Especially if they don't have pets.
The research was published in the Proceedings of the National Academy of Sciences.
Scientists studied 40 men with no health issues aged between 20 and 40.
20 had grown up in a metropolis with no pets while the other half had grown up on a farm.
They were asked to give a speech in front of a group of observers and asked to solve a problem within a specific amount of time.
Blood and saliva samples were taken before the test and after five, 15, 60, 90 and 120 minutes after.
They were tested for inflammatory immune response.
The results showed that the men who grew up in urban environments had an exaggerated inflammatory immune response.
This is because they were not exposed to microbes while growing up, therefore the immune system does not develop a balance between inflammatory and noninflammatory agents.
It can lead to higher immune reactivity that makes them vulnerable to allergy and autoimmune diseases.
If being brought up in an urban environment, to compensate for the hyper immune system, children should have:
This will expose the kids to microbes that will help boost their immunity.