Keratin... it's a natural substance that makes the nail harden.
dirt
smoking
Calcium
No, Sikhism does promote hygeine and long fingernails would be really hard to take care of.
theres probably a cheese mole in there somewhere. dig him out! or, your smelly fingernails just need a good scrub! not that hard!
The deep *vertical* lines in your fingernails are genetic. If you have *horizontal* ridges in your nails, you should see a doctor.
picking warts on your bum and casual worms.
You can buy nail hardeners in stores and just apply and they will be hard
Fingernails are normal in the human body. Please be more specific in your question.
there is a fluid in your blood that make hormones fizz and makes a hard nail coming from your nails!
The white area in fingernails and hair are caused by air. That's why snow is white and not blue. Little bumps and bruises that are done to the bed of the nail cause these imperfections.
I dont think so. I have never heard of anything like that before. I do know that when you are pregnant and taking pre-natal vitamins your hair is shinier and your fingernails are stronger.