How long can someone really live, if they are given optimal conditions–advanced medicine, including full vaccination offerings, access to antibiotics for bacterial-based infections, immediate care and resolution of cuts, etc.–and they live in a relatively pollution-free area, have good genes, don’t smoke, eat reasonably well, including not eating a lot of processed foods injected with chemicals and hormones?
We have no idea, though many of us in the Western world continue to believe that 120 years is the longest someone can live, based on the fact that we’ve never observed and documented anyone living in such an environment into their 100s. A vaccination for polio came in the 40s, smallpox was eradicated in the 60s. Then, that generation and the next, in the western world, began getting fed a lot of mass-processed foods including industrial feed lot/slaughterhouse beef, and all of the additives and preservatives and pesticides that were found to be cancerous in the processing of food. With the introduction of GMOs and hormones in our food, we are still at the early stages of seeing how many of us might get some kind of cancer from these artificial additives to the food production process.
We may never know if someone can live much beyond 120 years. The first generation who has fully benefited from all of the modern vaccines, the baby boomers, have also experienced a planet full of pollution and food full of carcinogens. That generation and the ones that follow it may survive all of the diseases, famines and wars that killed previous generations, only to die from so many diseases caused by humans. The best we can hope for is a handful of wealthy people or perhaps poor people who got all of their shots and lived mostly out of the way of industrial pollution and ate mostly healthy foods (of course, pollution and GMOs completely cover the earth so it’s not possible for anyone to completly avoid them) dodging all of the contemporary bullets being thrown at everyone, survive the worst of climate change, and reach an age of the upper 100s, before the earth is completely destroyed by careless humanity.