UNIT 5 SEMINAR NS 220

Module 5: Vitamins and Health

Overview

Vitamin Supplementation

Vitamin deficiency diseases & food fortification

Beneficial vitamins for specific populations

Vitamin toxicities

Multivitamins

Position of American Dietetic Assoc.

To promote health and reduce risk of chronic

disease, choose variety of foods.

Food provides all vitamins you need.

Fortified foods and supplements can help some

meet their nutrition needs.

Vitamin Types

Vitamin C B Vitamins:

Folate B12 Thiamin Riboflavin Niacin Biotin Pantothentic Acid

Vitamin A Vitamin D Vitamin E Vitamin K

Water-Soluble Fat-Soluble

Vitamin Deficiencies

Vitamin A: may result in xerophthalmia

Vitamin D: rickets and osteomalacia

Vitamin K: deficiency in newborns; made in intestines by good bacteria

Vitamin C: scurvy; delayed wound healing; decrease in iron absorption; capillary bleeding

Thiamin: beriberi; heavy alcohol consumption can lead to poor absorption of thiamin

Dietary Guidelines

Nutrients consumed should come primarily from food.

Beneficial Vitamins for Specific Populations: Women and Folic Acid

Special Groups and Vitamin D

People Over 50 and Vitamin B12

Women and Folic Acid

Necessary for all women of

childbearing age and women who are pregnant.

Reduces the risk of neural tube defects and Spina Bifida.

Food fortification & food sources (green leafy vegetables)

RDA: 400 mcg (adults/women childbearing age); 600 mcg (pregnancy)

Special Groups & Vitamin D

Fat-soluble; obtain from food and sun Sun source activated in liver & kidney Deficiency diseases: Rickets & Osteomalacia Food sources: fortified milk most reliable source High risk of deficiency:

Breastfed infants Older adults Limited sun exposure Individuals with dark skin

People >50 & Vitamin B12

Most adults meeting recommended amounts

Deficiency most likely to occur as a result of an inability to absorb B12 from food.

B12 needs stomach acid & Intrinsic Factor to be absorbed; less gastric secretions over age 50, so decrease in absorption.

Recommend for >50 years old to eat fortified B12 foods or take supplement.

Natural source B12 only in animal foods.

Toxicities

>100% of RDA could be harmful to health for specific vitamins, esp from supplements.

Fat-soluble more risk of toxicity than water-soluble. Vit. A toxicity more likely from

high dosage vit A supplements.

UL’s established.

Multivitamins

NIH Consensus and State-of-the-Science Conference on Multivitamin/Mineral Supplements and Chronic Disease Prevention (2006) with results indicating: There is not strong evidence for beneficial health-

related effects of supplements. There is insufficient evidence to recommend either for

or against the use of multivitamin/mineral supplements by the American public to prevent chronic disease.

NIH State-of-the-Science Conference Statement on Multivitamin/Mineral Supplements and

Chronic Disease Prevention. Ann Intern Med. 2006;145:364–371.

MVI Use & Risk of CA and CVD

161, 808 post-menopausal women; 8 year study

41.5% participants used MVI’s

Results: convincing evidence that MVI use has little or no influence on the risk of common cancers, CVD, or total mortality

Marian L. Neuhouser et al. Multivitamin Use and Risk of Cancer and Cardiovascular

Disease in the Women's Health Initiative Cohorts. Archives of Internal Medicine, Feb 9,

2009.