The Vitamins

1
The Vitamins
2
Classifying Vitamins

• Fat Soluble Vitamins
• A
• D
• E
• K

3
Water Soluble Vitamins

• Vitamin C
• B Vitamins
• Thiamin -- Biotin
• Riboflavin -- Pantothenic acid
• Niacin
• B6
• Folate (folic acid)
• B12

4
Water Soluble Vitamins

• Digestion, Absorption, and Transport
• No chemical digestion needed
• Absorbed in the SI into the capillaries
• Vitamin B12 must bind with a protein called the
  intrinsic factor (IF) in the stomach for
  absorption to occur in the SI
• No carriers required for transport in the blood

5
Water Soluble Vitamins

• Storage and excretion
• Travel freely in the blood
• Cells take up water soluble vitamins as needed
• Limited storage beyond tissue saturation
• Excess excreted in the urine

6
Water Soluble Vitamins

• Deficiency is more common than toxicity for the
  water soluble vitamins
• Why??
• Any toxicity is likely to be due to overuse of
  vitamin supplements, not food intake

7
Water Soluble Vitamins

• Other interesting information
• Many are destroyed by light, heat, or exposure to
  oxygen
• Best to cook whole in a minimum amount of water
• Why??
• Frozen vegetables are often higher in vitamin
  content than grocery store fresh veggies
• Why??

8
Fat Soluble Vitamins

• Digestion, Absorption, and Transport
• Bile needed to emulsify fat soluble vitamins
• Form chylomicrons (along with long chain fatty
  acids and monoglycerides)
• Chylomicrons are absorbed into the lacteals
• Travel through lymph system ? blood ? liver
• Many require protein carriers to be transported
  in the blood

9
Fat Soluble Vitamins

• Storage
• Stored in liver and fatty tissue
• Unlimited stores possible
• Greater risk of toxicity than deficiency for fat
  soluble vitamins
• Why??

10
Fat Soluble Vitamins

• Other interesting facts
• Found in the fatty parts of food
• Removed with the fat when low-fat products are
  made
• Many low-fat foods are supplemented with these
  vitamins to make up for this
• E.g. milk is vitamin A and D enriched

11
The Vitamins

• For each vitamin we will consider
• Functions
• Dietary needs and food sources
• Deficiency
• Toxicity

12
Thiamin

• History
• Functions
• Needed for energy metabolism
• E.g. -- required for conversion of pyruvate to
  acetyl CoA
• Needed for nerve and muscle function

13
Thiamin

• Recommended Intake
• 1.1-1.2 mg/day
• Food Sources
• Found in small amounts in many foods
• Easily destroyed by heat (cooking)
• Lost in cooking water
• Good sources include
• Pork products, soy, legumes, vegetables, whole
  grains, watermelon.(pg 327)

14
Thiamin Deficiency

• Prolonged deficiency leads to beriberi
• Results in damage to nervous system and muscles
  (to include the heart)

15
Thiamin Deficiency

• Symptoms Beriberi
• Dry form- muscle wasting, poor coordination
  Muscle weakness
• Legs heavy, hard to walk, calf pain
• Apathy, confusion, memory loss
• Anorexia and weight loss
• Wet form has additional symptoms of
• edema, irregular heart beat, enlarged heart

16

• In alcoholics thiamin deficiency results in
  Wernicke-Korsakoff syndrome.
• Symtpoms
• Mental confusion
• Staggering
• Rapid eye movements or paralysis of the eye
  muscles

17
Thiamin Deficiency

• Populations at risk
• Alcoholics
• See in alcoholics who obtain the majority of
  their calories from alcohol
• Alcohol inhibits thiamin absorption and hastens
  its excretion
• Cultures that eat primarily refined grains (and
  little else)
• Thiamin deficient moms ? infant deaths

18

• The City of New York
• DEPARTMENT OF HEALTH AND MENTAL HYGIENE
• Michael R. Bloomberg Thomas R. Frieden, m.d.,
  m.p.h.
• Mayor Commissioner
• __________________________
  _____________________________________
• nyc.gov/health
• 2003 Health Alert 39
• A cluster of infantile thiamine (vitamin B1)
  deficiency (beri-beri) has been reported in
  Israel among infants fed a vitamin B1-deficient
  kosher soy-based formula distributed by Remedia.
  It is possible that this product may be imported
  into New York City and there may be children in
  the Orthodox Jewish community who have consumed
  it.
• The New York City Department of Health and Mental
  Hygiene (NYCDOHMH) asks that providers report
  immediately any suspect case of thiamine
  deficiency among infants who have been fed this
  product to
• The New York City Poison Control Center at
• 1-212-764-7667 (212-POISONS) or 1-800-222-1222.
• Please distribute to Pediatric staff in the
  Departments of Cardiology, Critical Care,
  Emergency Medicine, Family Medicine, General
  Pediatrics, Outpatient Pediatrics, Neonatology,
  Neurology, and Infectious Disease

19
Thiamin

• Toxicity
• None known
• Excess thiamin is excreted and not stored

20
Riboflavin

• Functions
• Needed for the metabolism of carbohydrates, fats,
  and proteins
• Places a role in Krebs cycle
• Part of FAD

21
Riboflavin

• Recommended Intake
• 1.1 1.3 mg/day
• Food Sources
• Destroyed by ultraviolet light (sun light)
• Good sources include
• Milk and milk products
• Liver
• Whole grain breads and cereals, oatmeal
• Clams and squid!
• Mushrooms (page 329)

22
Riboflavin

• Deficiency Symptoms
• Eyes are inflamed and sensitive to light
• Cheliosis (cracks at the corners of the mouth)
• Sore throat
• Inflammation of the tongue and mouth painful
• Inflamed skin, with lesions covered with greasy
  scales
• Anemia

23
Riboflavin

• Populations at Risk for Deficiency
• alcoholics
• any one with a marginal diet
• Poor, elderly, eating disorders, drug addicts
• Toxicity
• None reported
• Excess excreted

24
Niacin

• Functions
• Plays an essential role in energy metabolism
• Part of NAD
• Needed by every cell of the body

25
Niacin

• Recommended Intake
• 14 16 mg/day of niacin or of NE
• NE Niacin Equivalents
• Niacin can be made from the essential amino acid
  tryptophan
• It takes 60 mg of tryptophan to make 1 mg of
  niacin
• Therefore, 1 NE is 60 mg of tryptophan

26
Niacin

• Food Sources
• Sources of complete protein
• Dairy, meats, poultry, fish,
• Peanut butter
• Tomato paste
• Mushrooms
• (page 332)

27
Niacin Deficiency

• Niacin deficiency disease is called pellagra
• Symptoms, 4 Ds
• Dermatitis with sun exposure (pg 330)
• Diarrhea, vomiting
• Dementia
• Death
• Other symptoms
• Inflamed, swollen, red, smooth tongue
• Loss of appetite

28
Niacin

• Pellegra - Other interesting information
• Originally believed to be caused by infection
• Common up to early 1900s in US and Europe
• Many in mental hospitals in south had niacin
  deficiency, not mental illness
• Incidence declined in US after WW II when
  mandatory enrichment of grains began
• Still common in Africa and Asia
• Poor bioavailability form corn unless its soaked
  in lime juice

29
Niacin

• Toxicity
• Tolerable Upper Intake Level (UL) 35 mg/day
• High doses of niacin are commonly used to treat
  high cholesterol
• 1500 -3000 mg/day recommended for treating high
  cholesterol

30
Niacin

• Toxicity Symptoms
• Niacin flush
• Excessive sweating
• Tingling
• GI distress
• Frequent need to urinate
• May mask prostrate cancer symptoms in men
• Blurred vision, headaches
• Liver damage

31
Folic Acid Folate

• Functions
• Needed for DNA synthesis
• Need to make all new cells
• E.g. Need to make new RBC
• Reduces incidence of neural tube defects
• Defects occur in first weeks of pregnancy

32
Folate

• Plays a role in protein synthesis
• Breaks down the amino acid homocysteine
• High levels of homocysteine increases risk of
  blood clot formation
• May reduce risk some cancers
• Pancreatic cancer in men who smoke
• Breast cancer in women who drink

33
Folate

• Absorption and Activation
• Folate in foods must be acted upon by an
  intestinal enzyme for it to be absorbed and
  transported to cells
• Folate in cells needs to be activated by vitamin
  B12
• Process also activates the B12

34
Folate

• Recommended intake
• 400 micrograms/day

35
Folate

• Factors impacting needs
• Pregnancy -600 mcg/day
• Aspirin, antacids, smoking, oral contraceptives
  reduce absorption
• Some cancer drugs reduce absorption
• GI tract damage reduces absorption
• Occurs with alcoholism, anorexia
• Poor absorption, leads to even more damage to GI
  tract

36
Folate

• Food Sources
• Cooking destroys up to 50 of folate
• Oxygen destroys folate
• Good sources include
• Green leafy vegetables
• Legumes
• Fortified cereals and Seeds
• Liver
• Orange juice (ok, but not great source) pg 341

37
Folate

• Folate Deficiency
• Impairs cell division and protein synthesis
• Symptoms
• Megaloblastic anemia
• Fewer red blood cells (RBC) made
• RBC larger than normal
• RBC do not carry oxygen as well

38
Folate Deficiency

• Confusion, irritability, weakness, fatigue
• Related to the anemia
• GI tract deterioration
• Elevated homocysteine levels
• Smooth red tongue
• Increased risk neural tube defects

39
Folate

• Toxicity
• No known symptoms
• May mask a vitamin B12 deficiency
• B12 deficiency is VERY serious

40
Vitamin B12

• Dorothy Crowfoot Hodgkin
• Awarded the Nobel prize in chemistry for deducing
  the structure of vitamin B12
• Took her eight years
• Headline in the London paper announcing this read
  
• Nobel Prize for British Wife

41
Vitamin B12

• Functions
• Needed to activate folate
• Therefore, needed for DNA and new cell (RBC)
  synthesis
• Helps maintain myelin sheath around nerve cells

42
Vitamin B12

• Recommended intake
• 2.4 microgams per day
• Food Sources
• ONLY found naturally in animal products
• Meat, poultry, fish, eggs, dairy, liver.
• Fortified grains
• Easily destroyed by microwave cooking

43
Vitamin B12

• Deficiency
• Pernicious anemia (VERY SERIOUS)
• Megaloblastic anemia
• Nerve damage ? creeping paralysis
• Smooth sore tongue
• Fatigue

44
Vitamin B12

• Pernicious anemia frequently goes undiagnosed
• Pernicious anemia can be masked by high intakes
  of folate

45
Vitamin B12

• Gastric by-pass patients and vegans are at
  elevated risk
• Takes several years to develop
• Toxicity
• None reported

46
B6

• Functions
• Need for protein and fatty acid metabolism
• Need for amino acid metabolism
• E.g. For converting tryptophan to other niacin
• need to make serotonin form tryptophan
• Helps make RBC
• Other functions under study

47
B6

• Recommended Intake
• 1.3 mg/day
• UL 100 mg/day
• Food sources destroyed by heat
• Meat, fish, poultry
• Legumes
• Seeds and nuts
• Liver
• Non-citrus fruits

48
B6

• Deficiency (rare)
• Anemia ? Weakness and fatigue
• Depression, confusion
• Abnormal brain waves, convulsions
• Greasy dermatitis

49
B6

• Increased risk of deficiency
• Alcoholics
• Alcohol contributes to increased B6 breakdown and
  excretion
• Oral contraceptives may increase risk of B6
• deficiency
• Drug INH inactivates B6
• INH used to treat tuberculosis

50
B6

• Toxicity Serious
• Stored in muscle cells, toxicity seen with
  supplements
• Symptoms
• Irreversible nerve damage ? numbness in hands and
  feet ? Difficult to walk
• Convulsions
• Insomnia, restlessness

51
B6

• B6 does not help with
• Carpal tunnel syndrome
• PMS
• Supplementation above the UL is NOT recommended

52
Biotin

• Functions
• Need for energy metabolism
• Need to make glycogen
• Plays a role in fatty acid and amino acid
  synthesis

53
Biotin

• Recommended Intake
• 30 micrograms/day (AI)
• Food Sources
• Widespread in foods liver, egg yolk, legumes,
  fish, mushrooms, whole grains
• Some produced by GI tract bacteria
• easily destroyed by processing

54
Biotin

• Deficiency
• RARE
• Skin rash
• Hair loss
• Depression
• Hallucinations
• Numbness in legs/arms

55
Biotin

• Deficiency can be induced by eating LARGE
  quantities of raw egg whites
• 2 dozen daily for 2 months!
• Prevents biotin absorption
• Toxicity none reported

56
Pantothenic Acid

• Functions
• Need for energy metabolism
• Part of acetyl CoA
• Plays a role in the synthesis of many substances
• Lipids
• Hormones
• Neurotransmitters
• Hemoglobin

57
Pantothenic Acid

• Recommended intake
• 5 mg/day (AI)
• Food Sources
• Widespread in foods

58
Pantothenic Acid

• Deficiency Rare
• Fatigue
• GI distress
• Insomnia, depression
• Apathy, irritable
• Increased sensitivity to insulin

59
Pantothenic Acid

• Toxicity none known

60
Vitamin C

• Functions
• Collagen synthesis
• Part of scar tissue
• Strengthens blood vessels
• Provides matrix for bone growth
• Antioxidant
• Need for healthy immune system
• Need for thyroxine production

61
Vitamin C

• Functions
• Need for thyroxine production
• Regulates body temperature and metabolic rate
• Enhances iron absorption
• Need to make hemoglobin

62
Vitamin C

• Recommended intake
• Men 90 mg/day
• Women 75 mg/day
• Smokers an extra 35 mg/day
• More free radicals that need to be neutralized
• UL 2000 mg/day

63
Vitamin C

• Food sources
• Citrus fruits
• Strawberries, melon
• Vegetables
• Tomatoes, dark green leafy vegetables, potatoes,
  broccoli
• Heat and oxygen sensitive

64
Vitamin C

• Deficiency ? Scurvy
• Poor wound healing - Increased infection
• Weakness
• Bleeding gums
• Loose teeth
• Broken blood vessels
• Loss of appetite
• Joint pain and fragile bones
• Anemia

65
Vitamin C

• Populations at increased risk
• Alcoholics
• Elderly
• Babies and toddlers fed only milk/cereals
• Smokers
• After illness or stress
• Fever and stress deplete vitamin C stores

66
Vitamin C

• Toxicity Symptoms
• Diarrhea
• Cramps, nausea
• Headaches, insomnia
• May interfere with lab tests and meds
• Increased risk kidney stones
• Over-absorption of iron

67
Fat Soluble Vitamins

• A
• D
• E
• K

68
Vitamin A

• Chemical nature
• Active forms of vitamin A
• Retinol
• Retinoic acid
• Retinal
• Precursor form
• Beta-carotene
• Converted to active vitamin A as needed

69
Vitamin A

• Functions
• Need for night vision
• See handout
• Need for protein synthesis
• Plays a role in cell differentiation
• Need to build healthy epithelial and mucous
  tissue
• Need to maintain healthy cornea

70
Vitamin A

• Functions
• Plays a role in reproductive health
• Sperm production
• Fetal development
• Sexual maturation
• Need for bone growth

71
Beta-Carotene

• Functions beta-carotene
• Can be converted to active vitamin A as needed
• Antioxidant

72
Vitamin A

• Recommended intake
• 700-900 RAE micrograms/day
• RAE retinol activity equivalents
• Older unit is IU International Units
• See page 360 for conversions between these units
• UL 3000 RAE
• UL refers to active vitamin A only, not
  beta-carotene

73
Vitamin A

• Food Sources Vitamin A
• All animal sources
• In fatty portion of the food
• Dairy products
• Eggs
• Meat, liver
• Fortified skim milk and margarine

74
Beta-Carotene

• Food Sources
• All plant sources
• Yellow/orange/red fruits and vegetables
• Carrots, apricots, cantaloupe, mangos, pumpkin,
  sweet potato, winter squash, peppers
• Dark green leafy vegetables
• Spinach, kale, broccoli, beet greens (but not the
  beet!)

75
Vitamin A

• Deficiency
• Night blindness
• Blindness
• Leading cause of blindness worldwide
• ½ million children go blind each year due to a
  vitamin A deficiency

76
Vitamin A

• Deficiency
• Keratinization ? dry, cracked skin
• Reduced secretions
• GI tract
• Bladder
• Lungs
• Above symptoms increase risk of infection

77
Vitamin A

• Deficiency
• Anemia
• Slow bone growth
• Painful joints
• Cracked, cracked teeth
• Delayed sexual maturity
• For others see pages 374

78
Vitamin A

• Toxicity
• Teratogenic
• monster producing
• GI distress, weight loss
• Bone issues
• Joint pain
• Stunted bone growth and more

79
Vitamin A

• Toxicity
• Headaches, pressure inside skull
• Blurred vision
• Fatigue, muscle weakness
• Skin rashes
• Dry, cracked, bleeding lips
• Dry, brittle hair

80
Vitamin A

• Vitamin A toxicity can be fatal
• Polar bear liver story
• Symptoms go away quickly if diet changes
• Toxicity is never from beta-carotene sources
• Beta-carotene toxicity..

81
Vitamin D

• Chemical nature
• Vitamin D is a sterol
• Body can make from cholesterol
• Requires sunlight exposure
• Synthesis of vitamin D
• See page 376

82
Vitamin D

• Functions
• Bone mineralization
• Works with other nutrients
• Vitamins A, C. K
• Several minerals

83
Vitamin D

• Functions
• Regulates calcium and phosphorus levels
• Stimulates Ca and P absorption in SI
• Regulates movement of Ca and P in/out of bones
• Stimulates kidneys to retain Ca and P
• All of the above are related to bone
  mineralization

84
Vitamin D

• Other Functions
• Acts as a hormone
• Not fully understood
• Many target organs
• Brain and CNS
• Muscle
• Reproductive cells

85
Vitamin D

• Recommended intake
• Depends upon sun exposure and skin color
• 5-10 micrograms/day (AI)
• UL 50 mcg/day

86
Vitamin D

• Food sources
• Fortified milk and margarine
• Butter
• Egg yolks
• Liver
• Fatty fish and fish oils
• animal sources

87
Vitamin D

• Deficiency
• Bone abnormalities
• Kids ? rickets
• Adults ? osteomalcia

88
Vitamin D

• Populations at risk for deficiency
• Inner-city kids
• Dark skinned
• Live in a northern climate
• Limited sun exposure
• Elderly
• Kidney or liver disease
• Vegans

89
Vitamin D

• Toxicity
• Very toxic
• Can be lethal
• Milk story
• Toxicity is never from sun exposure

90
Vitamin D Toxicity

• Symptoms
• Calcium deposits in soft tissue
• Muscles, lungs, heart
• Kidney stones
• Calcium deposits on walls of arteries
• Joint pain
• Frequent urination
• GI distress

91
Vitamin E

• Chemical nature
• A type of tocopherol
• 4 forms
• Alpha, beta, gamma, delta
• Alpha-tocopherol is the most active form
• Other forms have very limited bioactivity

92
Vitamin E

• Functions
• Antioxidant
• Component of animal cell membranes
• Protects unsaturated fatty acids in cell
  membranes
• Other roles are not clearly defined, but likely
  exist

93
Vitamin E

• Recommended intake
• 15 mg/day
• Need more if eat more polyunsaturated fats
• most students did not meet their vitamin E
  requirement on the day analyzed

94
Vitamin E

• Food sources
• Vegetable oils
• Nuts and seeds
• Whole grains
• Green leafy vegetables
• Liver
• Wheat germ
• Egg yolks easily destroyed by heat and oxygen

95
Vitamin E

• Deficiency
• Rare as most vitamin E is recycled
• See in premature babies
• Transferred from mom to baby in last weeks of
  pregnancy
• Cystic fibrosis patients
• Due to poor fat absorption

96
Vitamin E

• Symptoms deficiency
• Hemolytic anemia
• RBC break open
• Neurological problems with prolonged deficiency
• Loss of coordination
• Vision and speech problems
• Does not prevent/cure MD

97
Vitamin E

• Vitamin E may help with
• Leg cramps
• Intermittent claudication
• Fibrocystic breasts disease
• lumpy breasts

98
Vitamin E

• Toxicity Rare
• Supplements recommended by many, but not above
  the UL 1000 mg
• 200 mg supplement probably enough
• May interfere with blood clotting
• Stop taking supplements prior to surgery
• Other symptoms nausea, fatigue, blurred vision

99
VITAMIN K

• Functions
• Need for synthesis of blood clotting proteins
• Plays a role in regulation of calcium levels

100
Vitamin K

• Recommended intake
• 90-120 mcg/day
• Sources
• Made by GI tract bacteria
• Dark green leafy vegetables, cabbage family
• Liver
• Milk

101
Vitamin K

• Deficiency rare
• Symptoms
• Bleeding, hemorrhaging
• Bone weakness
• Populations at risk
• Babies
• After long-term antibiotic treatment
• CF

102
Vitamin K

• Toxicity rare
• Occurs with supplement overuse
• Take with caution, even if prescribed
• Symptoms
• RBC break open
• Jaundice
• Brain damage
• Interferes with anti-clotting meds