Download lecture 10

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?
 They are: 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,
 Free radical oxygen is considered
(ROS).
Cell damage
 Free radicals can damage cells
 May take an electron from stable molecules

is a significant sight
 LDL, DNA, cell proteins also damaged
 Negative effects

Antioxidants stabilize free radicals
 Vitamins
 Co-
stabilize by donating electrons & hydrogen
 Minerals
 Coconvert free radicals for excretion
 Antioxidant Systems

Example: Glutathione Peroxidase
 removes H2O2 & stops free radical damage
 Phytochemicals
Vitamin E
Functions
 Antioxidant stops ROS production from fat oxidation
 Protects PUFA’s & LDL
 Enhances immune function, cell signaling, gene
expression
 Improves Vitamin A absorption
 Prevents hemolytic anemia
Deficiency
Toxicity
 When?
 Very low birth weight infants
 UL - 1,000 mg per day


Develop disorder of fat
metabolism
 Increased risk of
bleeding/hemorrhage
 What?
 Neurological Disorders
 Genetic spinal disease
 Myopathy
 Retinopathy
 Muscle fiber dysfunction
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



Protects LDL, lungs, white blood cells, stomach cells
Regenerates vitamin E radicals
Synthesizes
.
 RDA

Who needs more?
 Best sources:
 Deficiency – _____________
 Collagen is too unstable to function
 Brown spots on the skin, spongy gums & bleeding
from mucous membranes
 Symptoms reversed by additional 10 mg/day
 Toxicity
 Excess excreted in the urine;
 UL


risk of toxicity.
Kidney stone formation
Indigestion, especially on an empty stomach
 Diarrhea, nausea, vomiting, flushing, headache, fatigue
Pro-vitamin A
Carotenoids
Fat-soluble plant
pigments that the
body stores in
liver & adipose
Antioxidant & Immune-Enhancing Activity
•Anti-carcinogenic and anti-aging
•Protects lipid cells/cell membranes
Prevents Vitamin A Deficiency
•Beta-carotene converts into
active vitamin A.
Promotes Proper Cell Communication
Essential for normal growth and development,
immune system function, and vision; decreases
risks of certain cancers
•No specific deficiency symptoms
•Excessive Intake:
•Reversible and harmless
•No RDA for pro-vitamins
•Found in red, orange, yellow & deep green produce
:
Vitamin A
 Active form is
 Produced by β-carotene
 Attached to Fatty Acids in foods, transported in
chylomicrons
 Stored in liver
.
 Measured in RAE, RE, IU
 Only found in animal products
Functions
 Antioxidant
 Scavenge free radicals to protect LDL from oxidation
 Vision
 Forms proteins in the retina of the eye
 Cell differentiation
 Critical for cells to mature and perform specific function
 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
 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 body
 Needed for production of a thyroid hormone
 Aids in immune function
 Best known for role in glutathione peroxidase (GSH)
system, an antioxidant defense
 Reduces hydrogen peroxide & stops free radical production.
 Lowers production of inflammatory markers
Selenium Intake
 Only needed in little amounts to maintain health
 Found in wheat, organ meat, seafood, food 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
 Higher rates of some forms of cancer
Cancer
 Diseases characterized by “out of control” cell growth
 Aggressive invasion of tissues & organs
 Tumors
 Mass of undifferentiated cells with no function
 Benign or malignant
 3 Stages of development
 Initiation
 Propagation
 Progression
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 cancer in the US:
 Immature cell DNA damage = uncontrolled growth
 Risk doubles after 5+ sunburns
 Tanning before 35 ↑ risk of most invasive by
%
 Nonmelanoma & melanoma
 5)
 Sedentary life increases risk of colon & other cancers
 Moderate-vigorous exercise =
Antioxidants can prevent cancer
 Enhance the immune system
 Destroy & remove precancerous cells
 Inhibit cancer and tumor cell growth
 Prevent oxidative damage to DNA
 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
 Overall these antioxidant blends are best
Cardiovascular Disease
 All diseases of the heart & blood vessels
 Major risk factors:
 Also low HDL, diabetes, family history
 Newly identified risk factor

 Weakens blood vessel plaque
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
Phytochemicals
 Naturally occurring plant chemicals
 Not considered nutrients… yet
 Have antioxidant properties
 Recognize the general role of phytochemicals
 Identify functional foods and their respective nutrient
 Understand the role of pro-biotics
Objectives
 Reduce inflammation
A
, Alzheimer’s, cardiovascular disease
 Enhance enzyme activity
 Protect against cancer
 Protect against infections
 Antibacterial agents
 Reduce cardiovascular disease
Functions
 Interact with each other in the body
 Phytochemicals interact with macronutrients and
micronutrients
 Phytochemicals act in different ways under different
circumstances in the body
 Protective in low doses commonly provided by foods
 Supplements?
New Knowledge
 Provide health benefits beyond basic nutrition
 Include fortified & enriched foods and dietary
supplements
 May contain
 Natural phytochemicals or helpful bacteria
 FDA regulated?
 “Functional” ingredient added to a food must be
generally recognized as safe
Functional Foods
 Iodine
 Omega-3
 B-vitamins
 Vitamin D
 Plant Sterols
Examples of functional foods
 Eggs
 Chickens are fed diets high in:
 Extra Dark Chocolate
 High
content

Maybe higher than tea, wine, veggies
 Plant Sterols
 Reduce cholesterol levels
 Added to: buttery spreads, yogurt, breads, etc.
Hot on the market
 Live organisms found in (or added to) fermented dairy
products
 Our balance of beneficial bacteria can be harmed by:
 Bacteria attach to intestinal wall
 Aid in removing bad bacteria, virus’s, fungi
 Produce nutrients
 Benefit immune function
Probiotics
 Diarrhea from antibiotics/infections
 Infections in children
 IBS and IBD
 H. pylori
 UTI
 Eczema
 Lactose intolerance
 Risk of allergies in infants
Pro-biotics may improve…