Arsenic poisoning is the cause. The nail separates from the nail bed. Pitting Small pits or depressions. Most common nail problem seen in 25 percent to 50 percent of people with psoriasis. Spoon nails Soft nails that look scooped out.
Depression is usually large enough to hold a drop of liquid.
Often indicates iron deficiency anemia. Terry's nails Your nail looks opaque and white, but the nail tip has a dark pink to brown band. May accompany cirrhosis, congestive heart failure, adult-onset diabetes, cancer or aging. Narrow ridges that run the length of your nails. May appear in adulthood and become more obvious as you age.