The Elder Pliny died at 56 - but at Pompeii, and was physically very good at the time, his nephew Pliny the Younger aged 62, Tacitus at 61, Cicero 63, Livy 76: five at random, but it wasn't as bad as you make out. Nor were they really a fresh fruit and veg lot if you read accounts of their feasts! Alexander the Great dies at 33, true, but of poisoning - food, possibly,
I think hygiene had a lot to do with it. Transmission of infection, particularly at the baths, would have been common. Semmelweis' epiphany of the spread of disease by dirty hands was a long way away. Another scourge was tooth infections, there is evidence form several mummies that death from tooth abscesses was the most likely cause. Water quality would be another factor. But if you think it was a stress free life, think again! You didn't get to be a wealthy Greek or Roman without treading on some peoples' toes. Reading the letters of Pliny it's clear that they had exactly the same problems that we do nowadays (excluding the vaccine issue
) - boundary disputes, land taxes, trade problems, slave (employee) issues - and if you were heavily into politics then a knife was always a likely way to die. Alexander the Great died at 32, for example, probably from poisoning - food or water, possibly; hygiene - or deliberate.
