In my other life I was a nail technician... so I can speak from personal experience! Any kind of artificial nail enhancements, be it gel, acrylic, bio, etc., ultimately damage the nail. They look fab on but once you take them off, your own nails take a LONG TIME to get back to normal, IF they ever do! These enhancements are toxic chemicals which damage the cell structure of the nail bed. Regular manicures may keep your nails trim and neat but they will never correct the possible underlying health issues. After all, if a wall in your house has damp, you don't just paper and paint over it!
Splitting nails, as another answer suggested, are an indication of internal body imbalance, be it lack of water (dehydration) or lack of essential vitamins and/or minerals and fatty acids, such as fish/plant oils. You need to take a long hard look at your dietary habits, especially how much water you drink and how many fresh vegetables and good oils you have in your daily fare. And, of course, medication is a biggie: drugs can rob your body of valuable nutrients as well as play havoc with your liver and your gut. A good nutritional therapist can help you there, especially if they have the ability to find out exactly what is wrong. A therapist who uses bioresonance testing can be invaluable. Have a look at this website: http://www.nutrivital.co.uk
to find a practitioner who does bioresonance testing near you.