It's embarrassing. More likely caused by all of the bright lights
just illuminating the problem.

Bright lights, like a bright flashlight might be useful when
examining your cat.

Brushing definitely helped my Kitty lose some dandruff.

If you are noticing it more lately, maybe shedding has something
to do with it. Summer is coming.

Others have more experienced opinions.

Good luck.

...

I have that trouble with my girls. Oddly Pearl's disappears now and then. I
canNOT figure out the difference from when she has it (looks all unkempt and
like an unowned stray) to when she does not! I have *heard* adding fish oil
to the diet may help. I too do a wet paper towel sometimes. It's just that
black cats show up the dander SO much more. Makes it hard to tell if they
have a lot or it's just more noticable. But Sugar used to have pretty bad
dandruff and for several months now her hair has been really good. It's
frustrating.

Also, black cats just show flakes more. Contrast and all.

I assume the vet checked for real skin problems that could cause it (mites,
allergies, and so forth). So, I'll assume it's the usual -- dry skin.
Since he won't eat wet food, he needs more oils and water in his diet. Many
cats don't hydrate well with just dry cat food, so try adding a little water
to the dry (makes it softer, but not soggy) and add a little (olive or other
light vegetable) oil to either his food or water. Some cats won't drink water
with oil in it, so if he doesn't like it, put it in the food. Like a teaspoon
every 3 days or so.
You can also try skin conditioner for pets. Make sure it is for cats so it is
safe for him when he cleans himself. They sell skin conditioners at the pet
store. They even have pills you can give them with the oils in it if he
refuses more natural oils in his food and water.
Daily brushing with a slicker brush will help flake off the dry skin cells.
In the beginning, it will look even worse because it's flaking. After a
couple weeks of added water and oils and brushing, it should look a lot
better.

Other things you can try:
* a little butter daily (be careful for lactose intolerant cats! start with
just a tiny bit)
* Vaseline / petroleum jelly
* Semi-moist cat treats
* Oatmeal bath (soothes skin - make sure you get PET oatmeal bath so it's
safe)
* 15-30 minute humidifier treatments or put in bathroom, close door, and run
a hot shower so it gets all steamy in the room.

Now, if his dry skin is actually caused by something else than a lack of oils
and water, such as food allergies or an allergy to something in the
environment, some of these may be completely ineffective. If he has
allergies, you'd need to be real careful about anything you put on him or
that he ingests. So, if you suspect allergies, go slow and only try one thing
at a time in case he has a reaction.

HTH

My black cat's dandruff was much worse before I began treating her
for an overactive thyroid. Maybe get his checked.

My vet says it's usually an Omega 3 deficiency in cats. You can add fish
oil (I have purchased capsules and squirted it onto their food,) or buy
food that has more Omega 3 than Max Cat.

Good luck,

Rhonda