Problems with washing face, hair and brushing teeth

It's something I'm very curious about as it's affected (and still affects) several within my family. 

And yes, within autism groups the focus usually seems to be on resolving sensory issues - collaborative problem-solving with the person to see whether there is anything that makes it particularly offputting (shower head too forceful, bathroom products too smelly, lighting very glaring etc) and substituting something more appealing or less unpleasant).  If the problem persists then, as you suggest, the subject generally moves on to depression or anxiety as self neglect can arise from this.  Plus, of course, if you're battling with social anxiety or simply to stay alive, personal hygiene might tend to be pushed down the list of priorities. 

But, like yourself, I suspect there's something else.  I've known famly members have these problems throughout their lives, irrespective of whether they were going through a stressful period or feeling quite happy, plus also irrespective of the range of products, lighting, bath or shower, softness of towels, whatever adjustments were made.  It was as if these issues were marginal and, in some cases, a red herring altogether.  

The impression I got from one close family member was that this just didn't exist for them as an issue.  The issue, from their perspective, was that others kept mentionning it and trying to get them to do something.  But they didn't really see it and actually responded by feeling hurt or unjustly accused of being mucky (even if they were and even if the other person approached it very gently and sensitively!).  

I'm afraid we eventually just accepted it.  This was the person's preference, although I'm sure that neighbours thought it was a matter of neglect, not having a quiet word or not hinting by getting the person toiletries for their birthday.  i could have assured them it was nothing to do with any of those factors.  

I think that, if it's something you're concerned about, it might be a case of talking through that concern, deconstructing it as it were.  What is bringing it up as an issue here and now, have there been any times when it's been easier or harder and what was going on in your life then, what is making you aware of the problems and can any of this be fed back into a plan that might suit you?  You've said it's not sensory and it's not depression, but saying "it's autism" doesn't narrow it down far enough to enable you to address things (assuming you want to).  So I'm wondering which aspects of autism might be bringing to bear.  Plus hoping that zooming in might be helpful.            

It's something I'm very curious about as it's affected (and still affects) several within my family. 

And yes, within autism groups the focus usually seems to be on resolving sensory issues - collaborative problem-solving with the person to see whether there is anything that makes it particularly offputting (shower head too forceful, bathroom products too smelly, lighting very glaring etc) and substituting something more appealing or less unpleasant).  If the problem persists then, as you suggest, the subject generally moves on to depression or anxiety as self neglect can arise from this.  Plus, of course, if you're battling with social anxiety or simply to stay alive, personal hygiene might tend to be pushed down the list of priorities. 

But, like yourself, I suspect there's something else.  I've known famly members have these problems throughout their lives, irrespective of whether they were going through a stressful period or feeling quite happy, plus also irrespective of the range of products, lighting, bath or shower, softness of towels, whatever adjustments were made.  It was as if these issues were marginal and, in some cases, a red herring altogether.  

The impression I got from one close family member was that this just didn't exist for them as an issue.  The issue, from their perspective, was that others kept mentionning it and trying to get them to do something.  But they didn't really see it and actually responded by feeling hurt or unjustly accused of being mucky (even if they were and even if the other person approached it very gently and sensitively!).  

I'm afraid we eventually just accepted it.  This was the person's preference, although I'm sure that neighbours thought it was a matter of neglect, not having a quiet word or not hinting by getting the person toiletries for their birthday.  i could have assured them it was nothing to do with any of those factors.  

I think that, if it's something you're concerned about, it might be a case of talking through that concern, deconstructing it as it were.  What is bringing it up as an issue here and now, have there been any times when it's been easier or harder and what was going on in your life then, what is making you aware of the problems and can any of this be fed back into a plan that might suit you?  You've said it's not sensory and it's not depression, but saying "it's autism" doesn't narrow it down far enough to enable you to address things (assuming you want to).  So I'm wondering which aspects of autism might be bringing to bear.  Plus hoping that zooming in might be helpful.