I suffer from some forms of light sensitivity, I share this in common with my mother. We share a disorder which causes bright lights to damage the eye very easily, fatty tissues build up in these areas and with TONS and TONS of exposure over time visual problems can come up. These problems make me nearly blind in the  morning sun, even in indirect light, it seems brighter to me.

My father also has a condition which causes him to have blindness at dawn and dusk without special sunglasses.

This is why I prefer the dark, my room is painted black and the blind always down, just because I find light hard on my eyes.

All my biological siblings have really pale skin and light eyes, but I'm the only one whose eyes can't stand much light 24/7. I have a pair of glasses and a pair of really dark tinted sunglasses, which I most likely wear more often.

 If it's because of vampirism I can't say. Does seem so, since I never had this much of a problem before Awakening.

I have a theory on why some vampires have a problem with sunlight.  For myself my tend to be sensitive to sunlight even on completely overcast days.  Also being out in the sun usually makes me feel sick, though I normally do not burn.

Anyway, here my theory:  Some things that I have read about vampires is that with some when someone tries to view their aura it like a void or black hole.  Well black holes pull in energy, even light.  Well sunlight/ sun energy can be very strong and harsh.  I think that for some vampires it is too strong and also not very compatible to their energy system.  So the result is that it makes them sensitive to it and for some even makes them sick.

Just my 2 cents.  Let me know what you all think.

The sun usually bothers my eyes when I am low on energy and my skin gets all tingly when in the sunlight. It gives me the sensation that a bunch of needles are poking me lightly. It gets very irritating. So, I hide inside most of the time or in the shade.

I think this is a chicken or egg thing...

Light sensitivity does tend to go hand-in-hand with vampirism.

While there's a lot of myth surrounding this, there does seem to be a lot of fact backing it up as well.  Vampires tend to be light sensitive.  Is it because they're vampires or is it just that light sensitivity is more common in vampires than the general population?

It's hard to say.  The world may never know for sure.

I am very light sensitive.  I'm finding that as I get older it's becoming worse and worse.  I have a 'normal' day time life and so I just sort of live with it.  The biggest obstacle for me right now...is that as my light sensitivity gets worse, my loved one's patience in it gets worse.  I don't like to go to family reunions or BBQs in the dense summer heat because I always get so sick.  I end up having to go inside and lay about feeling drained and nauseas.  I'm seen as rude, standoffish or just plain b.itchy.  It's like I can't make them understand how horrible direct sunlight really makes me feel.  I wear blue blockers as much as I possibly can and I get eyes rolled at me.  "It's not THAT bright out!"  People huff at me...And trying to explain the intense pain and headaches the bright light gives me is just a lost cause I think...

Just another reason to get dragged down into loneliness if we let it get to us though.   

Just a little tid-bit...vitamin D is synthesized through the skin from contact with sunlight.  People who do not get much sun exposure because of light sensitivity can get deficiencies in vitamin D.  Vitamin D is a big proponent to stave off depression.  It's not a bad idea to take vitamin D supplements.  Doctor's recommend 1000 units of vitamin D a day.  I swear by my vitamin D...