I've known quite a few asexual types, and many of them (not all) seemed to have issues of some sort with their sense of smell. One case was from an experimental nasal stimulant that permanently fucked up his ability to smell things, but the others seemed to simply have sinus issues in general. Pheromones are believed to be a strong influencer of behaviors, both when it comes to competition and attraction, and as such I'm left wondering how someone with a damaged sense of smell might respond differently towards social cues both current and acquired while growing up. Also, would they be immune to weaponized forms such as Gay Bombs?
Seeing as there's quite a few self-proclaimed asexuals here, I figure that posing the question here might lead to something interesting. I personally have a strong sense of smell, and I've found myself able to notice when that's influencing my behaviors through watching my own responses towards different sources in a somewhat disconnected-from-myself sort of way, but the opposite being the case for other people has had me on-and-off interested in the possible connection just as much as other seemingly strange ones (like schizophrenics having sensory vulnerability risks with many I've met showing a common problem with light).
I figure it could be a coincidence, but I don't really know.
My sense of smell is fairly refined and sensitive enough. Smells do seem to hold some greater perceptual importance on the hierarchy, for a smell can change the context of a situation rather suddenly and noticeably. I do wear glasses, so my eyes are generally poorer in the eyesight department, though. Sound is the one sense with which I place greatest importance on.
Thing is, the sexual urge feels similar to hunger to my mind, in some way. Is it because of this prominence of smell? Is it some strange form of synesthesia?
And, tbh, these sensory sensitivities and anomalies seem somewhere on a par with the autism spectrum. Whereas autism seems to make the filteration of sensory input unmanageable to some extent, could this be easy to misdiagnose with someone that has these other sensory deviations?
Looks like this question's been asked elsewhere a few times.
Just a theory...SENSE OF SMELL has a (questionable) poll that claims 37.38% of the asexuals who voted within the topic have an issue with their sense of smell (77 vs 129).
There's also a reddit topic on it: Lack of smell & asexuality, and a series of search results debating/wondering this potential coincidence.
It still has me wonder if there may be partial levels of ansomnia that could otherwise be easily ignored from there being more obvious forms of scent still working, or if perhaps it's still perceived but is otherwise not processed to mean anything, like some sort of a pheromone blindness.
Buttered Toast stated: source post
I do wear glasses, so my eyes are generally poorer in the eyesight department, though.
How much would you say that you read faces and body language?
Primal stated: source post
Have you started on the niacinamide...?
Not yet, I've looked into it a bit more, but otherwise have been bad about grocery store trips this week. 
I'll let you know when that changes, as it's still an interesting idea.
Very interesting. I would not consider myself asexual, but rather disinterested or unmotivated toward sex to a degree I almost never see in others.
When I worked at Walmart, one of the sections I stocked was the fragrance section of the chemical aisle. There were probably 60 different scents, and people would feel ill trying to stock that particular part of the aisle, because all the combined scents were overwhelming to them. I smelt nothing when performing the same job. I would actually have to take a bottle and put it close to my nose, or spray something right in front of me to smell anything I was stocking.