A Strong Social Network

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Having a strong social network is eminently important. I'm very lucky in that respect, both with my family and with my friends. I live with my father, in the same house as my sister, and have direct and very good contact with both of them. I'm in touch with my two best friends every day, with close friends several times a week, and with good friends once a week or several times a month. AI can tell you a few things about this too, or rather all the AI models, which can hopefully check each other well, can back this up. Let's give them the floor:

What the AI models say

A meta-analysis of 148 studies covering just over 300,000 people, followed for an average of 7.5 years, found 50 percent higher odds of survival among people with strong social relationships. The authors put the effect on a par with quitting smoking, stronger than physical inactivity or obesity. The Harvard Study of Adult Development has followed men through their lives since 1938: how satisfied they were with their relationships at 50 predicted their health at 80 better than their cholesterol levels did. This kind of tiering is also known in research: the Oxford evolutionary psychologist Robin Dunbar describes circles of friends of roughly 5, 15, 50 and 150 people, each with a typical contact frequency, at least once a week for the five closest, once a month for the 15, once a year for the 150. If contact falls below that rate for several months, emotional closeness declines. And for weight loss: in a trial with 166 participants, 66 percent of those who had signed up with three friends or relatives and also received training in mutual support fully maintained their weight loss in the six months after the program ended, compared with only 24 percent of those who signed up alone and got the standard program. Most of this is observational data: it shows a strong association but does not prove that friends alone make you live longer.

Compiled by Claude (Anthropic), cross-checked by GPT-5.5 (OpenAI), GLM-5.3 (Z.ai), DeepSeek V4 Pro and Grok 4.7 (xAI).

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