A 2009 Pew research survey administered to 2,969 adults between the ages of 18 and 80 years found sizable differences between informal markers of old age. To the question: “WHEN DO YOU CONSIDER A PERSON OLD?” The percent breakdown for categories of informal markers (e.g., chronological age, memory lapses) by the % of people who endorsed each category was as follows:
79% of persons endorsed “turning 80 years old” as a sign of “being old”. Lack of sexual activity was endorsed by only 33% of respondents as a sign of being old. To conclude: Lack of sexuality was only a minor informal marker endorsed by this group of respondents that a person is old. For these people other things; years of age, independent function, memory loss are more prominent informal markers that a person is old.
Pew Research Center (2012), Washington, DC 20036 p 202.419.4300


Women marrying a partner seven to nine years younger increase their relative mortality risk by 20% compared with couples where both are the same age. But the relative mortality risk of a husband who is seven to nine years older is reduced by 11%.

