White nails without blood is a sign of inadequate peripheral circulation in the extremities, mostly seen in anaemia and shock, when the body’s blood volume is reduced and the peripheral blood supply to the extremities is relatively reduced to ensure adequate blood supply to the vital organs (heart, brain, kidneys), resulting in pale skin, white nails and cold, wet extremities.
It may also be seen in people with Raynaud’s phenomenon, which is caused by spasm of the small arteries at the extremities and manifests as a change from pallor to bruising to flushing at the end of the limbs, often secondary to autoimmune connective tissue diseases such as systemic lupus erythematosus and rheumatoid arthritis.