Biochemical signs of malnutrition include low levels of total plasma proteins, serum albumin, thyroxine binding globulin, prealbumin, transferrin, ceruloplasmin, retinol-binding protein, lymphocytes, water-soluble (B2, B12, B9, C) and liposoluble (A, D, E) vitamins, and trace elements (copper, selenium, zinc, iron, calcium) [40]. Here, TTR is linked to malnutrition.