Could it be having an effect on the medications you take?  There really is no reason for this, and if you look at old cookbooks, you see that there was a lot of food made with gelatin.  I only take very small amounts, so I haven't seen that effect.  I had tendonosis in the right shoulder, and that only got resolved after eating more protein AND including daily gelatin supplements (though as I said, in very small amounts).  Also, my fingernails were soft, but now are hard and "snappy" when I clip them.