facebook If you haven’t already had to grapple with whether or not you should friend your Mom, you may well be facing that conundrum soon.

Women over 55 are the fastest-growing demographic on the social network,  their ranks swelling a jaw-dropping 175.3 percent since late September, according to InsideFacebook.

Overall, users over 26 comprise the fastest-growing segment on the social network — originally geared at college students, remember? Forty-five percent of Facebook’s 45.3 million active US users are 26 years old or older.

Teens, meanwhile, comprise less than 12 percent of registered users.

While registration rates continue to rise in all demographics, there are almost double the number of 55+ women on Facebook than their male counterparts.

This should have interesting implications for marketing and advertising on Facebook in particular, and social media in general, going forward. Socially, women tend to be viewed more as “connectors” than do men, a truism or stereotype (take your pick) that seems to be reflected in these numbers.

Traditionally, of course, women control the overwhelming majority of the billions in household-related spending. It’s going to be interested to watch which advertisers jump on Facebook to take advantage of reaching the older women jumped on campaigns such as Dove’s Real Beauty and spread them virally.