NS 1150 Lecture Notes - Lecture 31: Sebaceous Gland, Vitamin A, Retinol

• School: Cornell University
• Department: Nutritional Science
• Course: NS 1150
• Professor: David Levitsky

Document Summary

Vitamin a (retinol) is an antioxidant: sources. Gets into epithelial cells in intestinal wall. Turn both forms into retinol (active form of vitamin a in body) Retinol is absorbed into veins and taken in liver. High stores of vitamin a in the liver. So eat liver good source of vitamin a. Retinal (in the eye) + opsin rhodopsin. When 1 photon hits rhodopsin protein on surface of nerves. Reading problems: suffering from insufficient light to dark. When vitamin a is low enough, night blindness: growth. Vitamin a deficiencies: foamy line of bitot spot, night blindness hardened cornea permanent blindness. Normal range: 500-3000 micrograms, too low (effects due to lower levels going down) Xeropthalmia (lack of tears) damage due to dry eye. Infection (immune system fails, vitamin a required for cells: too high. Role of vitamin a in epithelial functions: skin consists of epithelial cells, acne. 85% of population between 12-25 suffer from acne.