Immune system is the system which protects your body from toxins, bacteria, viruses and other dangerous pathogens. There are many factors which can cause weak immune system which include blood transfusion, inadequate sleep, ultraviolet radiations, exposure to chemicals, drug therapies, athletic over training, surgery and certain bacterial and viral infection. Some of the common signs of weak immune system are constant fatigue, lethargy, recurring infections, depression, frequent diarrhea, tiredness, stress, insomnia and dark circles around eyes. Weak immunity can cause all types of illness in a person.

see all - http://www.flexablog.com.ng/2016/08/home-remedies-for-boosting-your-immune-system.html