Feeling tired and weak every day may be due to poor work and rest or pathological factors such as lack of thyroid hormone, depression, etc. can also lead to. 1. Poor work and rest: when a person has long-term smoking, drinking, staying up late and other bad habits, which will feel every day feel so tired and weak phenomenon. 2. Pathological factors (1) lack of thyroxine: thyroxine can increase the excitability of the human nervous system, can make the excitation center in the body in an active state, if the lack of the excitability will be reduced, so that people feel tired every day and the phenomenon of lack of energy. (2) depression: if the patient suffers from depression and other mental illnesses or some underlying diseases, patients are not interested in anything, often accompanied by symptoms such as feeling tired and weak every day. If the phenomenon of feeling tired and weak every day, you should consult a doctor in time to carry out the necessary examination and targeted treatment after diagnosis, so as not to delay the condition.