Download RDAs for vitamin E

HLTH 120N Lecture 10
Objectives
 Understand the process of oxidation & production of





free radicals
Recognize the major antioxidant vitamins & minerals
and their role in preventing cancer, heart disease, and
age related eye disorders
Explain the glutathione peroxidase antioxidant system
Understand the 3 stages in the development of cancer
Identify the difference between modifiable and unmodifiable risk factors for disease
Know the newest known risk factor for heart disease
Why do we need antioxidants?
 Compounds that protect cells from damage caused by
oxidation
 Oxidation
 Atoms
electrons
 Usually an even exchange or 2 unstable electrons pair
 Highly unstable Free Radicals form if they do not pair
 Free radicals form with
 ATP production, immune reactions, radiation, environmental toxins,
 Free radical oxygen is considered
(ROS).
Cell damage
 Free radicals can damage cells
 May take an electron from stable molecules
one of most significant sights


Nutrient & fluid transport no longer regulated
 LDL, DNA, cell proteins also damaged
 Negative effects

, heart disease, diabetes, Alzheimer’s,
Parkinson’s, etc.
Antioxidants stabilize free radicals
 Vitamins
 Stabilize by donating electrons & hydrogen
 Minerals
 Co
in antioxidant systems, convert free radicals
to compounds we can excrete
 Systems


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Superoxide Dismutase: convert to other substances
Catalase: removes H2O2 from body
Glutathione Peroxidase:
removes H2O2 & stops free radical damage
 Phytochemicals
Vitamin E
 Functions as
.
 Antioxidant, stops ROS production when fat is oxidized.
 Protects PUFA’s & LDL
 Enhances immune function, cell signaling, gene expression
 Improves absorption of Vitamin A
 Prevents hemolytic anemia
 Food Sources
 Fortified cereals, seeds, nuts (almonds) , vegetable oils
 Green leafy vegetables, sweet potatoes, broccoli
Deficiency
 When?
 Fat metabolism disorders
 Very low birth weight infants
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
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Develop disorder of fat metabolism
What?
Neurological Disorders
Genetic spinal disease
Myopathy

muscle fibers do not function, resulting in weakness
 Retinopathy
Toxicity
 May increase risk of bleeding/hemorrhage

muscle fibers do not function, resulting in weakness
 UL - 1,000 mg per day
Food sources and amount of Vitamin E
Wheat Germ Oil 1 tbs
20 mg
Fruit of 1 Avocado
12 mg
Tomatoes
11 mg
Sunflower Seeds, ¼ cup
8.3 mg
Hazelnuts, 1oz
4.3 mg
Peanut Butter, 2tbs
2.9 mg
Canned Blue Crab, 1 cup
2.5 mg
Mango, 1 fruit
2.3 mg
Peanuts, Dry Roasted, 1oz
2.2 mg
Olive Oil, 1tbsp
1.9 mg
Almonds, 1 oz=
7.4 mg
Spinach, 1 cup cooked
6.7 mg
Vitamin C
 Metabolic Functions
 Antioxidant
 Protects LDL, lungs, white blood cells, stomach cells
 Regenerates vitamin E; gains electrons from GSH
 Synthesizes
.
 RDA
 Found in many food sources naturally
 Possible for most people that eat a balanced diet to meet to
RDA
 Smokers have 35 mg higher recommendation
 Who else needs more?
• Food Sources

Fruits and vegetables are the best source

Fruits and vegetables that are high in vitamin C

, potatoes, strawberries, tomatoes,
kiwi, broccoli, spinach, and other leafy greens,
cabbage, green and red peppers, and cauliflower

•
destroy vitamin C
Steam & Stir-fry to compromise the least
 Deficiency – _____________
 Collagen is too unstable to function
 Brown spots on the skin, spongy gums & bleeding
from all mucous membranes
 Symptoms could be completely reversed by additional
supplementation of only 10 mg/day
 Toxicity
 Excess excreted in the urine;
 UL is 2000 mg/day


risk of toxicity.
Increased formation of kidney stones
Indigestion, especially on an empty stomach
 Diarrhea, nausea, vomiting, flushing, headache, fatigue
Pro-vitamin A
Inactive form,
the body must
convert it
Carotenoids
Fat-soluble plant
pigments that the
body stores in
liver & adipose
Antioxidant & Immune-Enhancing Activity
•Anti-carcinogenic and anti-aging
•Especially protects lipid cells/cell membranes
Prevents Vitamin A Deficiency
•Beta-carotene converts into retinol, active vitamin A.
Promotes Proper Cell Communication
•Ability to stimulate cell to cell communication
Essential for normal growth and development,
immune system function, and vision; decreases
risks of certain cancers
•No specific deficiency symptoms
•Can cause symptoms associated Vitamin A deficiency.
•Excessive Intake:
•Reversible and harmless
•No RDA for pro-vitamins
•Found in red, orange, yellow & deep green produce
:
Vitamin A
 3 forms in the body
 Retinol is produced by β-carotene
 Attached to Fatty Acids in foods, transported in
chylomicrons
 90% stored in liver
 Measured in RAE, RE, IU
 Only found in animal products
 Liver, eggs, whole-fat and reduced-fat dairy
Functions
 Antioxidant
 Scavenge free radicals to protect LDL from oxidation

Decreases heart disease & cancer
 Vision
 Forms proteins in the retina of the eye

Essential to reactions to brightness and color vision
 Cell differentiation
 Critical for cells to mature and perform specific function
 Organ development & immune cells
 Reproduction & bone growth
Toxicity
Deficiency
 At 3-4x the RDA usually
due to
.
 Birth defects &
miscarriage, fatigue,
blurred vision, hair loss,
bone pain, liver &
nervous system damage
 Acne treatment with
vitamin A derivative
 __________________
 A serious concern in pre-
school aged children
 250,000-500,000 suffer
permanent blindness each
year
 Night & color blindness
 Poor growth & cell
function
 Hyperkeratosis
 Excess keratin buildup
Selenium
 Found in varying amounts in soil
 Contained in 2 amino acids in our bodies (stored & active)
 Needed for production of thyroxine hormone
 Aids in immune function
 Best known for role in glutathione peroxidase (GSH)
system, one our major antioxidant defense systems
 Reduces hydrogen peroxide & stops free radical production.
 Lowers production of inflammatory markers
Selenium Intake
 Only needed in little amounts to maintain health
 Sources
 wheat, organ meats, seafood, foods grown in soil
Too much?
-brittle hair/nails
-skin rashes
-nausea
-vomiting
-weakness
-cirrhosis of liver
Not enough?
-impaired immunity
-infertility
-depression
-impaired cognition
-muscle pain and wasting
Related Deficiency Disorders
 Kashin-beck disease: cartilage disorder
-results in deforming arthritis
 Keshan disease: heart disorder caused by deficiency
-found in children in China
-soil depleted of selenium
-prevention= supplementation
 Higher rates of some forms of cancer
Other antioxidant minerals
 Superoxide dismutase system
 Copper, Zinc, Manganese
 Catalase System
 Iron
Cancer
 Group of diseases characterized by cell growth that is
“out of control”
 Aggressive invasion of tissues & organs
 Tumors
 Mass of undifferentiated cells with no function
 Benign or malignant
 3 Stages of development
 Initiation
mutation of cells
 Propagation
cells divide
 Progression
spreads to other sites
5 Modifiable Risk Factors
 1)
 40+ carcinogenic compounds
 2)
 Alcohol, fat, cured meat
 Phytochemicals, vitamins, minerals
 3)Infectious Agents
 Bacterial infections (H.Pylori)
 4)
 Most common form of cancer in US is
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.
Damage DNA of immature cells, which are then
uncontrollable
Risk doubles after 5+ sunburns
Tanning before 35 ↑ risk of most invasive by
%
Nonmelanoma & melanoma
 5)Physical Inactivity
 Sedentary life increases risk of colon & other cancers
 Moderate-vigorous exercise = 20-30% ↓ risk
Antioxidants can prevent cancer
 Enhance the immune system
 Destroy & remove precancerous cells
 Inhibit cancer and tumor cell growth
 Prevent oxidative damage to DNA
 Scavenge free radicals to stop chain reactions
 Eating whole foods (fruits, grains, vegetables) ↓ risk
Antioxidant Supplements & Risk
 Research is controversial: association is unclear
 Vitamin E supplements may reduce risk for prostate,
colon, and rectal cancer & may increase for stomach
 β-carotene may increase lung & prostate cancer in
smokers
 Selenium found to reduce prostate, colon, lung
 Supplementing with β-carotene, E, and selenium
reduces cancer mortality
Cardiovascular Disease
 Encompasses all disease of the heart & blood vessels
 5 Major risk factors:
 Also low HDL, diabetes, family history
 Newly identified risk factor

 Weakens blood vessel plaque

More likely to burst causing heart attack & stroke
Inflammatory Markers
 C-Reactive Protein levels indicate inflammation
 w/ high cholesterol, ↑ heart attack by 9x
 Vitamin E & lycopene
 Reduce vessel damage & inflammation
 Vitamin E supplements may reduce death by heart
disease in smokers
Age-related vision impairment

 Leading cause of blindness in 55+
 Macula is central part of retina
 No known cure for reduction in site

 Damaged lens causes cloudiness
 Surgery can treat light insensitivity
 Antioxidant cocktail of Vitamin C & E, zinc & β-carotene
can reduce progression