B Vitamins Flashcards
Thiamin Major Functions
part of a coenzyme
- aids in the breakdown to provide energy
- needed to convert pyruvate into acetyl-CoA
thiamin is a coenzyme is especially important for nerve function
thiamin occupies a special site on nerve cell membranes; hence it is available to breakdown any needed glucose
thiamin is needed for the synthesis of …
neurotransmitters
thiamin is needed for the metabolism of
other sugars and amino acids
thiamin is required for the synthesis of
ribose and deoxyribose
Beriberi
deficiency disease of thiamin
- inflammatory or degenerative changes of the nerves, digestive system and the heart
- without thiamin, glucose can’t be used normally
- nerve impulses can’t be transmitted
symptoms of beriberi
loss of sensation in the hands and feet, edema, muscle weakness & poor coordination, changes to the heart, poor short-term memory and confusion
alcoholics at risk for beriberi
ethanol intereferes with the absorption of thiamin and hastens is excretion in the urine
Riboflavin
is a part of two coenzymes
- that act as electron carriers
- they function in reactions needed to produce ATP from CHO, fat and protein
Riboflavin is involved n converting some vitamins into their active form
such as folate, niacin, vitamin B6, and vitamin K
Riboflavin supports
skin health and vision
symptoms of riboflavin deficiencies
cheilosis - cracking & redness of the lips or around the corners of the mouth
- flaking skin around the nose, eyebrows & earlobes
- glossitis - inflammation of the tongue (red & swollen)
- eyes - increased sensitivity to light; burning, tearing, and itching of the eyes
Niacin
is part of two coenzymes
- especially in the metabolism of CHO, fat, and alcohol
- coenzymes needed for the synthesis of fatty acids and cholesterol
body can make niacin from
tryptophan
-reason why recommendation are expressed as “niacin equivalent”
Niacin Equivalent
the measure that takes into account the available tryptophan
Pellagra
niacin deficiency diseases
-fatigue, decreased appetite, and indigestion
Symptoms of Pellagra (the four D’s)
Diarrhea, Dermatitis, Dementia and it left untreated Death
those at risk for Pellagra
poorly nourished, those with alcohol addiction
Niacin is sometimes prescribed in larger doses as a treatment for
lower blood lipid levels
Biotin
plays an important role in energy metabolism
-as a coenzyme, it carries activated CO2 that is critical in keeping Citric Acid Cycle running.
Biotin is needed in the synthesis of glucose
from non-carbohydrate sources such as amino-acids and glycerole