A: Thank you for this great question from a follower.
The immune system gets stronger by learning to differentiate between friendly microbes and unfriendly microbes. Friendly microbes are present in our daily environment in the dirt and in our homes. Bad microbes include viruses such as the common cold that can make us very sick. Exposure to friendly microbes in our everyday environment help train the immune system for when a true threat from a bacteria or virus presents itself. Exposure to multiple unfriendly microbes just makes us sick with no evidence of strengthening the immune system. Play in the dirt. Embrace the three second rule. Avoid unnecessary exposure to viruses.