The More Friends You Have, the Longer You're Likely to Live

 進化心理学者が解き明かす「人間の友情」

運動不足より、友達不足のほうが危険─「友達の数」があなたの寿命と健康に与える“深刻な影響”

The More Friends You Have, the Longer You're Likely to Live

友人と交流して健康促進したいと思うが、

Dunbar defines the concept as based on the frequency with which one expends an effort to make contact with a particular person. The “seam line,” as he calls it, is one year: “In other words, if a year has passed and you didn’t bother to make contact with a particular individual, you are probably not truly friends.”

仕事以外で、一年いっぺん連絡をとる人たちってそんな多いのか？