Chapter 9: Fat-soluble Vitamins (Vitamin D) Flashcards
other names:
-antirachitic factor
-cholecalciferol (vitamin d3)
-ergocalciferol (vitamin d2)
-calcitriol calcidiol
vitamin d
vitamin d2
ergocalciferol
vitamin d3
cholecalciferol
vitamin d - chemistry
exists in 2 forms in foods
vitamin d3: cholecalciferol
vitamin d2: ergocalciferol
vitamin d - chemistry
source of vitamin d3 (cholecalciferol)
animal products
vitamin d - chemistry
source of vitamin d2 (ergocalciferol)
vitamin d-fortified foods
vitamin d - chemistry
generic name of vitamin d3 and vitamin d2 is
calciferol
vitamin d - chemistry
can be considered as a _____ and _____ (can be synthesized in the body)
vitamin and hormone
vitamin d - chemistry
vitamin d3 is produced in the skin by ultraviolet irradiation (sunlight) to _____, a metabolite of cholesterol
7-dehydrocholesterol
vitamin d - absorption, transport, and utilization
- dietary vitamin d is absorbed in the _____
small intestine
vitamin d - absorption, transport, and utilization
dietary vitamin d is absorbed in 1. the small intestine with the aid of _____ and incorporated within chylomicrons
bile
vitamin d - absorption, transport, and utilization
- cholecalciferol from the skin mixes with the blood and is transported by _____, and goes to the liver
vitamin d-binding protein
vitamin d - absorption, transport, and utilization
- cholecalciferol from the skin mixes with the blood and is transported by vitamin d-binding protein, and goes to the _____
liver
vitamin d - absorption, transport, and utilization
- cholecalciferol, reaching the liver from any of the 2 sources, is hydroxylated to _____ aka 25-hydroxycholecalciferol
25-hydroxyvitamin D
vitamin d - absorption, transport, and utilization
- _____ start to form active vitamin D when the parathyroid hormone blood level rises as a result of the decrease in blood calcium or phosphorous level
kidney
vitamin d activation site
liver
vitamin d storage site
adipose tissue
rich with vitamin D receptors and play a major role in turning vitamin D into its active form
kidney
vitamin d - absorption, transport, and utilization
conversion of vitamin is activated by
parathyroid hormone blood level
vitamin d - absorption, transport, and utilization
calcium and phosphorous absorption in the _____; 1, 25 (OH) D3 stimulating the mobilization of Ca and P form the bone and bringing about renal reabsorption of Ca are the effects of the activation of vitamin d
intestine
vitamin d - relationship with other nutrients
vitamin d metabolism is interrelated with _____, _____ and _____, and _____
calcium; phosphorous and parathyroid hormone; calcitonin
vitamin d - relationship with other nutrients
one of the main roles if vitamin d is to facilitate _____
calcium and phosphorous absoprtion
vitamin d - relationship with other nutrients
low vitamin d levels result in a decreased formation of the active vitamin leading to _____
bone calcium resorption
active form of vitamin d
1,25-dihydroxycholecalciferol
active form of vitamin d is 1,25-dihydroxyvitamin aka
calcitrol
vitamin d - relationship with other nutrients
_____ deactivates the production of active vitamin d
high phosphorous
vitamin d - relationship with other nutrients
_____ needed in the formation of calcium-binding proteins present in the target tissues activated by vitamin d
vitamin k
vitamin d - functions
regulates _____ and _____ homeostasis involved in bone formation and maintenance
calcium and phosphorous
vitamin d - functions
promotes normal bone mineralization by making calcium and phosphorous available in the blood that is deposited as the _____ harden
bones
vitamin d - functions
regulating specific genes by affecting _____ transcription rate
chromosomal
vitamin d - functions
some of the target tissues include ______ (5), beneficial in treating cancer
brain
pancreas
skin
muscles and cartilage
reproductive organs
vitamin d - deficiency
among children
characterized by soft and fragile bones, enlarged joints, bowed legs, and deformities of the chest, spine, and pelvis
rickets
vitamin d - deficiency
among adults
happens when there is not enough calcium in the body and is characterized by softening of the bones
osteomalacia
vitamin d - deficiency
among adults
refers to the loss of calcium from the bones causing reduced bone density
osteoporosis
vitamin d - deficiency
-alcoholic
-insufficient sun exposure
-with intestinal disorders (tropical sprue, crohn’s disease, diverticulosis, gastric resection)
-liver and renal disease
-parathyroid disorder
-those taking anticonvulsant drugs
-sedative
-tranquilizers
-preschoolers
-elderly
population at risk for developing vitamin d deficiency
vitamin d - toxicity
calcification of the kidneys and lungs, nausea, weight loss, and polyuria
hypervitaminosis a
vitamin d - recommended intake
for infants to adults (0 - 49 y/o) male and female
5 ug
vitamin d - recommended intake
for adults (50-59 y/o) male and female
10 ug
vitamin d - recommended intake
for adults (60- >70 y/o)
15 ug
vitamin d - recommended intake
daily intake of _____ is adequate to protect against rickets and promote normal bone growth, provided that the diet is also sufficient in Ca and P
100 IU
vitamin d
fish liver oils, butter, clams, oysters, eggs, sardines, and vitamin d-fortified foods (milk and margarine)
common sources of vitamin d
