Most people feel low from time to time due to work pressures, relationship or financial problems and other common issues. But at what point do the blues move into the more serious category of clinical depression?

Sadness, feelings of depression and the illness of depression are all very different states of mind.

According to the National Institute of Mental Health (NIMH), you may have clinical depression if you’ve had several of the following symptoms all day, nearly every day, for at least two weeks:

• Persistent sad, anxious or “empty” mood.
• Feelings of hopelessness or pessimism.
• Irritability.
• Feelings of guilt, worthlessness or helplessness.
• Loss of interest or pleasure in hobbies and activities.
• Fatigue or decreased energy.
• Moving or talking more slowly.
• Feeling restless or having trouble sitting still.
• Difficulty concentrating, remembering or making decisions.
• Difficulty sleeping, early-morning awakening or oversleeping.
• Appetite or weight changes.
• Thoughts of death or suicide, or suicide attempts.
• Aches or pains, headaches, cramps or digestive problems without a clear physical cause or that do not ease even with treatment.

Often, people with clinical depression also experience excessive crying, social isolation and loneliness. They may describe depression as a constant dark cloud looming over their lives.

During the fall and winter months some people also face a type of depression called Seasonal Affective Disorder (SAD). It tends to occur with seasonal changes, particularly when the days get shorter. Most people with SAD feel better by springtime, when the days get longer and there’s more sunlight.

Depression is common among adults. According to the NIMH, about 15.7 million adults in the United States, or 6.7 percent of all adults, had at least one major depressive episode in 2014. Experiencing just one episode of depression increases your risk for another episode by 50 percent.

Don’t suffer in silence. Depression is a medical condition that can be treated. If you have several depression symptoms, it’s time to seek help. There are many good options for treatment these days. Make an appointment with your doctor to talk about your symptoms and treatment options.