In the soles of my feet, the underside of my toes feel spongy, but they are not actually spongy when I touch them. There is no swelling, no infection, nothing except I feel as if there is a layer of soft material under my toes. I was told it is vit D deficiency, but I have been on vit D from before this episode and in fact my blood level, though still low, has increased considerably. I did not have this problem when my Vit D was really low, but it has started in the last 1 year.