There was a lot of talk about blue zones during my travels this week. I’m quite sure that you’re familiar with the concept but if not, we’re talking about those pockets of the planet where people supposedly live longer, happier lives. Over dinner in Tokyo, lunch in Hong Kong and drinks in Bangkok, various conversations ended up focusing on where people live longest, alongside armchair theories to expand on what we already know about picking vegetables in Okinawa and dancing in Greece.If you want to fling a clog at the TV, then watch the Netflix series on the topic. I tuned in a few months ago and attempted to follow along as the presenter tried to link people living in high-altitude Sardinia, the urban sprawl east of Los Angeles and Singapore. I struggled to get to the end of the series. I suspect that the production company did too; I feel as though it might have run into financial difficulties, bolting Singapore into the mix part way through. Should you make it that far, you’ll find yourself asking, “Since when did Singapore become a blue zone? And why are the people featured in and around Orchard Road not particularly old compared to the other zones?” I switched off before the credits but I’m still wondering whether Temasek helped fund the whole thing. The series tries to make much of walking up and down hills, being with family, drinking wine and laughing, and having a purpose in life but my read is that blue zones do not occur in cold, dark places or where people happen to be taller than 178cm. Sardinia, remote parts of the Greek archipelago, Okinawa and Costa Rica are not big hunting grounds for NBA scouts. The Netherlands proves my point. The Dutch do okay, despite their country’s lack of sun and hills to climb, but it seems that even all that cycling can’t help them scrape into Europe’s longevity top ten because they’re simply too tall to qualify. Yes, it’s a thin theory but so too is much of the blue-zoning as trotted out in the series.I have long believed that a bit of daily, personal recognition goes a long way in adding a few years onto your life and, no, I’m not talking about likes on a social-media feed or a video call with your auntie. I’m thinking more about proper eye contact and a good morning, ohayo gozaimasu or bonjour when arriving on the train platform for your morning commute or walking to the grocery store on a Saturday morning. I notice this living in Zürich, where young and old are very good at giving you a nod or a gruezi. I’m most impressed when I’m approached by a bunch of teenage boys on the street and, just when you think you’re going to be ignored, everyone does a polite bow of the head and says hello. Does this make you feel better about the world? Absolutely. Does it make you wonder why this doesn’t happen more often elsewhere? Most definitely.Earlier today I put the recognition theory to the test bright and early on the sunny streets of Stockholm. I tried to make eye contact with one passerby, then another and another, and came up with not so much as a grunt. First, they’re not big on eye contact on the streets of Stockholm and a god morgon to your fellow walker, jogger or shuffling pedestrian is not a thing. Add a layer of data to this and you will note that the Swiss have an average life expectancy that is a good half year longer than the Swedes. So here you have it dear reader: when you finish reading today’s Weekend Edition and venture out of the house, take the time to say a warm hello to those who you pass on the street, smile at the policeman, tilt your cap at the kid on the bicycle and stride along confidently in the knowledge that everyone might live a little longer thanks to your kindness. Monocle might just land its own series on just such a theory.