Chapter 8 The Water-Soluble Vitamins Copyright © 2016 John Wiley & Sons, Inc. All rights reserved.

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. What Are Vitamins? Organic compounds essential in the diet to promote growth and health maintenance Water-soluble vitamins include the B vitamins and vitamin C B vitamins were originally thought to be one chemical substance but are actually many different substances, that is the reason for B1, B2, B12, etc. Fat-soluble vitamins include A, D, E and K Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 2

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. The Vitamins Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 3

Finding Vitamins in Foods Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 4

Fortified and Enriched Foods Fortification Process of adding nutrients to foods The added nutrients are generally not found in the food or are added in much larger amounts, such as fortifying orange juice with calcium Enrichment Adding nutrients back to foods that have lost nutrients due to processing An example is the addition of B vitamins to white rice Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 5

Fortified Foods: Enough or Too Much? Copyright © 2016 John Wiley & Sons, Inc. All rights reserved.

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Dietary Supplements Another source of vitamins in the modern diet Contain some combination of vitamins, minerals, herbs, botanicals, amino acids, enzymes or extracts Cannot replace the benefits of a diet containing a wide variety of foods Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 7

Absorption of Vitamins Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 8

Bioavailability of Vitamins Vitamins must be absorbed by the body in order to perform their functions Fat-soluble vitamins require fat in the diet to be absorbed Water-soluble vitamins may require transport molecules or specific molecules in the GI tract Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 9

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Storage and Excretion Water-soluble vitamins are easily excreted from the body (except B12) Because stores can be rapidly depleted, they must be consumed regularly Fat-soluble vitamins are stored in the liver and fatty tissue so it takes longer for a deficiency to develop Copyright © 2016 John Wiley & Sons, Inc. All rights reserved.

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Is Fresh Really Best? Copyright © 2016 John Wiley & Sons, Inc. All rights reserved.

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Vitamin Preservation Copyright © 2016 John Wiley & Sons, Inc. All rights reserved.

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Thiamin First B vitamin to be identified Also called vitamin B1 Assists in energy production, carbohydrate metabolism, the production of ribose and the health of the nervous system Beriberi—a deficiency of thiamin Wernicke-Korsakoff syndrome—a deficiency of thiamin in alcoholics Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 13

Thiamin: Dietary Sources Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 14

Thiamin Deficiency: Beriberi Copyright © 2016 John Wiley & Sons, Inc. All rights reserved.

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Riboflavin Easily destroyed by heat and exposure to light An important component in the citric acid cycle and for assisting the body with the absorption of other vitamins Flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN) are the coenzyme forms Ariboflavinosis—a deficiency of riboflavin Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 16

Riboflavin: Dietary Sources Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 17

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Niacin Can be synthesized in the body from the essential amino acid tryptophan if the diet is adequate in tryptophan Plays an important role in the production of energy and in general metabolism Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 18

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Niacin Pellagra—a niacin deficiency Symptoms include the 3 Ds: dermatitis, diarrhea and dementia, and eventually the 4th D: death Niacin toxicity from overuse of niacin supplements can result in elevated blood pressure, cardiac arrhythmia, nausea, vomiting, elevated blood sugar levels and impaired liver function Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 19

Niacin: Dietary Sources Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 20

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Biotin Biotin functions as a coenzyme in energy metabolism Avidin in raw eggs destroys biotin Dietary sources are liver, egg yolks, yogurt, and nuts Copyright © 2016 John Wiley & Sons, Inc. All rights reserved.

Pantothenic Acid: Dietary Sources Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 22

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Vitamin B6 Called pyridoxine and comprises a group of compounds including pyridoxal, pyridoxine, and pyridoxamine All three forms can be converted into pyridoxal phosphate, which is required for many enzyme reactions in the body Vitamin B6 deficiency may result in anemia due to impaired hemoglobin synthesis and neurotransmitter issues A toxicity from supplements can cause irreversible nerve damage Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 23

Vitamin B6: Dietary Sources Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 24

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. B6 and Myelin Copyright © 2016 John Wiley & Sons, Inc. All rights reserved.

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Folate (Folic Acid) Folate coenzymes are needed for DNA synthesis and the metabolism of some amino acids Low folate intake in early pregnancy is associated with an increased risk of neural tube defects Low folate intake has been associated with an increased risk of heart disease Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 26

Folate: Dietary Sources Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 27

Folate Deficiency: Macrocytic Anemia Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 28

Folate Deficiency: Neural Tube Defects Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 29

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Vitamin B12 Necessary for metabolism of folate and fatty acids and maintaining myelin around nerves Found almost exclusively in animal products Vegan diets require supplements or foods fortified with B12 High intake of folic acid can mask B12 deficiency Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 30

Vitamin B12: Dietary Sources Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 31

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Vitamin C Known as ascorbic acid or ascorbate Can be destroyed in food by oxygen, light and heat, as well as contact with copper or iron cookware Functions Antioxidant in the body Helps maintain the immune system Important in the production of collagen Aids in iron absorption Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 32

Vitamin C: Dietary Sources Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 33

Vitamin C Function: Collagen Copyright © 2016 John Wiley & Sons, Inc. All rights reserved.

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Vitamin C Scurvy—vitamin C deficiency UL is 2000 mg Copyright © 2016 John Wiley & Sons, Inc. All rights reserved.

Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. Chapter 8 Copyright 2016 John Wiley & Sons, Inc. All rights reserved. Reproduction or translation of this work beyond that permitted in section 117 of the 1976 United States Copyright Act without express permission of the copyright owner is unlawful. Request for further information should be addressed to the Permissions Department, John Wiley & Sons, Inc. The purchaser may make back-up copies for his/her own use only and not for distribution or resale. The Publisher assumes no responsibility for errors, omissions, or damages caused by the use of these programs or from the use of the information herein. . Copyright © 2016 John Wiley & Sons, Inc. All rights reserved. 36