The stronger your immune system, the better you are at fighting off viruses and infections. Vitamin D, a.k.a the sunshine vitamin, plays a vital role in boosting your immune system.  There are a variety of lifestyle factors that can negatively impact your immune system. Such as;  A poor diet (regularly consuming processed foods) Smoking (worsens circulation and oxygen levels) Excessive alcohol consumption (alcohol weakens the immune system by impairing immune cells...