That all changed the day I learned meditation. I have been practicing for 10 years now and haven’t been sick in the last eight of those.
I personally believe nature didn’t intend for us to feel sick, tired, and stressed; in fact, our bodies are equipped with a powerful internal pharmacy designed to keep us from getting sick. However, stress can overwhelm our bodies and prevent immune function from running optimally. When the body is stressed, it is basically preparing for a predatory attack, so there isn’t much energy left to run maintenance functions.