White nails or toenails point towards a problem with the internal organs. Sometimes it's just a vitamin or mineral deficiency. Other times, it's a serious problem with the liver, heart, kidneys or pancreas.
I developed Terry's nails a little before I was diagnosed with diabetes. When I showed my doctor my white nails and toenails, he said that I need a thorough check up. Thankfully, my liver and kidney function results came back normal. But my blood sugar reading was too high.
I don't think that white toenails should be taken lightly. It's a good idea to get a check-up just in case.