1. The Water-Soluble Vitamins: B Vitamins and Vitamin C
Chapter 10

2. The Vitamins – An Overview
Vital to health, organic, and available in foods
Vitamins differ from macronutrients
Structure
Function
Food contents
Both deficiency and excess of vitamins can affect health

3. The Vitamins – An Overview
Bioavailability
Quantity provided by food
Amount absorbed and used by body
Factors influencing bioavailability

4. The Vitamins – An Overview
Precursors
AKA Provitamins
Organic nature
Can be destroyed during storage and in cooking

5. The Vitamins – An Overview
Solubility
Affects absorption, transport, and excretion
Water-soluble (B vit & vit C) VS Fat-soluble
Consumption frequency of vitamins

6. The Vitamins – An Overview
Toxicity
More is not necessarily better
Excessive intakes

7. The B Vitamins – As Individuals
Very active in the body, but do not provide the body with fuel for energy.
Several B vits form part of the coenzymes
Others participate in metabolism and cell multiplication.
Recommendations for B vits come from RDA, AI, and Tolerable Upper Intake Levels.
deficiencies, toxicities, and food sources are unique for each

8. The B Vitamins – As Individuals

9. The B Vitamins – Thiamin
Part of coenzyme thiamin pyrophosphate (TPP)
Energy metabolism
Nerve activity and muscle activity
Recommendations:
RDA Men: 1.2 mg/day.
RDA Women: 1.1 mg/day.

10. The B Vitamins – Thiamin
Deficiency
Malnourished and alcoholics
Deficiency symptoms:
Enlarged heart and possible cardiac failure.
Muscular weakness.
Apathy, poor short-term memory, confusion, and irritability.
Anorexia and weight loss.
Wernicke-Korsakoff syndrome is a severe deficiency that develops in those who abuse alcohol.
Deficiency results in the disease beriberi (dry & wet)
Toxicity
None reported

11. The B Vitamins – Thiamin
Food sources:
Whole-grain, fortified or enriched grain products
Moderate amounts in all foods
Pork
Other Information:
easily destroyed by heat)
Leaches into water
Steaming and microwaving

12. The B Vitamins – Thiamin

13. The B Vitamins – Riboflavin
Riboflavin (Vitamin B2):
Involved in energy metabolism.
Coenzyme forms:
Flavin mononucleotide (FMN) & flavin adenine dinucleotide (FAD)
Recommendations
RDA Men: 1.3 mg/day; Women: 1.1 mg/day
Deficiency
Inflammation of membranes
Deficiency symptoms
Deficiency disease is ariboflavinosis.
Toxicity
No reported toxicities

14. The B Vitamins – Riboflavin
Food sources
Milk and milk products, including yogurt and cheese
Whole-grain, fortified, and enriched grain products
Liver
Destruction of riboflavin
Destroyed
Not destroyed by cooking

15. The B Vitamins – Riboflavin

16. The B Vitamins – Niacin(Vitamin B3)
Two chemical structures
Nicotinic acid
Nicotinamide
Two coenzyme forms – metabolic reactions
Nicotinamide adenine dinucleotide (NAD)
NADP (the phosphate form)

17. The B Vitamins – Niacin RDA is stated in niacin equivalents
Recommendations
Body manufacturers from tryptophan
RDA is stated in niacin equivalents
RDA Men: 16 NE/day.
RDA Women: 14 NE/day.
Upper level of 35 mg/day for adults.

18. The B Vitamins – Niacin Deficiency Toxicity Pellagra
Symptoms Deficiency symptoms:
Toxicity
Supplements or drugs
Niacin flush
Toxicity symptoms
Potential health benefits of large doses of nicotinic acid:

19. The B Vitamins – Niacin Food sources Other Information
Milk, eggs, meat, poultry, and fish
Whole-grain and enriched breads and cereals
Nuts and all protein-containing foods
Other Information
Also called nicotinic acid, nicotinamide, and niacinamide.
The amino acid tryptophan is the precursor.
The vitamin can be lost from foods when it leaches into water.

20. The B Vitamins – Niacin

21. The B Vitamins – Biotin
As part of a coenzyme used in energy metabolism
Coenzyme that carries activated carbon dioxide
Critical in TCA cycle
Participates in gluconeogenesis and fatty acid synthesis
Participates in breakdown of fatty acids and amino acids

22. The B Vitamins – Biotin Recommendations – AI Adults: 30 g/day.
Deficiency and Toxicity
Deficiencies are rare.
Deficiency symptoms:
No reported toxicities.

23. The B Vitamins – Biotin
Biotin can be bound with an egg-white protein called avidin.
Food Sources:
Widespread in foods.
Organ meats, egg yolks, and fish.
Soybeans.
Whole grains.
Biotin can also be synthesized by intestinal bacteria.

24. The B Vitamins – Pantothenic Acid
Part of chemical structure of coenzyme A, used in E metabolism
Recommendations
AI: Adults 5mg/day
Deficiency
Rare
Symptoms:

25. The B Vitamins – Pantothenic Acid
Toxicity
None reported
Food sources (Widespread in foods):
Chicken, beef, liver, and egg yolks.
Potatoes, tomatoes, and broccoli.
Whole grains and oats.
Can be destroyed by freezing, canning, and refining.

26. The B Vitamins – B6
Three forms: Pyridoxal, pyridoxine, and pyridoxamine
Recent research claiming influence on cognitive performance, immune funx, steroid hormone activity.
Stored exclusively in muscle tissue

27. The B Vitamins – B6 Recommendations Deficiency
Adults (19-50yrs): 1.3mg/day
Deficiency
Symptoms:
Alcohol destroys the vitamin.
Isoniazid (INH) drug used for tuberculosis acts as an antagonist.

28. The B Vitamins – B6 Toxicity Upper level for adults: 100 mg/day.
Food sources
Meats, fish, poultry, and liver
Legumes and soy products
Non-citrus fruits
Fortified cereals, potatoes and other starchy vegetables.

29. The B Vitamins – B6

30. The B Vitamins – Folate Known as folacin or folic acid
Primary coenzyme form – THF (tetrahydrofolate)
Transfers single-carbon compounds during metabolism

31. The B Vitamins – Folate Recommendations
RDA Adults: 400 g/day.
Dietary Folate Equivalents (DFE)
Higher recommendations for pregnant women.
Folate and Neural Tube Defects
Pregnant women should take folate supplements.

32. The B Vitamins – Folate Folate and Heart Disease
High levels of homocysteine and low levels of folate increase risk of heart disease.
Folate breaks down homocysteine.
Folate may help to prevent cancer, but may also promote cancer growth once cancer has developed.

33. The B Vitamins – Folate Deficiency
Elevated homocysteine levels.
Most vulnerable of all the vitamins to interactions with medications.
Toxicity
Masks vitamin B12 deficiency symptoms.

34. The B Vitamins – Folate Toxicity: Food Sources
Upper level for adults: 1000 g/day.
Food Sources
Fortified grains
Leafy green vegetables
Legumes and seeds
Liver
Easily destroyed by heat and oxygen.

35. The B Vitamins – Folate

36. The B Vitamins – Vitamin B12
Cobalamin –
Methylcobalamine and deoxyadenosylcobalamin are the coenzyme forms.
Recommendations
RDA Adults: 2.4 g/day.

37. The B Vitamins – Vitamin B12
Deficiency symptoms
Anemia
Fatigue and degeneration of peripheral nerves progressing to paralysis.
Sore tongue, loss of appetite, and constipation.
Deficiency disease is called pernicious anemia.

38. The B Vitamins – Vitamin B12
No known toxicities
Food Sources.
Meat, fish, poultry, and shellfish.
Milk, cheese, and eggs.
Fortified cereals.
Other Information
Binds with intrinsic factor
Easily destroyed by microwave cooking.

39. The B Vitamins – In Concert
Each B vitamin coenzyme is involved in energy metabolism
Directly
Indirectly
Deficiencies
Single B-vitamin deficiencies seldom show up in isolation

40. The B Vitamins – In Concert
The B Vitamins are interdependent
Presence of one may affect the absorption, metabolism, and excretion of another.
A deficiency of one may affect the functioning or deficiency of another.
A variety of foods from each food group will provide an adequate supply of all the B vitamins.

41. The B Vitamins – In Concert
B Vitamin Roles
Coenzymes involved directly or indirectly with energy metabolism.
Facilitate energy-releasing reactions.
Build new cells to deliver oxygen and nutrients for energy reactions.
B Vitamin Deficiencies
Deficiencies rarely occur singly except for beriberi and pellagra.
Can be primary or secondary causes.
Glossitis and cheilosis are two symptoms common to B vitamin deficiencies.
Symptoms that individuals experience are not necessarily related to a vitamin deficiency.

42. The B Vitamins – In Concert
B vitamin toxicities can occur with supplements.
B Vitamin Food Sources
Grains group provides thiamin, riboflavin, niacin and folate.
Fruits and vegetables provide folate.
Meat group provides thiamin, niacin, vitamin B6, and vitamin B12.
Milk group provides riboflavin and vitamin B12.

44. The B Vitamins – In Concert

45. Vitamin C – Roles Antiscorbutic factor is the original name Roles
Serves as a cofactor to facilitate the action of an enzyme
Antioxidant
As a Cofactor in Collagen Formation

46. Vitamin C Needs increase during body stress,
As a Cofactor in Other Reactions
Hydroxylation of carnitine
Converts tryptophan to neurotransmitters
Makes hormones
Needs increase during body stress,
i.e. infections, burns, extremely high or low temperatures, heavy metal intakes, certain medications, and smoking

47. Vitamin C Vitamin C Recommendations Deficiency
In the Prevention and Treatment of the Common Cold
Role in disease prevention is still being researched
Vitamin C Recommendations
RDA Men: 90 mg/day; Women: 75 mg/day
Smokers: +35 mg/day
Deficiency
Disease is called scurvy
Deficiency symptoms

48. Vitamin C – Deficiency

49. Vitamin C Toxicity Food Sources Other information
Upper level for adults: 2000 mg/day
Food Sources
Citrus fruits, cantaloupe, strawberries, papayas, and mangoes
Cabbage-type vegetables, dark green vegetables like red peppers and broccoli, lettuce, tomatoes, and potatoes
Other information
Also called ascorbic acid
Easily destroyed by heat and oxygen

50. Vitamin C – Food Sources