my whole life i have had white spots on my finger nails. they grow
down from the cuticle. where do they come from? i have heard a lack of
calcium, an excess of calcium, trama (hitting my fingers on
something), and air bubbles when the nail is forming.

Hello!
First, a disclaimer:  I'm not a doctor, nor do I play one on TV.
That said, there is quite a bit of information about white spots on
the fingernails, formerly known as "leukonychia."  The consensus is
that while there are many possible causes, the most common cause is
light trauma to the part of the nail where it is forming.  As the nail
grows out, the spots move with the growth.  This does sound familiar,
doesn't it?

Other possible causes:
Psoriasis
Eczema
Allergic reactions
A lack of zinc, or the presence of cirrhosis,  can also cause a
whitening of the nails.

Source:
WebMD, "What Are These White Spots?"
http://my.webmd.com/question_and_answer/article/1689.50294
(The dermatologist answering this question suggests seeing a doctor if
you can't associate your white spots with injury.)

Other interesting sites:

American Academy of Dermatology, "Nail Health" (online pamphlet).
"White Spots - White spots on the nails are very common and usually
recur. These small, semi-circular spots result from injury to the base
(matrix) of the nail, where nail cells are produced. They are not a
cause for concern, and will eventually grow out."

Old Wives Tales (dispells some folklore about the spots)
 http://www.oldwivestales.net/QandAarticle1029.html

CoolNurse.com
http://www.coolnurse.com/nails.htm

TeenHeathFX
http://www.teenhealthfx.com/answers/health/Health-Illness-190.htm

I hope this answers your question, and gives you some peace of mind.

---

Clarification of Answer by bizguy-ga on 07 Nov 2002 10:54 PST

I'm sorry--I forgot to give you the URL for the online pamphlet from
the AAD.  It is:
http://www.aad.org/pamphlets/nailhealth.html