“It increases our levels of oxytocin, which is our bonding hormone, so it strengthens our emotional attachments. It also gives us a spike in our serotonin levels, that natural feel-good chemical which helps regulate our mood in a positive way, making us feel less stressed, happier and more emotionally stable,” she says.
Article source: https://www.huffingtonpost.co.uk/entry/a-12-minute-phone-call-a-day-can-keep-the-doctor-away-heres-how_uk_64109c55e4b0a3902d2d13ec