1. Vitamins: Vital Keys to Health
BIOL 103, Chapter 9

2. Today’s Topics Understanding Vitamins
Fat Soluble Vitamins: A, D, E, K, and Carotenoids
The Water-Soluble Vitamins: Eight Bs and a C
Bogus Vitamins

3. Understanding Vitamins
Needed in small amounts
Not an energy source
Individual units
Organic compounds essential for normal functioning, growth, and maintenance of the body.

4. Understanding Vitamins
Fat soluble vs. water-soluble
Fat-soluble: vitamins A, D, E, K
Absorbed with fat, with lymphatic system
Stored in larger quantities
Water-soluble: 8 B vitamins and vitamin C
Absorbed into the bloodstream
Stored in small amounts
Which is more vulnerable to cooking losses?

5. Understanding Vitamins
Food preparation affections vitamin content in the foods
Factors that determine amounts:
Source
Sunlight
Moisture
Growing conditions
Plant’s maturity at harvest
Packaging and storage

6. Understanding Vitamins
Vitamins in foods
Enrichment and fortification
Enriched: replacing lost nutrients
Fortified: adding extra nutrients to foods
Some is required by law
Provitamins
_____________________ forms of vitamins

7. Vitamin A: The Retinoids
Functions
Vision, cell development and health, immunity
Food sources
Preformed vitamin A: liver, milk, egg yolks
Beta-carotene: yellow/orange fruits and vegetable

8. 4 Forms of Vitamin A
Three active forms of Vitamin A, collectively known as Retinoids:
Retinol
Retinal
Retinoic acid
Carotenoids are provitamins: _____________ of vitamin A

9. Functions of Vitamin A Vision: night and day
Night and color vision
Becomes part of the retina
Cell production and differentiation
Help make cells, enzymes, proteins
Cell differentiation: stem cells  specific cells
Skin
Required to replace epithelial cells of your skin

10. Functions of Vitamin A (cont.)
Immune Function
Produce immune cells to fight microorganisms
Reproduction
Keeps reproduction tracts healthy
Embryo development
Bones
Bone “remodeling”
Increase in osteoclasts

11. Vitamin A Dietary Recommendations Sources of vitamin A
Retinol activity equivalent (RAE) = 1 ug retinol
Uses RAE to account for differences between retinoids and carotenoids
Sources of vitamin A
__________: retinoids
__________: provitamin A carotenoids
Fortified foods

12. Vitamin A Deficiency Eyes The skin and other epithelial cells
Xerophtalmia
The skin and other epithelial cells
Hyperkeratosis
Immune function
Vulnerable to infection
Other effects:
Growth retardation, bone deformities, defective teeth, kidney stones

13. Vitamin A Toxicity Symptoms: Teratogen Discoloration of skin
fatigue, vomiting, abdominal pain, bone and joint pain, loss of appetite, skin disorders, headache, blurred or double vision, and liver damage
Teratogen
Discoloration of skin
Acne Treatment:
Retin-A and Accutane

14. The Carotenoids Plant pigments (deep yellow, orange, red color)
Can be converted to vitamin A
Beta-carotene supplies the most vitamin A of the carotenoids.
Functions:
Vision
Lower risk of certain cancer

15. The Carotenoids Food sources:
____________________fruit and vegetables (tomatoes, apricots, carrots), dark green vegetables
Absorb 20-40% of what we eat
Dietary fat and cooking with heat (breaks down cell walls) increases absorption

16. Vitamin D Forms and formations Activated in liver and kidney Functions
In the skin, UV light converts a form of cholesterol to D3  to liver  kidneys  active form: 25-hydroxyvitamin D [25(OH)D] or calcitrol
Functions
Essential for bone health
Regulate blood calcium levels

17. Vitamin D
Sources:
Sun exposure helps activate an inactive form of vitamin D
Fortified milk/foods
Oily fish, egg yolk, butter, liver
Question: Why would manufacturers choose milk to be fortified with vitamin D?

18. Problem Set 9 Question #1
Name at least three reasons why people around the world will not have similar levels of vitamin D.

19. Vitamin D Deficiency: Toxicity In children: In adults:
Rickets
In adults:
Osteomalacia or “soft bones”
Osteoporosis
Toxicity
Hypercalcemia: a high concentration of calcium in blood  excess deposit of calcium in soft tissues
(Stones, Bones, Groans, Thrones, Psychiatric overtones)

20. Melanin, Sunscreens and UV Light
Melanin, Chemical Sunscreen = Absorb UV
Physical Sunscreen = Reflect UV

21. Vitamin E Forms Functions 8 similar compounds
Essential: alpha-tocopherol
Stored mainly in _____________________.
Functions
Antioxidant
Protects cell membranes from free radicals

22. Vitamin E Food sources Deficiency Toxicity
Nuts, seeds, vegetable oil, whole grain, wheat germ oil, fruit, vegetables, and animal products
Deficiency
Occurs with fat malabsorption
Rare genetic disorder
Toxicity
Nontoxic and adverse effects have not been found
Can interfere with blood _____________

23. Vitamin K Forms: Functions: Food sources; K1 K2
_____________________ (also requires calcium)
Bone formations
Food sources;
Green vegetables (spinach, broccoli, brussel sprouts), plant oils, intestinal bacteria

24. Vitamin K Deficiency Toxicity Rare in healthy people
Newborn baby at risk
Toxicity
Can interfere with anticoagulant medications
Toxicity is rare

25. Summary of Fat-Soluble Vitamins

26. The Water-Soluble Vitamins: Eight Bs and a C
Primarily coenzymes
Antioxidants
What to keep in mind about each vitamins:
Function
Food sources
Toxicity vs. Deficiency

27. Vocabs to Know:
Coenzyme: a small compound that helps enzymes in biochemical reactions. Most coenzymes are derived from vitamins or are made from vitamins.
Energy Metabolism: process of generating energy from nutrients (glucose, fatty acids, amino acids).
Glycogen Metabolism
Fat Metabolism
Protein Metabolism

28. Thiamin/B1 Functions: Food sources:
Part of the coenzyme: thiamin pyrophosphate (TPP):
Power protein and fatty acid synthesis
Breaks down glucose  energy
Food sources:
Pork, legumes, nuts and seeds, fish and seafood, enriched grain product
Cooking ____________________ content

29. Thiamin/B1 Deficiency/”Ariboflavinosis”: Toxicity:
Can be caused by chronic alcoholism and poor diet
Beriberi: overall profound muscle weakness and nerve destruction  can’t stand up
Toxicity:
None reported

30. Riboflavin/B2 Functions: Food sources: Toxicity: UL is not set
Coenzyme in energy metabolism
Supports antioxidant activity
Food sources:
Milk and dairy products
Enriched grains, eggs
Toxicity: UL is not set

31. Milk Packaging
Light breaks down riboflavin easily, so foods high in riboflavin are stored in opaque containers.
That’s why it’s rare to see milk in bottles…

32. Niacin/B3 Functions: Food sources: Coenzyme in energy metabolism
Supports fatty acid synthesis
Food sources:
Can be made from tryptophan.
Need B1, B6, and iron to convert to B3
Whole and enriched grains
Meat, poultry, fish, nuts, peanuts

33. Niacin/B3 Deficiency: Toxicity Pellegra: “rough skin”
Four D’s: dermatitis, diarrhea, dementia, and death
Can worsen if also deficient in ____, ____, and iron.
Toxicity
Side effects: skin flushing, liver damage

34. Pyridoxine/B6 Functions: Food sources:
_______, coenzyme in protein and amino acid metabolism, gluconeogenesis (AA  glucose)
Produce neurotransmitters
Helps to lower blood levels of homocysteine  reduce risk for heart disease
Diagram:
Food sources:
Meat, fish, poultry, potatoes, bananas, sunflower seeds

35. Pyridoxine/B6 Deficiency Toxicity Microcytic hypochromic anemia
Can also be caused by deficiency in iron.
Damage nervous system  depression, headaches, confusion, convulsions.
Toxicity
Can cause subtle neurological damage
Other symptoms: upset stomach, headaches, sleepiness, tingling/prickling or burning sensation

36. Folate/B9 Functions: Food sources:
Coenzyme in DNA synthesis and cell division
Coenzyme in amino acid metabolism
Needed for normal red blood cell maturation
Works with B6 and B12 to help control homocysteine levels
Food sources:
Fortified cereals, enriched grains
Green, leafy vegetables

37. Folate/B9
Deficiency:
Megaloblastic anemia RBC cannot form ______  cannot ________  remain large, immature cells  cannot carry oxygen properly  anemia
Birth defects in the Neural Tube: _____________________
Heart disease from elevated homocysteine levels

38. Folate/B9
Toxicity:
Can mask vitamin B12 deficiency when you take folate supplements until nerve damage is irreversible.
In rare cases, some may suffer hives or respiratory distress

39. Cobalamin/B12 “Cobalt-containing compounds” (cobalamin) Functions:
Needed for normal folate functions
DNA and red blood cell synthesis
Metabolize homocysteine
Maintains myelin sheath around nerves  nerves protection
Food sources:
Only animal foods: meats, liver, milk, eggs
Some fortified foods

40. Cobalamin/B12 Absorption: Deficiency: Toxicity:
Requires adequate stomach acid and intrinsic factor
Deficiency:
Can be caused by Pernicious anemia: autoimmune disorder that damages stomach linings  reduced B12 absorption
Nerve damage
Toxicity:
No UL set

41. Pantothenic Acid/B5 Function: Food sources: Deficiency/Toxicity: Rare
Component of coenzyme A  extract energy from nutrients and help build fatty acids
Food sources:
Widespread in foods
Reduced by freezing, canning, refining
Deficiency/Toxicity: Rare

42. Biotin/B7 Functions: Food sources: Deficiency and Toxicity are rare
Acts as a coenzyme in:
Amino acid metabolism (amino acids  glucose)
Fatty acid synthesis
Food sources:
Cauliflower, liver, peanuts, cheese
Protein avidin (raw egg whites) binds biotin and prevents absorption
Deficiency and Toxicity are rare

43. Vitamin C Functions: Food sources: Antioxidant
Needed for collagen synthesis
Enhances the absorption of iron from plant foods
Food sources:
Fruits: citrus, strawberries, kiwi
Vegetables: broccoli, tomatoes, leafy green, potatoes

44. Vitamin C Deficiency: Toxicity: Scurvy May cause GI distress
For some people: kidney stones, iron toxicity

45. Summary of Water-soluble Vitamins

46. Choline: A Vitamin-Like Substance
Function:
Act as a catalyst to help metabolize homocysteine
Food sources:
Milk, liver, egg yolk, peanuts; overall is abundant in food
Deficiency: Unlikely in healthy people
Toxicity:
Diarrhea, falling blood pressure, fishy body odor

47. Bogus Vitamins
Bogus vitamins: Unnecessary substances found in some supplements
Examples: hesperidin, para-aminobenzoic acid (PABA), pangamic acid, rutin
Think twice before you buy them!