Dandruff and dull fur

Hi! 

So my calico cat has quite bad dandruff at the moment as you can see.    I'm quite concerned about it and am unsure whether there's something I should be trying myself at home or whether I should just be making a vet appointment. 

She and her brother eat a good quality dry food (Royal Canin Light Weight Care), she seems to be drinking the normal amount and our apartment is naturally warm so we haven't had to crack the heating on at all yet this winter. I've been giving her little brushes and a lot of fur comes out when I do this, I keep finding little clumps of fur around as well.

Last time we went to the vet (three weeks ago) to get their annual boosters the vet made a comment about her fur being quite dry and listless and the amount that she was shedding but didn't give us any advice. He seemed surprised that she is on a high quality food (they always have been) thought because of the state of her fur. 

Any thoughts much appreciated.  

Change food to whatever high quality canned you can afford and transition away from all kibble. Best advice is higher protein, low phosphorous/magnesium, carb about 3%, limited fish/seafoods. My newly adopted boy came with a dull coat with dander & fur loss, and FLUD diagnosis. I put him on grain free canned, followed advice given by members here, at vet appt. found out we had to go on 'script foods for the FLUD. I got Royal Canin Feline Urinary and in 3.5 weeks, his coat is back to where it was when I adopted him. Another person reports the same thing happened to her cat. Good news is she said once she weaned hers off the RC prescription foods, his coat went back to shiny & healthy in a matter of weeks. Check ingredients of David's Pet Food, low magnesium & phosphorous, Weruva Cats in the kitchen and Natures Variety Instinct, muscle meats of chicken, turkey, rabbit & duck and see what you have available to you that are similar. Good luck getting that coat back to shiny.

ETA I don't think RC products are that bad, not every product is going to work for every cat.

Yes, I agree.  Switch foods to a high quality wet food and her fur and dandruff should get much better.  Even Fancy Feast CLASSICS should show an improvement. 

Or if that is not possible, try adding in some fish oil (salmon, sardine, anchovy, etc.) to their food)