Soft, pink, tender nails that are easily bent are indication of a Pitta constitution. When the nails are thick, strong, soft and very shiny, then Kapha predominates. Longitudinal lines on the nails indicate mal-absorption in the digestive system. Transverse grooves on the nails may indicate the presence of long-standing illness or malnutrition. Yellow nails indicate a delicate liver or jaundice.
Blue nails are manifestation of a weak heart.
Undue redness shows an excess of red blood cells.