VITAMIN E

One of the most misused and controversial nutrients because of many erroneous claims for its healing powers in variety of ailments

Discovery

1922- female rats and male rats were sterile unless lettuce wheat germ and dried alfalfa were added to their diet

1924- called this fertility vitamin, vitamin E 1936 - vitamin E was isolated from wheat germ oil and called it alpha

tocopherol greek of child-birth and to carry

Absorption and metabolism

Best absorbed on the presence of fat Conditions that interfere with fat absorption:

o Bilary tract diseaseo Pancreatic insufficiencyo Excessive mineral oil digestion

Intestinal absorption is between 20-30% Vitamin enters lymph unchanged Attaches to lipoproteins as they are being transported to

bloodstream and become tocopherol Stored in:

o Adipose tissueo Muscleo Liver

(in smaller amounts):

o Hearto Uteruso Testeso Adrenals

Function

Antioxidant- limits free-radical chain reactions Protect body cells from lipid peroxidation Make cell membranes more stable Prevents fat from becoming rancid

**vitE requirement is proportional to the amount and the degree of unsaturation of polyunsaturated fatty acid in diet = less polyunsaturated fat, less vitE required

Deficiency

Rare If present, due to congenital or malabsorption disease Anemia - For premature infants born w/ inadequate reserve of vitE

Treatment

30-100mg daily may be prescreibed Minor symptoms such as mausea and intestinal distress appears

when ingesting 300IU per day

Food Sources

Seed oils = major source wheat germ oil vegetable oils nuts and seeds

whole grains egg yolk leafy green vegetables

Toxicity

large doses may increase time required for blood coagulation symptoms:

o headacheo fatigueo weaknesso blurred visiono temporary nauseao flatulenceo diarrhea

VITAMIN K

1931 – chickens were protected from bleeding when they were fed fish meal that was not extracted with ether

1935 – found that VitK was essential for blood coagulation

Chemistry

Derivative of 2-methyl-1,4-napthoquinone K1 & K2

o Natural formso Yellowish olso Unstable in UV lighto Easily destroyed by strong acids and alkaliso K1 – occurs in green plantso K2 - produced by bacterial synthesis in intestineo K3 – menadione; synthetic form of VitK

Absorption

Requires bile and pancreatic juice Can also be synthesized by bacteria in GI tract in jejunum and

ileum

Function

Aids in blood clotting (main function) Assist in Ca+ absorption Lowers risk of kidney stones

Deficiency

Rare Only occurs in individuals with GI disorders **breastfed infants have VitK due to immaturity of liver and

thus newborn babies are given Vit K suppelements and aor the mother is requested to eat recommended amount of green leafy vegetables daily

Food Sources

Spinach Broccoli Cabbage Lettuce Vegetable oils