NP here. I get lab work done yearly to make sure I don't have any deficiencies. Everything checks out great, but my nails are also very, very brittle.

How is your diet? That's probably the most important thing--make sure you have enough protein, calcium, and fat in your diet.

Also, you can protect your nails by wearing gloves when washing dishes, etc.

Nail polishes and chemicals just mask the problem.

Also, make sure you don't have a fungal problem.

anyone have advice for brittle nails that break/split constantly? I tried to buy nail polish hardener, but those don't help. is there a type of vitamin that helps with this? thanks.