Vitamins General Flashcards
Coenzyme
organic non-protein substance that binds to an enzyme to promote activity of the enzyme with which it is bound
Vitamin
essential macronutrient
needed in only small amounts
organic compounds
Role of Vitamins in the body
promote and regulate body processes necessary for growth, reproduction, maintenance of health and life
Vitamins are divided into two groups of solubility
Water-soluble
fat-soluble
water-soluble vitamins
B vitamins, Vitamin C
Fat-Soluble vitamins
Vitamins A, D, E, and K
where are vitamins found?
naturally in food groups, including oils
which food groups lacks B12?
grains, fruits, vegetables
which food groups lack Vitamin C?
grains, dairy, protein
fortification
gov’t mandated to address macronutrient deficiences
voluntary fortification
NOT MANDATED
increased risk for exceeding tolerable upper intake limits
what helps to release vitamins from food
Mouth - mechanical digestion
stomach - chemical digestion
vitamin absorption mainly takes place in the….
small intestine, aided by pancreatic digestive enzymes
water-soluble vitamins need assistance to be absorbed by mucosal cells
transport system (energy needed) or bind to specific molecule -once absorbed, able to directly into bloodstream.
fat-soluble vitamins absorption happens through…
micelles and chylomicrons
fat soluble vitamins absoprtion - micelles
- products of fat digestion
- bile surrounds these droplets
- facilitates absorption (simple diffusion)
fat soluble vitamins absorption - chylomicrons
comprised of newly reassembled TGs, cholesterol, fat-soluble vitamins that are packaged with phsopholipids and proteins
- too big to enter capillaries
- enter lymphs
- delivers TG to cells in body
What happens in the large intestine?
bacteria can make a small amount of vitamins
bioavailibility
extend to which the body can absorb and use a nutrient
vitamin bioavailability is influenced by
- composition of diet
- conditions of the GI tract
- rest of the body (too low fat diet and not enough circulating blood proteins)
some vitamins are absorbed in an inactive form
provitamins or vitamin precursor: compound in inactive vitamins that us converted to active form in the body
antioxidant
substance that decreases adverse effects of reactive molecules on normal physiological functions. they protect against oxidative damage
highly reactive molecule
damage caused by highly reactive molecules that steal electrons from other compounds, causing changes in structure and function
free radical
type of highly reactice molecule