The difference between men and women with respect to their age preferences, when it comes to sexual partners, is smaller than earlier believed. A recent study shows that also men become interested in older and older women as they themselves age.

While earlier research has indicated that even older men prefer young women, a recent study by Jan Antfolk at Åbo Akademi University suggests that this is only partly true. It is true that men, more than women, tend to maintain a sexual interest in younger partners. Contrary to what has been reported from earlier studies, most men and women are also sexually interested in partners their own age throughout life. Most sexual activity occurs between partners of approximately the same age. 
Homosexual and bisexual men and women differ very little from their heterosexual counterparts. The only exception from this is that homosexual men are somewhat more likely than bisexual and heterosexual men to have sex with partners younger than themselves.
The study was conducted in Finland and included 878 adult men and 1789 adult women. The study was recently published in Evolutionary Psychology.

http://journals.sagepub.com/doi/abs/10.1177/1474704917690401

Full bibliographic information
Age Limits
Men’s and Women’s Youngest and Oldest Considered and Actual Sex Partners
Jan Antfolk
First Published January 25, 2017
The study was published in Evolutionary Psychology.
Link to the on-line publication: http://journals.sagepub.com/doi/abs/10.1177/1474704917690401