregnancy causes emotional and physical demands, hormonal shifts, and stress, all of which may lead to perinatal depression. You may have perinatal depression during pregnancy and after childbirth.
Depression can make caring for yourself and others challenging. Treatment with medication, therapy, or a combination of both can often make you feel better.
Seasonal changes during the fall and winter months, when the days are shorter than in the spring and summer months, may lead to seasonal affective disorder (SAD). A lack of sunlight exposure may alter your circadian rhythm, which regulates hormones and other body functions related to mood.
A healthcare provider may advise light therapy to treat SAD. Some people with SAD notice their depression symptoms typically improve during the spring and summer months.
Serious medical illness lead to depression
The stress and worry of coping with a serious illness can lead to depression, especially if it’s long-term or you’re dealing with chronic pain.
Drug and alcohol use
Drug and alcohol use can lead to depression. Many people with depression also have drug and alcohol problems.
Over 500,000 Australians will experience depression and a substance use disorder at the same time, at some point in their lives.