Isolation and loneliness can be terrible for your health in many ways and being social is very important in preventing dementia. Those who are socially active had 70% less cognitive decline than those who are socially isolated, thus less socially active. On the other hand, extreme isolation can increase your risk of dementia by 40%!
There are several important levels of relationships: confidants, good friends, and acquaintances (including “consequential strangers”). These social contacts should include 1-2 confidants (people you can call in the middle of the night for help), 3-7 good friends (people you enjoy spending time with on a regular basis) and having at least 7 acquaintances (people in your community seen regularly who know you and your talk to; examples include your neighbor, fellow dog walkers, barista, hairdresser/barber, or library worker). Volunteering in activities that help others appears to be especially beneficial.