presentation about B-Complex vitamins

1. Water Soluble Vitamins
Susan Algert

2. Water Soluble Vitamins
Thiamin Pantothenic Acid
Riboflavin Biotin
Niacin Vitamin C
Vitamin B-6
Folate
Vitamin B-12

3. Fat vs. Water Soluble Vitamins
Water Soluble Fat Soluble
Absorption Directly to
blood
Lymph via CM
Transport free Require carrier
Storage Circulate freely In cells with fat
Excretion In urine Stored with fat
Toxicity Possible w
supplements
Likely w
supplements
Requirements Every 2-3 days Every week

4. Water soluble vitamins
• Susceptible to heat
• Kidney removes and excretes excess
• Vitamin C, thiamin and riboflavin are
especially susceptible to heat and alkilinity
• Hydrophilic and water will leach them from
vegetables
• Preferred methods are steaming, stir-fry and
microwave

5. B vitamins act as co-enzymes

6. Thiamin
• Sulfur containing and nitrogen containing
rings attached to carbon atoms
• Part of nerve cell membranes—synthesize
and regulate neurotransmitters
• Functions in energy metabolism—vitamin
portion of TPP; plays role in
decarboxylation and helps form
Acetyl Co A from pyruvate

7. Thiamin
• Dietary Recommendation
RDA for adult men is 1.2 mg for women is 1.1
mg per day
Higher needs in pregnancy; most diets with
variety and adequate energy supply ample
thiamin

8. Thiamin
• Deficiency
• Heavy alcohol consumption with
inadequate food consumption ; alcohol
interferes with absorption (Wernicke-
Korsakoff syndrome); poor and elderly at
risk for not eating sufficient energy

9. Thiamin Deficiency/Toxicities
• Beri Beri
• Impaired muscle contractions
• Impaired cardiac function, edema and
muscle twitches
• Decreased neurological function and
memory loss

10. Thiamin food sources
• Pork
• Whole and enriched grains
• Fortified cereals
• Most animal foods contain little
thiamin

11. Riboflavin
• Involved in energy metabolism; part of two
co-enzymes, FMN and FAD
• Participate in citric acid cycle and beta
oxidation and electron transport
• Remove ammonia during deamination of
some amino acids
• Associated with antioxidant glutathione
peroxidase

12. Dietary Recommendations for
Riboflavin
• RDA is 1.1 mg for women and 1.3 mg for
men per day
• Pregnancy and lactation increase energy
needs and need for riboflavin

13. Food Sources
• Most plant and animal foods
• Milk and milk drinks and yogurt supply
about 15% in the American diet
• Fortified cereals, bread and bread products
contribute about 10%
• One of four vitamins added to enriched
products

14. Deficiency/Toxicity
• Deficiencies are rare although some people
may take in marginal amounts
• Drug and alcohol users and restricted
caloric intake
• Ariboflavinosis
• Toxicity– not observed

15. Niacin (Nicotinic Acid)
• Made from tryptophan; essential nutrient if
protein intake is inadequate
• 60 mg tryptophan converts to 1 mg niacin
• RDA is 14-16 NE/day for adults
• NE include preformed and niacin derived
from tryptophan

16. Functions of Niacin
• NAD and NADP play key role in
oxidation-reduction reactions
• Helps convert pyruvate to lactate
• Coenzyme component that
participates in over 200 metabolic
reactions

17. Food Sources
• Preformed niacin from meat, poultry fish
and enriched or whole grain products
• Beef and processed meats are substantial
contributors in U.S. diet
• Stable when heated
• Tryptophan found in protein rich animal
foods

18. Niacin deficiency
• Pellagra
• Epidemic in southwest in early 1900’s as
corn became staple; niacin is bound by
protein
• Deficiencies found in southeast if subsisting
on diet of corn, molasses and salt pork
• International health issue

19. Medicinal uses of niacin
• Lowers blood levels of LDL cholesterol
• Raises HDL cholesterol
• Doses of 1,300 mg to 3,000 mg per day
• Side effects include liver abnormalities
• UL for niacin is 35 mgms per day
• Taken only under medical supervision

20. Biotin
• Function critical in energy metabolism ;
TCA cycle and gluconeogenesis
• Bound to enzymes as a co-factor and
requirement is small
• No RDA; AI is 30 micrograms/day
• Deficiency rare and toxicity not seen

21. Pantothenic Acid
• Component of Co enzyme A; involved in
energy metabolism
• No RDA; AI is 5 mg/day
• Deficiency is rare (dermatitis, hair loss,
depression)
• Toxicity is rare

22. Vitamin B-6
• Forms include pyridoxal, pyridoxine, and
pyridoxamine and phosphorylated forms
• Functions include support of over 100
different enzyme reactions including :
transfer of amino group, carboxyl group or
water
Enzymes support protein metabolism, blood
cell synthesis, CHO metabolism,
neurotransmitter synthesis

23. Dietary Recommendations and
Sources
• RDA is 1-3 mg/day; TUL =100 mg/day
• Deficiency symptoms include weakness,
insomnia, depression, irritability
• Sources include fortified cereals, meat, fish,
poultry, starchy vegetables and noncitrus
fruits
• Heat sensitive; most people get enough

24. B6 Toxicity and Medicinal Use
• Megadoses of up to 2,000 mg/day can cause
irreversible nerve damage
• Large doses used to treat PMS or in stress
formulas
• UL is 100 mg/day
• High doses taken only under medical
supervision

25. Folate
• Converts vitamin B-12 to coenzyme form
• Supports DNA synthesis and cell replication
and growth
• Along with B12 and B6, may decrease risk
for heart disease
• Tetrahydrofolic acid (THFA) is coenzyme
with five active forms

26. Dietary Recommendations and
Deficiency
• RDA is 400ug/day (is it most prevalent
vitamin deficiency?)
• TUL is 1000 ug/day
• Deficiency causes macrocytic anemia, NTD
• Toxicity masks vitamin B12 deficiency
• Dietary folate equivalents= higher
bioavailability of supplemental folate vs.
folate in foods

27. Folate in foods
• Fortified ready to eat cereals
• Dark green leafy vegetables
• Asparagus
• Broccoli
• Orange juice
• Wheat germ
• Legumes

28. Vitamin B-12-Cyanocobalamin
• Cobalamin or cobalt containing compounds
• Transfers methyl group from folate
coenzyme THFA to make active form; B12
deficiency leads to folate deficiency
• Dietary recommendations 2.4 ugm/day for
men and women
• Atrophic gastritis decreases bioavailability
in adults over 51

29. Vitamin B-12 Absorption
• R-protein
• pancreatic enzymes
• Intrinsic factor
• Bacteria in the stomach
• Gastric acid production

30. B12 in the diet
• RDA is 2.4 ugm per day; B12 not present in
plant foods
• Animals store excess B12 in tissues
• Mixed foods with animal protein contribute
most B12
• B12 deficiency usually occurs due to
impaired absorption
• Vegans at risk

31. Deficiency disease is pernicious
anemia
• Megaloblasts and macrocytes rather than
normal red blood cells
• Brain abnormalities and spinal cord
degeneration which can be lethal
• Pernicious anemia attacks parietal cells and
diminishes intrinsic factor and stomach acid

32. Functions of Vitamin C
• Antioxidant—donates electron minimizing
free radical damage; Recycles oxidized
vitamin E for reuse
• Collagen synthesis
• Stabilizes reduced form of folate enzyme
• Enhances absorption of non-heme iron
• Helps synthesize carnitine
• Proper functioning of immune system

33. Vitamin C deficiency/toxicity
• Scurvy
• Breakdown gums and joints
• Bone pain, diarrhea, fractures, fatigue
• UL is 2,000 mg per day
• Can possibly enhance oxidation when
consumed in high doses without other
antioxidants

34. Dietary Recommendations
• RDA is 90 mg for men and 75 mg for
women per day
• Smokers require +35 mg per day
• Food sources include potatoes, citrus fruits,
broccoli, leafy greens
• Highly vulnerable to heat and oxidation

35. Vitamin like compounds
• Choline
• Inositol
• Carnitine
• Lipoic acid