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Lecture Discovering nutrition - Chapter 7: Vitamins

After studying this chapter you will be able to understand: Understanding vitamins; fat-soluble vitamins A, D, E, K, and the carotenoids; vitamin A: the retinoids; the carotenoids; vitamin D; vitamin E;. | Chapter 7 Vitamins: Vital Keys to Health 1 Understanding Vitamins Vitamins Needed in small amounts Not an energy source Individual units rather than long chains Essential for normal functioning, growth, and maintenance of the body 2 Understanding Vitamins Fat-soluble vs. water-soluble Fat-soluble: Vitamins A, D, E, K Absorbed with fat into lymphatic system Stored in larger quantities Less vulnerable to cooking losses Water-soluble: B Vitamins and Vitamin C Absorbed into bloodstream Stored in small amounts Vulnerable to cooking losses 3 Understanding Vitamins Food preparation affects vitamins in foods Vitamins found in all food groups Factors that determine amounts Source (animal vs. plant) Sunlight Moisture Growing conditions Plant’s maturity at harvest Packaging and storage 5 Food preparation affects vitamins in foods Enrichment and fortification Enrichment—replacing lost nutrients in processed foods Fortification—adding extra nutrients to foods that wouldn’t have them naturally Some is required by law Understanding Vitamins 6 Food preparation affects vitamins in foods Provitamins Inactive Body must change them to active form Example: beta-carotene Understanding Vitamins 7 Vitamin A: The Retinoids Forms of Vitamin A Active forms (retinoids) Retinol Retinal Retinoic acid Precursors (carotenoids) 8 Vitamin A: The Retinoids Functions Vision Maintaining healthy cells Fighting infections and bolstering immune function Promoting growth and development Cell development and health 9 Vitamin A Functions of vitamin A Vision: night and day Changes incoming light to visual images Keeps eye’s surface healthy Allows night and color vision 11 Vitamin A Functions of vitamin A Cell production and differentiation Regulates production of enzymes, blood carrier proteins, and structural proteins (like those in the skin) Skin Needed to replace epithelial cells 12 Vitamin A Functions of vitamin A Immune function Produce immune cells Reproduction Keep reproductive tracts healthy Bones . | Chapter 7 Vitamins: Vital Keys to Health 1 Understanding Vitamins Vitamins Needed in small amounts Not an energy source Individual units rather than long chains Essential for normal functioning, growth, and maintenance of the body 2 Understanding Vitamins Fat-soluble vs. water-soluble Fat-soluble: Vitamins A, D, E, K Absorbed with fat into lymphatic system Stored in larger quantities Less vulnerable to cooking losses Water-soluble: B Vitamins and Vitamin C Absorbed into bloodstream Stored in small amounts Vulnerable to cooking losses 3 Understanding Vitamins Food preparation affects vitamins in foods Vitamins found in all food groups Factors that determine amounts Source (animal vs. plant) Sunlight Moisture Growing conditions Plant’s maturity at harvest Packaging and storage 5 Food preparation affects vitamins in foods Enrichment and fortification Enrichment—replacing lost nutrients in processed foods Fortification—adding extra nutrients to foods that wouldn’t have them naturally .