Ch 8: Nutrients + Antioxidant Function Flashcards
What are examples of antioxidents (5)
- Vit E
- Vit C
- Beta carotene
- Vit A
- Selenium
oxidation vs reduction
oxidation- loss of electrons from a molecule
reduction- gain of electrons from a molecule
What is a free radical
an atom that has lost an electron and is left w an unpaired electron
- can cause damage in the body as they reactite with oxygen
How can free radicals be produced in the body (4)
- normal processes (prob is when we cant deal w em)
- Pollution
- UV light and radiation
- Toxic substances
What can free radicals cause damage to (4)
- Cell membranes
- Low density lipoproteins
- proteins in the cell
- genetic material (DNA)
What enzyme systems do antioxidents act on (3)
- Superoxide dismutase
- catalase
- glutathione peroxidase
What is the biologically active and inactive form of Vit e and RDA
Active- Tocopherol
Inactive- Tocotrienol
RDA-15mg/day
What are the functions of Vit E
- Primar role as antioxident
- Protects Polyunsaturated Fatty Acids
- Protects low-density lipopros
dangers of overconsumption of Vit E
- Interfere w anticoagulent meds
- Nausea/diarrhea
- Link to vasular diseases/heart failure
Function of Vit C and RDA
- Antioxident
- synthesis of collagen
- prevent scurvy
- enhances immune system
RDA- 90mg/day men, 75mg/day women
dangers of overconsumption of Vit C
- nausea, diarrhea
- iron toxicity
- kidney stone formation in people w/ kidney probs
Main risk of underconsumption of vit C and complications associated
Scurvy
- bleeding gums, loose eeth, weakness
- can occur after 1 month
What is betacaroene considered and what is it a precurser to
carotenoid (provitimin- inactive precursors that must be converted to the active form in body)
Precursor to retinol
Functions of beta carotene anf RDA
- Weak antioxident
- effective against oxidation in cell membranes + LDLs
- Enhance immune system
- Protect skin from damage by UV light
No RDA established (not considered essential)
What happens if you overconsume + underconsume beta carotene
too much- dont appear to be toxic
too little- No known deficiency symptoms
What are the 3 active forms of Vit A
Retinol
Retinal
Retinoic acid
–all collectively known as the retinoids
Function of Vit A
- Vision
- sex repro
- bone health
- immune function
- cell differentiation
- antioxident (protect LDL)
RDA of vit a (men + women)
men 900mg/day
women- 700mg/day
What occurs if you consume too much VIt A
- birth defects
- spontaneous abortion
- permentent damage to liver/eyes
What happen if you dont consume enough vit A
Night blindness
-irreversivle blindness (xerophthalmia)
Selenium functions, RDA
- Antioxident (glutathione peroxidae enzyme system)
- Production of thyroxine
55ug/day
What happens if you consume too much selenium
selenium toxicity- brittle hair, nails, skin rashes
What happens if you dont consume enough selenium (2)
Keshan Disease- Form of heart disease
Kashin Beck- type of arthritis
What 3 nutrients are cofactors for superoxide dismutase enzyme antioxidant system
Copper, Zinc, manganese
What nutrient is a cofactor for the catalase antioxidant systme
Iron
What are the 3 steps of cancer
Initiation- cells DNA is mutated
Promotion- Altered cell repeatly divides
Progression- cell grow out of control
top 5 modifiable risk factors to cancer
- Tobacco
- nutrition+fitness
- Alcohol
- Uv rd
- Vit D
How can antioxidents reduce cancer risk
- enhancing immune system
- inhibiting the growth of cancer cells
- preventing oxidation damage
