
Everyone feels sad occasionally, but sadness that affects your daily activities and lasts for more than 2 weeks may be depression.
Depression — a serious mood disorder — is the most common mental health disorder in the United States. It can interfere with your thoughts, your feelings, and daily activities like sleeping, eating, and working. Depression symptoms may be different for different people, though.
Symptoms of depression
If you've been experiencing some of these symptoms most of the time for at least 2 weeks, you may have depression:
- Feelings of anxiety or hopelessness
- Feelings of guilt, emptiness, or worthlessness
- Difficulty sleeping or sleeping too much
- Decreased energy or fatigue
- Restlessness or trouble sitting still
- Lack of interest in activities that used to make you happy
- Moving slowly or difficulty getting going
- Irritability
- Difficulty concentrating, remembering things, or making decisions
- Gaining or losing weight unintentionally
- Aches, pains, headaches, or cramps with no noticeable cause or that don't improve with treatment
- Thoughts of suicide or death, including a plan to commit suicide
If you or someone you know is thinking about suicide, call the National Suicide Prevention Lifeline (Lifeline) at 1-800-273-TALK (8255), or text the Crisis Text Line (text HELLO to 741741).

SLIDESHOW
Learn to Spot Depression: Symptoms, Warning Signs, Medication See SlideshowEffects of depression
Depression can affect your behavior and your life in many ways. Its effects on behavior will be different depending on age and individual circumstances. Some behavioral symptoms of depression are dependent on age.
In children
Depression symptoms in young children may include:
- Anxiousness
- Crankiness
- Pretending to be sick
- Refusal to go to school
- Physical attachment to a parent
- Worrying that a parent may die
In older children and teens
Older children and teens often have other disorders that occur along with depression, like ADHD, eating disorders, or substance abuse disorders. They may also:
- Sleep excessively
- Have increased appetite
- Get in trouble at school
- Sulk
- Have low self-esteem
- Become easily frustrated
- Engage in risky behavior
Young adults
Young adults may also have co-occurring disorders like generalized anxiety, social phobia, panic disorder, and substance abuse disorders. They're more likely to:
- Be irritable
- Gain weight
- Sleep a lot
- Have a negative view of the future
Middle-aged adults
Middle-aged adults with depression frequently report:
- Gastrointestinal symptoms like diarrhea or constipation
- Decreased libido
- Depressive episodes
- Early waking
- Insomnia in the middle of the night
Older adults
Older adults frequently have other medical conditions that contribute to depression. They may also have:
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Causes of depression
Researchers don't know exactly what causes depression, but it may be related to several different factors including the following.
Life events
Long-term stress caused by work, an abusive relationship, unemployment, or loneliness is more likely to cause depression than short-term stress. However, short-term stress may also act as a trigger if other factors are also present.
Family history
You may have an increased risk of depression if you have family members with depression.
Drug and alcohol use
Depression and risky behavior often go together. Many people who have depression also have substance abuse disorders. Abusing alcohol or drugs may cause depression, or it may be caused by it.
Serious illnesses
The stress of coping with a serious illness, especially if it involves chronic pain, can lead to depression.
Changes in your brain
Depression isn't just a result of a brain-chemistry imbalance. Other factors like those listed above can change the way your brain regulates your mood as well.

QUESTION
Depression is a(n) __________ . See AnswerTreatment for depression
The good news is that depressive disorder frequently responds well to treatment. Your doctor will work with you to develop an effective treatment plan that may include any of the following:
- Psychotherapy like cognitive behavior therapy, individual therapy, or family therapy
- Medications like antidepressants, antipsychotics, or mood stabilizers
- Light therapy — which uses a lightbox to provide full-spectrum light that can help regulate the hormone melatonin
- Acupuncture
Brain stimulation therapies may be used if other approaches don't work.
Lifestyle modifications
Besides working with your doctor or therapist to develop a treatment plan, you can make helpful changes to aspects of your lifestyle, and they include the following.
Several studies have found a relationship between eating a poor-quality diet and symptoms of depressive and anxiety disorders. A whole-food diet, on the other hand, supplies a variety of plant compounds, nutrients, vitamins, and fatty acids that may offer protection.
People who exercise have fewer depressive symptoms. Regular exercise during childhood is also associated with a decreased risk of developing a depressive disorder as an adult.
Relaxation and meditation
Although more studies need to be done, relaxation and meditation practices like mindfulness may help improve your mood. Meditation can change your brain in ways that reduce anxiety.
Adequate sleep
Getting enough sleep is important for your health and well-being, and problems sleeping are often associated with depression. Depression can also cause insomnia. Increasing your physical activity and limiting caffeine may help you sleep better.
Socialization
Positive and supportive relationships have a beneficial effect on your physical and psychological health. Making an effort to stay connected with your family and friends can help improve the symptoms of depression.
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