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Heather Honore Goltz, University of Houston-Downtown and Matthew Lee Smith, Texas A&M University

(THE CONVERSATION) Humans are sexual beings. This urge does not stop when the clock strikes 60. Or even 90.

Young adults may deny older relatives are having sex, but sexual activity is a strong indicator of healthy aging and vitality. In fact, sexual activity is roughly equal to climbing two flights of stairs.

Sex education and research use a medical model of sexual health focusing main...