white spots

HEy, I don't know what the white spots on fingernails mean, but I had a few for the past few weeks. on 2-3 nails. I put nail polish on like 4 days ago, and now when I took it of, the spots weren't there anymore. I think it was something psychical, coz I am feeling better now mentally, and I think I ate more than before, because I wasn't so depressed. And the spots are gone. Very interesting! for me at least. and I am very glad I don't have spots on my nails anymore..they made me quite worried actually, coz when you see them, you know there's something wrong with you..you just never know what...