Many people periodically have bad days when they just seem to be in a bad mood. When a bad mood isn’t short-lived, this might be a potential indicator of depression.

Depression is a common mental disorder that, according to the World Health Organization, affects more than 300 million people across the globe.

The WHO notes that despite the fact that there are known and highly effective treatments for depression, fewer than half of those suffering from depression receive such treatments. Furthermore, in many countries, fewer than 10 percent of people with depression receive treatment.

Learning about depression and how to recognize its symptoms may compel people battling it to seek treatment for this very common and treatable disorder.

Why do I have depression?

Everyone has a bad day here or there, but people with depression may wonder why theirs are more than just a bad day. The WHO notes that depression is a byproduct of a complex interaction of social, psychological and biological factors. Exposure to adverse life events, such as unemployment, the death of a loved one or psychological trauma, can increase peoples’ risk of developing depression.

Depression also may be caused by physical conditions. The WHO says cardiovascular disease can lead to depression.

What are the symptoms of depression?

The Mayo Clinic notes that one in 10 people whose depression goes untreated commit suicide.

That only highlights the importance of recognizing the symptoms of depression and acting once any have been identified or suspected. Symptoms can include:

Difficulty concentrating, remembering details and making decisions

Fatigue

Feelings of guilt, worthlessness and helplessness

Pessimism and hopelessness

Insomnia, early-morning wakefulness or sleeping too much

Irritability

Restlessness

Loss of interest in things once deemed pleasurable, including sex

Overeating or appetite loss

Aches, pains, headaches, or cramps that won’t go away

Digestive problems that don’t get better, even with treatment

Persistent sad, anxious or “empty” feelings

Suicidal thoughts or attempts

Anyone who has exhibited any of the aforementioned symptoms or even those who haven’t but suspect they might be suffering from depression should visit a physician immediately.

The WHO notes there are a variety of treatments available to people who have been diagnosed with depression, and doctors will determine which might be the best for each patient.

To make that determination, doctors may inquire about the duration and severity of symptoms as well as family history and whether or not the patient has a history of drug or alcohol abuse.

Depression is a common mental disorder that too often goes undiagnosed. Seeking help the moment symptoms are detected or suspected can help people overcome the disorder.