Ch 9: Nutrients involved in bone health

Question 1

What makes up the structure of bone

Answer 1

65% minerals -providing hardness
35% orgainic structures for strength, durability and flexibility
Collagen- fibrous pro in bone

Question 2

What are the metabolic processes associated with bone + what does it store(3)

Answer 2

• Acts as storage reseviour for minerals such as calcium, phosphorus and fluoride
• bone marrow produces new blood cells

Question 3

When is bone growth completed in males and females

Answer 3

14 in girls

17 in boys

Question 4

What is the most accurate way to to assess bone density and who is it recommended for

Answer 4

DEXA scan

-recommended for post menopausal women mainly

Question 5

Where is most calcium found in the body

Answer 5

99% found in bone

1% remaining is found in blood/soft tissues

Question 6

What occurs when there is low calcium levels

Answer 6

Parathyroid horomone release which stims activation of Vit D

Question 7

What does PTH and vit D cause

Answer 7

• kidneys to retain more calcium
• osteoclasts to break down bone to release calc
• stims calc absorption in intestines

Question 8

What occurs when there is high calcium levels

Answer 8

thryroid releases calcitonin

Cacitonin functions to:

• prevent calcium reabsorbtion
• limit absorption in intestines
• inhibit osteoclast breakdown

Question 9

bioavailibity of calcium in children, preg women, adults, older adults

Answer 9

children- 60%
preg- 50%
adults-30%
older- 25%

Question 10

max absorbed amount of calcium @ one time

Answer 10

500mg

Question 11

what occurs when you consume too much calcium and what can it be caused by

Answer 11

Hypercalcemia can be caused by cancer + overprod of PTH

-calcium supplementation can compete with absorption of iron/zinc/magnesium

Question 12

What can low blood calcium be due to

Answer 12

can be caused by kidney diease or overproduction of PTH

Question 13

What is vitamin d technically

Answer 13

technically a horomone as it is synthesized in one location and acts upon another
-synthesized by UV light

Question 14

Functions of Vit D

Answer 14

• Regulates blood calc
• Required for calc + phosphorus absorption
• Stims osteoclasts
• Necessary for calcification of bone

Question 15

RDA for adults + ind over 70

Answer 15

15ug day

20ug day over 70

Question 16

Why does overconsumpton of Vit D happen and what does it cause

Answer 16

occurs from vit supplements (not excessive exposure)

-results in hypercalcemia

Question 17

What happends if you dont consume enouch vit D (2) and what causes it

Answer 17

-Occurs w diseases that reduce intestinal absorbtion of fat/limited sun exposure

Rickets- inadequate minerization in nine
Osteomalacia- loss of bone mass in adults

Question 18

What is the plant form and large intestine form of Vit K

Answer 18

plant form- Phylooquinone

Intestine by bacteria- Menaquinone

Question 19

Function of vit K (2) + RDA

Answer 19

• Blood coagulation
• Bone metabolism

RDA- no RDA for vit K

Question 20

What happens if you overconsume/underconsume vit K

Answer 20

too much- no side effects

too little- reduced blood clotting/excessive bleeding
occurs w diseases that limit absorption of fat

Question 21

Function of Phosphorus and RDA

Answer 21

• Critical to mineral composotion of bone
• required for proper fluid balance
• component of ATP, DNA, membranes

RDA= 700mg/day

Question 22

What occurs in excess phosphorus consumption and why does it happen

Answer 22

Excesive vit D sups or consumption of too many phosphus containing antacids

-mm spasms, convulsions

Question 23

Where is most magnesium found and functions

Answer 23

50-60% found in bone

• mineral found in bone structure
• cofactor for over 300 enzyme systems
• required for production of ATP, DNA, Pros

Question 24

RDA of magnesium

Answer 24

310-420mg/day

Question 25

What occurs if you dont get enough magnesium

Answer 25

hypomagnesemoa- result in low blood calcium/osteoporosis

-mm cramps, spasms, nausea, weakness, confusion

Question 26

Function of fluooride and RDA

Answer 26

• Development + maintenance of teeth/bones
• combines with calcium and phosphorus to make tooth enamel stronger

No RDA

Question 27

What happens if you overconsume/unerconsume fluoride

Answer 27

over- fluorosis- creates porous tooth enamal

under- cavities

Question 28

How is age a risk factor for osteoperosis

Answer 28

• bone mass decreases w age
• reduced estrogen/test lvls
• older adults less able to absorb vit D

Question 29

Why does sex play a role in osteoperosis

Answer 29

• women have lower bone density

- estrogen lower in post metopausal women

Question 30

The progression of osteoperosis may be slowed by

Answer 30

• adequate calcium + vit D intake
• Reg exercise
• antiresorptive medications
• horomone replacement therapy