The Vitamins
David L. Gee, PhD
Professor of Food Science and Nutrition
Central Washington University
FCSN 245 - Basic Nutrition
Dietary Supplement Use
(USA)
$ 4,300,000,000 for vit/min in 1995
$ 1,400,000,000 for herbs
35-40% adults regular users
females > males
66% multi-vit/min
37% vitamin C
19% vitamin E
Calcium supplements
Dietary Supplement Use:
Pros
Supplements dietary deficiencies
calcium
folic acid
Amounts used in some studies not
attainable with dietary sources
antioxidants
Relatively low cost
Dietary Supplement Use:
Cons
False sense of security
folic acid and pregnancy
Does not contain all potentially useful chemicals
in foods
Example: compounds found in plants that may be
health promoting (phytochemicals)
Toxicity almost only due to supplement use
Costs significant
low income
Heavy users of supplements (athletes)
Certain supplements are expensive
Chondroitin sulfate – bone/cartilage: $30-50/mo
SAMe – depression: $40-50/mo
Exam 3 – Tuesday, March 6
 Proteins and Amino Acids (chap 6)
 EAA, RDA, functions, athletes
 Genetically modified foods (p 472-480)
 Vegetarian diets
 Protein quality
 Protein deficiency (kwashiorkor/marasmus)
 Energy and Weight Loss (chap 9)
 Energy, TEE, BMR, factors affecting BMR, activity, TEF
 Calorimeters (bomb, direct, indirect)
 Weight loss, obesity risks, QOL, prevalence, high risk groups
 Healthy weight, assessment
Calculate BMI, know cutpoints for blood pressure, sugar, lipids
 Dietary approaches (Balanced, Lo-Carb, restrained CHO, non-diet
 Exercise
 Drugs/Surgery
Vitamin & Mineral Deficiency:
A Global Progress Report
UNICEF, 2004
80 developing countries studied
Accounts for 80% of world population
1/3rd of world population do not reach
their physical and intellectual potential
because of vitamin/mineral deficiency
Vitamin & Mineral Deficiency:
A Global Progress Report
UNICEF, 2004
Vitamin A deficiency
40% of children <5yrs with mild to severe
deficiency
Compromised immune deficiency
blindness
stunted growth
Contributes to 1 million deaths of young
children/yr
A Solution: supplementation with betacarotene, 2x/yr, fortification of foods
Vitamin & Mineral Deficiency:
A Global Progress Report
UNICEF, 2004
Iodine deficiency
Goiter: enlarged thyroid gland, lethargy
Cretinism: severe mental and physical
retardation in infants of deficient mothers
Reduces IQ by 10-15 points
80% of developing countries have goiter rates of
> 10%
A Solution: iodized salt (use declined from
75% to 65% in last decade!)
Woman with iodine deficiency resulting
In a goiter.
Myxedematous endemic cretinism in the Democratic Republic of Congo : Four
inhabitants aged 15-20 years : a normal male and three females with
severe longstanding hypothyroidism with dwarfism, retarded sexual
development, puffy features, dry skin and hair and severe mental retardation.
Vitamin & Mineral Deficiency:
A Global Progress Report
UNICEF, 2004
Iron deficiency
Anemia: fatigue, apathy in adults, poor
academic performance in children (7-10pt drop
in IQ)
~45% of children between 6mo-2 yrs
20 countries over 70%
A solution
Supplementation (bad taste, constipation)
Fortification
• Salt with iodine and iron
• Vitamin/mineral mixes added to foods
• Fortified foods
The Discovery of
Vitamins
The Germ
Theory of
Disease
Scurvy: Disease of
sailors
Beri-Beri: Disease
of poor Asians
The Discovery of Vitamins
The Germ Theory
of Disease
Rickets: Disease of
poor Northern
European children
Pellagra: Disease of
poor corn eating
cultures
The Discovery of
Vitamins
The Vitamin Theory of Disease
Scurvy: Disease of sailors
Vitamin C deficiency
Beri-Beri: Disease of poor Asians
Thiamin deficiency
Rickets: Disease of poor Northern European
children
Vitamin D deficiency
Pellagra: Disease of poor corn eating cultures
Niacin deficiency
Vitamins: Definition
Organic compound found in foods
Required in small amounts
Required in the diet (dietary
essential)
Proven to be required for health,
growth, and reproduction
deficiency syndrome identified
Vitamin
Nomenclature
Fat soluble “A” & Water soluble “B”
“Vital amines”
 vitamines = vitamins
Vitamin B “complex”
collection of water soluble vitamins that function as
enzyme co-factors
Vitamin C
Vitamins D and E
Mistaken Vitamins
Fat and Water Soluble
Vitamins
Fat Soluble Vitamins (A, D, E, K)
Soluble in lipids and solvents
Excess stored and not excreted
Excess may be toxic
Deficiency slow to develop
Fat and Water Soluble
Vitamins
Water Soluble Vitamins
B vitamins, C
Soluble in water
excess excreted in urine, little
stored
generally less toxic
deficiency develops quickly
General Functions of
Vitamins
Hormones
Vitamin D
calcium homeostasis
Vitamin A
cell division and development
General Functions of
Vitamins
Non-specific chemical
reactions
Vitamin E
antioxidant
Vitamin C
chemical reducing agent
General Functions of
Vitamins
Coenzymes or Cofactors
chemicals that assist enzymes to
function as catalysts
B vitamins
Vitamin C, A, K
Vitamin A: types and
sources
Retinoids
retinol, retinal, retinoic acid
animal foods, milk fortification
Carotenoids
beta-carotene
plants
vitamin A precurser
Vitamin A: functions
Visual pigment: rhodopsin
“night blindness”
Maintenance of epithelial cells
regulation of keratin protein synthesis
Xeropthlamia
intestinal malabsorption
Bone and Immune System
Development
Vitamin A: Deficiency
Common in developing countries
3 million children with severe
deficiency
blindness, poor growth and appetite
275 million children with mild
deficiency
impaired immunity
Vitamin A: Toxicity
10 times RDA chronically
100 times RDA acute dose
hair loss, joint pain, birth defects
carotenoids are non-toxic
toxicity due to vitamin supplement
overdose
Vitamin D: Types and
Sources
Dietary sources: animal foods,
fortified milk
Human Synthesis of Vitamin D
Skin: cholesterol + sunlight
“Sunshine Vitamin” – UV-B rays
Vitamin D3
5-10 minutes, arms and legs, mid-day sun
Liver & Kidney for activation
1,25-di-OH-D3
Final Exam – Winter 2007
Tuesday, March 15, noon
25% vitamins and minerals
Lecture materials
General info on vitamins/minerals
Developing world vitamin/mineral deficiencies
Required reading
Chapter 7 (vitamin C ; vitamin A/carotenoids )
Chapter 8 (nutrients involved in bone health)
Chapter (iron ; folate & B-12 )
Final Exam – Winter 2006
75% comprehensive
“questions that you should know the
answers to one or two years from now.”
Study class notes
Review old exams
Vitamin D: Functions
Helps regulate blood calcium
levels
When blood calcium levels are
low, vitamin D (and other
hormones):
Increases dietary calcium absorption
Decreases urinary calcium excretion
Increases bone calcium mobilization
Vitamin D: Deficiency
Rickets
bone deformities in children
Osteomalacia
weak bones due to low calcium
content
Vitamin D deficiency
Calcium deficiency
multiple pregnancies
Vitamin D: Toxicity
5 times the RDA chronically
calcification of soft tissue
toxicity due to excessive
vitamin supplementation
Calcium
Functions
Bone Structure (99%)
Regulator of Metabolism (1%)
nerve impulse transmission
muscle contraction
blood clotting
etc.
Calcium
Regulation of Blood Calcium
10 mg/dl of blood
hypocalcemia & hypercalcemia
abnormal muscle cramping
nerve irritation
Controlled by:
vitamin D, parathyroid hormone, calcitonin
Calcium RDA
1998 RDA’s (AI)
1300 mg/d : children & teens
1000 mg/d : adults
1200 mg/d : older Americans
Usual intakes are low
Osteoporosis
Brittle, weak bones due to loss of total
bone mass (minerals and protein)
Prevalence
11% of > 65 yrs
22% of > 65 yrs in 20 yrs
24 million fractures/yr
200,000 hip fractures, 1/6 fatal
3D Visualization of data obtained by
x-ray microtomography of the bone
structure of the vertebrae of a 50 year
old (left) and a 70 year old (right)
This graph shows rates in the USA in 1984-87, adapted
from Jacobsen, SJ in American J Public Health 80:872, 1990.
An illustration of the consequence of osteoporosis on
the spinal column.
Elderly woman with dowagers hump, a marked
abnormal curving of the spine caused by osteoporosis
Other osteoporosis fact:
National Osteoporosis Foundation - 2003
10 million with osteoporosis
18 million with low bone density
1 in 2 women will develop
osteoporosis sometime in their life
(1 in 8 men)
Osteoporosis
Risk Factors
Genetics
Family History
Ethnicity
Caucasian > Asian > Blacks
Osteoporosis
Risk Factors
Gender
associated with declines in
estrogen production
post-menopause
anorexia, female athletes
Undertreatment of Osteoporosis
in Men with Hip Fracture.
Arch. Int. Med. (Oct. 2002)
10 million Americans with osteoporosis
2 million are men
Of 110 men hospitalized with hip fracture
4.5% received treatment for osteoporosis
1 year mortality was 32%
Average age 80 yrs
Of 253 women hospitalized with hip fracture
27% received treatment for osteoporosis
1 year mortality was 17%
Average age 81 yrs
Osteoporosis
Risk Factors
Chronic Calcium Deficiency
Lack of Exercise
Prevention of
Osteoporosis
Exercise
Dietary Calcium
“Rule of 300”
300 mg/d from plant sources
300 mg/d from each serving of
dairy
Prevention of
Osteoporosis
Other factors that may
increase calcium loss
high caffeine intake
high protein intake
high alcohol intake
cigarette smoking
Prevention of
Osteoporosis
Calcium Supplements
Calcium carbonate
least expensive
Tums
poor absorption
Calcium citrate/malate (CCM)
expensive, well absorbed
Prevention of
Osteoporosis
Adequate amounts of vitamin D
avoid excesses
Hormonal replacement in high
risk women
http://www.mhhe.com/biosci/ap/mediacentral/nutrition_animations/osteoporosis_final.swf
Folic Acid
DRI (RDA): 1998
400 ug/d (180-200 old RDA)
600 ug/d pregnancy (400)
Typical folate intake: 200 ug/d
Dietary Sources
foliage: fruits & vegetables
Folic Acid
Functions
“single carbon metabolism”
DNA synthesis (cell division)
other reactions
Folic Acid
Deficiency
Megaloblastic Anemia
large abnormal red blood cells
Elevated blood homocysteine
CHD risk factor
Folic Acid
Deficiency
Neural Tube Defects
spina bifida - lower body
paralysis
required early in pregnancy
Grain fortification (1998)
will add 100-200 ug/d to diet
Vitamin B-12
Cobalamine
contains cobalt
DRI (1998) : 2.4 ug/d (old 2 ug/d)
Dietary sources:
animal foods
fortified cereals
Vitamin B-12
Functions
“single carbon isomerization”
synthesis of DNA (folate
interaction)
nerve fiber sheath synthesis
Vitamin B-12
Deficiency
Pernicious Anemia
megaloblastic anemia
nerve injury
peripheral weakness and numbness
progressive degeneration to death
concern among the elderly
Vitamin B-12
Digestion and Absorption
Requires functioning stomach
“intrinsic factor protein”
acid production
B-12 and Folic Acid
Excessive folic acid can mask nerve
degeneration of pernicious anemia
FDA regulates dosage of folate
supplements
FDA limited amount of folate
fortification in grains
Nutritional
Antioxidants
Oxidative Tissue Injury
Oxygen free radicals
unpaired electrons
superoxide O2-.
hydroxy free radical OH.
hydrogen peroxide
Oxidative Tissue Injury
Causes chain reactive damage
to:
Cell membranes (hi PUFA)
Proteins
DNA
Oxidative Tissue Injury
Associated with:
Coronary Heart Disease
oxidized LDL-cholesterol
Carcinogenesis
Chemical Toxicity
Auto-immune dieseases
Aging
Sources of Oxygen Free
Radicals
Normal energy metabolism
nutrient + O2 --> CO2 + H2O + energy
Electron transport system
O2 --> H2O + energy
but: O2 --> O2-. --> H2O + energy
Sources of Oxygen Free
Radicals
D-amino acid metabolism
D-AA --> C-skeleton + ammonia +
H2O2
Metabolism of foreign chemicals
drugs, pesticides, toxins, etc...
Ozone, nitrogen oxides, UV light,
smoke, radiation, etc...
Cellular
Antioxidants
Antioxidant Enzymes
Catalase (iron)
removes hydrogen peroxides
Superoxide Dismutase (Cu, Zn)
removes superoxide radicals
Cellular
Antioxidants
Antioxidant Enzymes
Glutathione Peroxidase (Se)
removes peroxides
Mineral supplements are
ineffective and may be toxic
Cellular
Antioxidants
Nutritional Antioxidants
Vitamin E
Carotenoids and other plant
phytochemicals
Vitamin C
Vitamin E
Tocopherols
Dietary sources:
widespread, highest in plant oils
Deficiency:
rare in adults
premature infants: hemolytic anemia
Vitamin E
Function:
free radical scavenger in
membranes
RDA: 8-10 mg/d
“Research dosages”: 400-800 mg/d
Toxicity: rare, may be non-toxic
below 1000 mg/d
Plant
Phytochemicals
Beta-carotene & carotenoids
Plant polyphenols
garlic
green tea
grape skins
cruciferous vegetables
Antioxidants with “specific niches”
Vitamin C
Ascorbic Acid
Food Sources
fruits
vegetables
Deficiency: Scurvy
poor wound healing
impaired immune system
Vitamin C
Functions
Antioxidant
water soluble free radical scavenger
Collagen synthesis
connective tissue protein
Synthesis of neurotransmitters,
thyroxine, etc.
Aids in absorption of dietary iron
Vitamin C
RDA : 60 mg/d
RDA (smokers): 100 mg/d
typical intake 100 mg/d
“Effective research dosages” :
100-500 mg/d
Vitamin C
“Toxicity” > 1000 mg/d
diarrhea
kidney stones
promotes “iron overload” toxicity
Interfers with important lab tests
blood in stools (colon cancer)
urinary and blood glucose (diabetes)
Iron
Functions:
Hemoglobin
Myoglobin
Iron enzymes
catalase
electron transport system
Iron Deficiency
Iron deficiency anemia
fewer, smaller, paler red blood cells
fatigue
5-10% of US premenopausal women
up to 40% of population in
developing countries
Iron Deficiency
Causes
Blood loss
menstrual blood loss
parasites and bleeding ulcerations
Inadequate dietary intake
RDA men = 10 mg/d
RDA women = 15 mg/d
US usual intake 6 mg/1000 Cal
Dietary Sources of
Iron
Heme Iron
meats (Hb & Mb)
20-30% absorbed
Non-heme Iron
plants
inorganic iron
1-10% absorbed
vitamin C increases absorption
iron cookware
Iron Overload
Toxicity
Children (accidental poisoning)
Men and post-menopausal women
Genetic “defect”
improved iron absorption
Excess iron is a pro-oxidant.
oxidized LDL-C
tissue injury
Iron Overload
Toxicity
May occur in 10% of men
Treatment
avoid iron containing
supplements
avoid excess vitamin C
supplements
bleeding or blood donation