Antioxidants

                                                                                   

Oxidation Chemical rx in which atoms

lose electrons May result in free radical

formation

Structure of Atoms Atom: the smallest unit of matter.

Atoms are composed of Nucleus – positively charged center portion

of the atom Electrons – negatively charged particles

surrounding the nucleus

Oxidation Molecules are composed of atoms.

During metabolic reactions, electrons can be transferred From the atoms of one molecule To the atoms of another molecule

Oxidation

Oxidation Oxidation: the loss of electrons from a

molecule.

Reduction: the gain of electrons by a molecule.

Oxidation and reduction usually occur together as an exchange reaction.

OxidationStable atoms contain an even number of paired electrons.

Free radical: an atom that has lost an electron and is left with an unpaired electron.

Free radicals are highly reactive and can cause damage to molecules in the cell.

Free Radicals and Diseases

Antioxidants Substances that are able to neutralize

reactive molecules and reduce oxidative damage

Result of metabolic processes and environmental sources

Vitamin C, Vitamin E, beta-carotene, Vitamin A, selenium, iron, zinc, copper and manganese

Vitamin E Functions: Anti-oxidant

Guards against damage to membranes from oxidizing compounds

Deficiency: Rare (premature infants under 3.5 pounds, people unable to absorb fat or metabolize fat properly Suppresses the immune system because

vitamin E protects White Blood Cells

Vitamin E Toxicity: Rare Sources: Vegetable oils, nuts and

green leafy vegetables, fortified cereals

There's sweet news about hot cocoa Hot cocoa tops red wine and tea in antioxidants;

may be healthier choice More antioxidants per cup than a similar serving of red

wine or tea per serving basis, the antioxidant concentration in

cocoa was the highest: It was almost 2 times stronger than red wine, 2-3 times stronger than green tea, and 4-5 times stronger than that of black tea

New research underlines antioxidant activity in chocolate

Vitamin E tocotrienol shows brain protection promise

Vitamin C Functions Collagen Formation antioxidant

reduce cancer risk helps absorb iron from food Reduces risk of colds?????

probably not Linus Pauling’s study NutraIngredients

Vitamin C Deficiency: called scurvy

poor formation of collagen in blood vessels weak vessels result in hemorrhages can be severe and result in lots of blood loss and death

Toxicity: may result in kidney stones rebound scurvy Destruction of B12 Problems with acid/base balance

Vitamin C: RDA 90/75 mg/day Foods rich in vitamin C:

1 cup fresh squeezed orange juice: 124 mg 1 cup canned o.j.: 84 mg

Smoker’s RDA = +35 mg/day Some of vitamin C is sacrificed in reducing

the oxidants of cigarette smoke Vitamin C intake offers protection against s

tomach cancer

Beta-Carotene-provitamin Functions

Weak antioxidant Enhance immune system Protect skin and eyes

Deficiency/toxicity

Beta-Carotene-provitamin No RDA Sources

Vitamin A Functions Vision: helps with conversion of light

energy to electrical energy in eye Cell differentiation-maintenance of linings:

helps produce the CHO normally found in mucous

Bone growth: helps with remodeling growing bones

Vitamin A Deficiency One year supply in fat and liver of most people:

So deficiencies are rare Bone growth and remodeling problems

shape changes

Linings deteriorate GI tract: diarrhea Respiratory tract: infections urogenital tract: infections, kidney stones

Impaired night vision and day vision

Vitamin A Toxicities Bones:

decalcification, joint pain

Nervous system loss of appetite, irritability, muscle weakness

Liver enlargement jaundice

Blood: RBCs loose hemoglobin Bleeding induced easily

Beta carotene and Vitamin A

Vitamin A RDA= 700 RE for females; 900 RE for males. RE= Retinol Equivalent

Retinol is the active form of vitamin A Other molecules can be metabolized to make Retinol,

thus retinol equivalents e.g.: beta carotene can be modified to make retinol beta carotene is found in carrots and other deep orange and

green vegetables 1 RE= 1 microgram of retinol 1 RE= 3.3 IU retinol 1 RE = 12 micrograms of beta carotene

Selenium Functions

Antioxidant system Thyroxine and immune function

Deficiency Keshan disease Impaired immune response, cognitive function,

muscle pain, wasting The Link between Selenium and Chemopreventio

n: A Case for Selenoproteins -- Diwadkar-Navsariwala and Diamond 134 (11): 2899 -- Journal of Nutrition

Selenium – RDA 55 mg/day Sources Nuts Seafood Pasta

Disorders related to Oxidation Cancer - Definitions Cancer: uncontrolled growth and spread of

abnormal cells Tumor: mass of cancer cells

benign tumor (non-harmful, non-invasive) malignant tumor (harmful, invasive)

Metastatic Cancer: spreading

Cancer Facts US men have a 1 in 2 lifetime risk US women have a 1 in 3 lifetime risk 1,220,000 new malignant cancer cases in

2000 552,000 cancer deaths in 2000 Cancer the Top Killer for Those Under

85 – Jan 20, 2005

Cancer TrendsJNCI, 1999

1990-1996 All cancer incidence declined by

2.2% -4.1% males -0.5% females USATODAY.com - Cancer deaths

lowest in 7 decades

US Mortality, 2000

Source: US Mortality Public Use Data Tape 2000, National Center for Health Statistics, Centers for Disease Control and Prevention, 2002.

1. Heart Diseases 710,760 29.6 2. Cancer 553,091 23.0

3. Cerebrovascular diseases 167,661 7.0 4. Chronic lower respiratory diseases 122,009 5.1 5. Accidents (Unintentional injuries) 97,900 4.1 6. Diabetes mellitus 69,301 2.9 7. Influenza and Pneumonia 65,313 2.7 8. Alzheimer’s disease 49,558 2.1 9. Nephritis 37,251 1.5

10. Septicemia 31,224 1.3

Rank Cause of DeathNo. of deaths

% of all deaths

2004 Estimated US Cancer Deaths*

ONS=Other nervous system.*Excludes basal and squamous cell skin cancers and in situ carcinomas except urinary bladder.Source: American Cancer Society, 2003.

Men285,900

Women270,600

25% Lung & bronchus

15% Breast

10% Colon & rectum

6% Pancreas

6% Ovary

4% Leukemia

3% Non-Hodgkin lymphoma

3% Uterine corpus

2% Brain/ONS

2% Multiple myeloma

Lung & bronchus 32%

Prostate 10%

Colon & rectum 10%

Pancreas 5%

Leukemia 5%

Non-Hodgkin 4%lymphoma

Esophagus 4%

Liver/intrahepatic 3%bile duct

Urinary bladder 3%

Kidney 3%

The Cancer Development ProcessInitiation Alterations in DNA minutes - days Causes:

radiation chemical carcinogens viruses

The Cancer Development Process

Promotion “locking” DNA alterations failure of DNA repair

mechanisms months - years

The Cancer Development Process

Cancer Progression Uncontrolled growth of cancer

cells malignancy and metastasis weeks to years

Cancer DevelopmentCancer Development

http://science.education.nih.gov/supplements/nih1/cancer/activities/activity2_animations.htm

Diet and Cancer Development Initiation Dietary sources of carcinogens

aflatoxin mold from peanuts benzopyrene from charbroiled meats nitrosamine from cured meats

AICR Press Corner - Recent News Protection

phytochemicals antioxidants dietary fiber Study will assess effect of tomato oil on precancerous prostate

changes

Diet and Cancer Development Promotion

Fat and PUFA excess alcohol

Progression excess Fat and calories Alaska Journal of Commerce Online

Diet and CancerACS 2000

One third of cancer deaths in US is due to cigarette smoking

One third of cancer deaths in US is due to diet

5-10% of cancers are hereditary NutraIngredients

1999 ACS Dietary GuidelinesChoose most of the foods you eat from plant

sources. Five A DayHealthy fruit and veg compounds being lost in

processing low in fat and calories high in folic acid, vitamin C, beta-carotene high in fiber high in phytochemicals ABC News: Turn to Tomatoes for Prostate Health FOXNews.com - Health - Vitamin D May Lower Some

Cancer Risk

Trends in Consumption of Recommended Vegetable and Fruit Servings (5 or more) for Cancer Prevention, Adults 18 and Older, US, 1994-2000

* Includes fewer than 50 states and the District of Columbia. All other prevalences include the 50 states and District of Columbia.Source: Behavioral Risk Factor Surveillance System, 1994, 1996, 1998, 2000, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, 1997, 1999, 2000, 2001.

Prevalence (%)

2224 24 23

0

5

10

15

20

25

30

35

1994*

1996 1998 2000

Cardiovascular Disease (CVD) Risk factors

Smoking Hypertension High LDL Obesity Sedentary life style Nutrition Notes: How to fight inflammation -

Nutrition Notes - MSNBC.com

CVD and Antioxidants Scavengers

Donates electrons Reduction of inflammation

Enhances immune system Reduction of blood coagulation

Vision impairment Macular degeneration

Promising results Cataracts

Mixed results