My daughter has been primal from day one. Dairy she has is kefir made from raw milk, raw cheese and grass fed butter, greek yoghurt and otherwise just fruit, veg and meats with lots of fat, animal fat and coconut oil. Very occasionally some soaked macadamia nuts.
I have just noticed white spots on her fingernails, I have heard this is a zinc deficiency.
White spots on fingernails are generally a sign of mineral deficiency. Does she consume bone broth regularly? What is her digestion like? Is she supplementing D and K (or anything else)? I would up her bone broth, support digestion with fermented foods and even HCL if needed, plus D, K, Zinc and magnesium.
I've read in sports magazines that bumping or pinching your fingertip/nail results in those white spots. I've noticed that's happened to me a few times, usually with doing heavy yard work and remodeling around our house. Maybe she's biting or pinching them?
I've had this since childhood, though I am not sure what causes it. After several months of paleo/balanced eating, it does seem to be going away. I would be interested to know if it is caused by a deficiency.