I have just read the details of a new study based at Anglia Ruskin university which found that marriage or having ever been married seems to prevent cancer. It is obviously not the act of getting married but for some unknown reason people who have been married or who are married are much less likely to develop cancer. Again, surprisingly, women benefit more than men. Researchers don't know why although they hypothesise a few ideas.
Worth a look though.
https://theconversation.com/does-marriage-prevent-cancer-and-who-benefits-the-most-280297
It has since been picked up by lots of news agencies