” Clinical depression goes beyond a feeling of sadness or “feeling down.” It is a serious mental health issue that requires treatment. Depression is unlikely to improve on its own.  Sadness is a natural human emotion. It can occur as a response to loss. It can be the result of experiencing something unpleasant or uncomfortable. Sadness or “feeling down” usually lessens on its own over time. It is often not a constant feeling. Sadness may come and go. It is usually triggered by a particular experience or event. Clinical depression is more than sadness. It is not a feeling that people can just “get over.” It rarely lessens over time. It is usually near-constant or constantly present. It may not be triggered by any particular event or experience. It can be so overwhelming that it interferes with daily living. Clinical depression may manifest differently in different individuals. You may not have all of the symptoms of this disorder. Symptoms usually interfere with your daily life activities and may cause significant distress or dysfunction. If you frequently experience five or more of these symptoms, you may have clinical depression:  Changes in sleep habits Changes in eating habits Inability to focus or concentrate, “feeling fuzzy” Fatigue or lack of energy Loss of interest in things you used to enjoy Irritability or restlessness Weight loss or weight gain Feelings of despair, hopelessness, or worthlessness Physical aches, pains, headaches, cramps, and other physical symptoms that have no clear cause Depression has many causes, and researchers are not yet entirely certain how it works. Early trauma may cause changes in how your brain handles fear and stress. Many studies suggest that clinical depression may be partly genetic. Life changes such as losing a loved one or going through a divorce may trigger an episode of major depression.  Clinical depression is a complex disorder. It may be partially caused by trouble with neurotransmitters in your brain, such as serotonin and dopamine. Medication may help...

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Write a summary of the previous text in Vietnamese:
So sánh giữa bệnh trầm cảm và “u sầu”. Nhận biết những triệu chứng của bệnh trầm cảm. Biết nguyên nhân gây nên trầm cảm. Nói chuyện với bác sĩ. Tìm sự giúp đỡ của chuyên gia sức khỏe tâm thần. Liên lạc với nhà cung cấp bảo hiểm. Giữ liên lạc với gia đình và bạn bè. Ăn đúng cách. Ngủ tốt. Tập thể dục.