Nail Colors: What Do They Indicate?

The shape and color of nails, along with other factors, can signal a deterioration in health that may require a consultation with a general practitioner. Experts state: "Pale nails, for example, may reveal the presence of anemia, nutritional deficiencies, heart or kidney diseases, or even poisoning. White nails can indicate liver problems, while yellow nails suggest a fungal infection." Blue-tinged nails may point to a lack of oxygen in the body, while wavy nails can be an early sign of psoriasis or inflammatory arthritis. Swollen nail folds may be caused by allergens or fungi, and dark lines under the nail may be associated with skin cancer or infectious diseases. Health experts have also identified a specific nail shape known as clubbing (an increase in thickness of the skin under the fingernails or toenails), which can be caused by heart and lung diseases. Nail clubbing often occurs gradually and may be difficult to detect initially. It can result from the presence of large cells, called giant cells, in the small blood vessels in the fingertips.