Role: Regulates cell growth and cell death. Growth/maintenance of bones/teeth; skin, mucous membranes, and other epithelial cells. Required for reproduction, immune function, vision/night vision, wound healing.
Deficiency: Eyes: night blindness, Bitot’s spots (foamy deposits on cornea), keratomalacia (corneal dryness, itching), progressing to xerophthalmia (corneal scarring and degeneration, blindness).
Skin, mucous membranes: hyperkeratosis (bumpy dry skin from clogged hair follicles); compromised linings of respiratory, digestive, and reproductive systems. Impaired immunity, growth, and reproduction.
Sources: liver, egg yolk, butterfat, cream, spinach, collards, and other dark-greens
Toxicity: Teratogenic (birth defects from excessive use during pregnancy), dry itchy skin. Hair loss. Bone/joint pain. Bone abnormalities. Loss of appetite. Liver damage.