It is the emotion that arises in the face of threat to survival. It can be a sudden fright or a chronic state of stress and anxiety, for example experiencing a workplace harassment situation for months.

Fear depletes Kidney-Qi and causes Qi to descend to the lower burner producing, for example, enuresis or diarrhea after a fright, weakness in the knees. The Kidney stores the energy that gives us adaptability to stress and changes. When Kidney is weak, changes or stressful situations become more threatening to us. Long-term it can deplete Kidney-Yin and give symptoms of empty-heat in the Heart: insomnia, night sweats, tachycardia... The person can also be fearful if they have Gallbladder-Qi deficiency or Liver-Blood deficiency.

If the fear is very intense it can consume Kidney-Yang and appear greying, incontinence.

Different behaviors arise to face fear. For example the inability to face it, passive attitude, it paralalyzes and avoids the situation. Or faces the situation but with fear does it with much tension and gets exhausted, consumes much Kidney-Yin and Liver-Blood. When it has gone through the situation it has become "burned out", it costs them to recover. It can enter a depression.