Changes

Every time someone moves to a new country all the variables (climate, law, food, microbiome etc.) that affect health, productivity and happiness change. Travel can be harmful and tracking could both detect and illustrate a disease. Moving between countries could make a great QS experiment because its guaranteed to produce some interesting changes. Those could be very beneficial as in some rare cases they have been for me.  

Every time someone moves to a new country all the variables (climate, law, food, microbiome etc.) that affect health, productivity and happiness change. Travel can be harmful and tracking could both detect and illustrate a disease. There is probably no group more likely to catch a new interesting disease than travelers. Moving between countries could make a great QS experiment because its guaranteed to produce some interesting changes. Those could be very beneficial as in some rare cases they have been for me.