My nails tend to chip and crack when playing steel-string acoustic guitar. Cracking and ripping can be kept partially in-check by keeping my nails well-trimmed. However, a far worse problem is that the nail on my right index finger (that's my strumming hand) tends to wear down over time when I'm playing a lot. It's never worn away completely, but it gets uncomfortably thin.
Part of the problem is that I use fairly heavy strings--.013's. Another factor is undoubtedly my heavy right-hand technique when strumming.
Question: Is there any way I can prevent my nail from being shaved away, short of wearing gloves while playing?
I've seen stuff you can paint on your nails that's supposed to reinforce the nail, but it doesn't work very well. More calcium in my diet? (I already ingest a lot.) Is humidity a factor? Impure thoughts?
Clarification: This is happening when I use a pick.