No. All of the responses by Toady have left us to believe sex, drugs, bowel movements, and urine shall be left outside of the realm of the simulation.
Well, sex requires two units to make contact with each other now, but that doesn't really count as a simulation, though you can essentially castrate something with attacks if you feel so inclined with how body parts are treated now.
Drugs technically exist already, in the sense of as mentioned before:
I doubt it will ever be simulated in Dwarf Fortress though, despite alcoholism being simulated in a scarily realistic fashion. Including domestic violence and black out rages. Like seriously...
And teeeeeeeechnically you could consider vomitting a "movement of the bowels", just the other way, and units tend to do this constantly.
Now i'm not saying stuff is going to be implemented to the fullest extent that some niches are demanding it, more just that a lot of the stuff already
is kinda in the game, to a limited extent.
I would actually kind of find it quite interesting if dwarves would sometimes smoke tobacco or something like that as their habit, rather than only require drink to avoid having their functioning slow down, if just because of the interesting effect on gameplay it may have, such as different dwarves or cultures which may despise or otherwise dislike particular habits, whether it's the act of smoking or drinking or the act of being in the presence of others who do so habitually, especially with the new effects smoking would offer (more directly increase the focus of the worker, induce long term deterioration of lungs or "anemia" (which would be easier to track rather than adding cancer as a separate mechanic, I think at least), making clouds of smoke in enclosed areas which can cause varying reactions to those present, etc.
I actually don't like smoking much IRL, but I feel like, mechanically and simulatively, it may have it's place in DF in one manner or another.
That all said, the era DF takes place in might not be as friendly to the expectations of certain activities, though we can afford to be a little flexible what with potentially randomly generated flora that was mentioned to be added in the future, as well as just dwarven/goblin/elven/humans-exploiting-the-other ingenuity.