Unit 2 - Nutrition Therapy & Supplementation for Osteoporosis

Question 1

What does bone metabolism (AKA bone remodeling) play an important role in?

Answer 1

plays an important role in building and maintaining the skeletal system and teeth, which requires vitamins, minerals, and hormones working cooperatively to maintain healthy bones.

Question 2

However, imbalances in bone metabolism can occur in some people who develop _______.

Answer 2

osteoporosis

Question 3

What is bone remodeling & when does it occur?

Answer 3

The growth and maintenance of bones (bone remodeling) occurs when old bone tissues are resorbed/removed and replaced by new tissues, which is important for repair and reshaping of bones after fractures or micro cracks due to stress.

Question 4

What is crucial for bone remodeling?

Answer 4

The interactions of several nutrients, calcium, phosphorous, magnesium and fluoride; vitamins, vitamins A, D, and C; and hormones, parathyroid hormone (PTH) and calcitonin, are crucial for bone remodeling.

Question 5

The hormonal control of bone remodeling that take place at the genetic level, leads to…

Answer 5

the activation of signalling pathways in bone cells that affect their growth, survival, differentiation and functions.

Question 6

What are the signalling pathways under investigation?

Answer 6

include the beta-catenin and receptor activator of nuclear factor kappa-beta ligand (RANKL)/ receptor activator of nuclear factor kappa beta (RANK) pathways

Question 7

What are the 3 main types of bone cells?

Answer 7

• Osteoblasts
• Osteocytes
• Osteoclasts

Question 8

Osteoblasts:

Answer 8

are bone formation cells that synthesize the protein collagen matrix and deposit minerals, including calcium and phosphorous/phosphate, into the protein matrix (calcification).

Question 9

Osteocytes:

Answer 9

that represent most of the bone cells are matured osteoblasts, which are entrapped in the protein matrix that they produced. They send signals to osteoblasts to build new bone tissues in response to stress. For example, weight-bearing physical activity, which results in micro cracks.

Question 10

Osteoclasts:

Answer 10

are bone-removing cells that secrete hydrochloric acid to dissolve the calcified minerals, and enzymes collagenase and acid phosphatase to lyse the bone protein matrix.

Question 11

What is the hormonal control of bone metabolism?

Answer 11

Calcium and phosphorous are part of the bone structure. When there is decrease in blood calcium and phosphorous, they are mobilized from the bones into the blood. The blood concentrations of these minerals are under control of the parathyroid hormone (PTH), vitamin D, calcitonin, and other hormones.

Question 12

What do the Parathyroid hormone (PTH), vitamin D, calcitonin, & other hormones play a major role in?

Answer 12

These hormones play a major role in the resorption, reabsorption, absorption, and excretion of calcium and phosphorous from the kidneys, bones, and intestine

Question 13

Parathyroid hormone:

Answer 13

tends to increase calcium and phosphorous concentrations in the blood, by promoting the resorption of bones, synthesis of active vitamin D in the kidney, and reabsorption of calcium in the kidneys.

Question 14

Vitamin D/calciferol:

Answer 14

is actually a hormone because it is not an essential nutrient from foods. Given enough sun, the body can synthesize vitamin D. Vitamin D stimulates the breakdown (resorption/mobilization) of bone tissues to release calcium and phosphate into the blood, absorption of calcium from the intestine, and reabsorption of calcium in the kidneys.

Question 15

Calcitonin:

Answer 15

in contrast to vitamin D and PTH, tends to decrease the concentration of plasma calcium by reducing calcium uptake in the kidneys, and stimulating calcification (the deposition of calcium and other minerals) into the protein matrix of bone tissues.

Question 16

Vitamin D, PTH, and calcitonin elicit their actions of affecting calcium and phosphate blood concentrations, by their effects on the bone cells:

Answer 16

• Parathyroid hormone (PTH)
• Vitamin D
• Calcitonin

Question 17

Parathyroid hormone (PTH):

Answer 17

increases osteoclast activity.

Question 18

Vitamin D:

Answer 18

increases osteoclast activity.

Question 19

Calcitonin:

Answer 19

increases osteoblast and osteocyte activities.

Question 20

In addition, _______, _______, & _________ inhibit osteoclast activity

Answer 20

• estrogen
• growth hormone
• testosterone

The effects of these hormones on the cells lead to bone remodeling

Question 21

What can happen in postmenopausal women?

Answer 21

there is an increased risk of osteoporosis; women loose bone mass and are high risk of bone fractures. So do middle-aged and older men.

Question 22

When do people develop osteoporosis?

Answer 22

People develop osteoporosis when their bone loss becomes extreme such that bone fractures occur under ordinary everyday stresses.

Question 23

What is the prevalence of osteoporosis & what is it associated with?

Answer 23

It is more prevalent in women and is associated with increased mortality and morbidity due to complications from bone fractures.

Question 24

Both _____ and _______ factors contribute to osteoporosis

Answer 24

• genetic
• environmental

Question 25

The risk factors for osteoporosis include:

Answer 25

reduced peak bone mass and previous fractures, and others listed below.

These risk factors can be either non-modifiable or modifiable.

Question 26

Non- modifiable factors include:

Answer 26

female gender, older age, small and thin body frame, ethnicity (Caucasian, Asian, Hispanic/Latino heritage, or African America Women), and family history of osteoporosis, estrogen and testosterone deficiency.

Question 27

Modifiable risk factors include:

Answer 27

sedentary lifestyle (lack of physical exercise), nutritional risk factors (inadequate intake of minerals and vitamins essential for bone growth and maintenance), and lifestyle (tobacco use, alcohol abuse) and certain medications (glucocorticoids and anticonvulsants).

Question 28

Apart from calcium, phosphorous, vitamin D, magnesium, fluoride, and vitamins K, C, and A are involved …

Answer 28

maintaining bone health

Question 29

______ & __________ put stress on bones that are important in building new bone tissues

Answer 29

Physical activity and weight training

Question 30

Except for vitamin D, we obtain _____ and ______ from animal and plant foods.

Answer 30

• calcium
• phosphorouos

Question 31

What is the food group most associated with bone health?

Answer 31

calcium
- dairy group (milk & milk products)

Question 32

What does the calcium group provide?

Answer 32

provides a rich source of calcium, between 20% and 75% of recommended calcium, protein, phosphorous, magnesium, and potassium

Question 33

What foods are rich in calcium?

Answer 33

Vegetables including beet greens, green cabbage, broccoli, and turnip greens are good sources of available calcium. Collard greens, parsley, and watercress, and beans and almond are also rich in calcium. Some vegetables including spinach and Swiss chard although are calcium rich but provide very little, because they contain binders that prevent calcium absorption. Breakfast cereal, fruit juice, and mineral water are fortified with calcium.

Question 34

What foods are rich in phosphorous?

Answer 34

Although milk and milk products are rich sources of phosphorous, animal protein (meat, poultry, and eggs) and fish are the best sources of phosphorous. Phosphorous is abundant in most foods. A balanced diet in calcium and protein has adequate amounts of phosphorous, because all three nutrients are present in the same foods.

Question 35

What foods are rich in Vitamin D?

Answer 35

Exposure to sunlight can provide enough amount of vitamin D in our body. However, additional food sources are necessary in most cases to satisfy the recommended dietary allowance (RDA). Only a few animal foods (eggs, liver, and butter) and some fatty fish (salmon and sardines) contain a significant amount of vitamin D. Some foods including milk and margarine are good sources of fortified vitamin D.

Question 36

Is there a cure for osteoporosis?

Answer 36

no

Question 37

______ is an important component for treating individuals with osteoporosis.

Answer 37

Nutrition

Question 38

____ may be the most crucial complement to drugs for combination therapy.

Answer 38

Diet

However, for individuals at risk of osteoporosis, the more important role of diet is prevention or slow disease progression.

Optimal protection of bone health partly depends on adequate intake of nutrients. The adequate intake of essential nutrients for bone health, and enough exposure to sunlight, is important at all stages of life

Question 39

The key recommendation from Health Canada for the prevention of osteoporosis or slowing down bone loss is…

Answer 39

adequate dietary intake of calcium and vitamin D to obtain the RDA, which depends on age and sex (Table 2) amongst other factors.

Question 40

Large prospective studies has shown that ______ deficiency is associated with severity of osteoporosis in elderly and postmenopausal women.

Answer 40

vitamin D

Question 41

Vitamin D fortified foods have significant effect on…

Answer 41

increasing bone mineral density (BMD) and serum level of vitamin D and decreasing PTH levels in people with prior vitamin D deficiency.

Question 42

However, vitamin D has no significant beneficial change on…

Answer 42

bone turn over markers (BTM).

Question 43

The beneficial effects of vitamin D on fractures (reduction in lumbar spine, hip, and total body fractures) and on bone mineral content (BMC), depend on…

Answer 43

vitamin D deficiency status, ethnicity, sex, age, nutrient components of diet, and lifestyle choices.

Question 44

In general, ______ can have a positive effect on bone density and health. However, the beneficial role of dairy products in preventing fractures is uncertain and controversial

Answer 44

dairy products

Question 45

The reviews, meta-analysis, and current studies about the effects of different dietary patterns are consistent with the observations that the __________ is beneficial for bone status when compared to the Western diet (a control diet used in interventional trials).

Answer 45

Mediterranean diet

Question 46

Vegetarian diets:

Answer 46

contain lower amounts of calcium, vitamin D, vitamin B12, protein and omega-3 fatty acids, all of which have important roles in maintaining bone health.

Question 47

However, healthy vegetarian diets usually contain greater quantities of several protective bone-related nutrients such as…

Answer 47

magnesium, potassium, vitamin K, and antioxidant and anti-inflammatory phytonutrients.

Question 48

Nevertheless, the limited amount of studies done so far suggest that ______ may be at higher risk of low BMD and fractures.

Answer 48

Vegans

Question 49

Dietary patterns including fruit, vegetables, whole grains, poultry, fish, nuts and legumes, milk and dairy products will be beneficial for…

Answer 49

bone health, decreasing the risks of osteoporosis and fractures.

Question 50

Why is getting calcium and vitamin D from foods better than dietary supplements?

Answer 50

Getting calcium and vitamin D from foods is better than dietary supplements because food offers fringe benefits of supplying substantial amounts of other nutrients, which can also enhance the absorption of both calcium and vitamin D.

Question 51

Some people also absorb vitamin D and calcium better from ____ than _____

Answer 51

food than supplements.

Question 52

Supplements are usually recommended when intake from food for calcium and vitamin D are ______

Answer 52

insufficient

Question 53

Who should take calcium and vitamin D supplements?

Answer 53

Inclusion of calcium and vitamin D supplements to complement their dietary levels may be indicated for the following groups:
Patients who have inadequate intake of milk and milk products (including those who are lactose intolerant); older adults, >70 years of age, with limited sun exposure; post-menopausal women at higher risks of osteoporosis; infants and children up to three years with specific risk of osteoporosis; and pregnant women. Also, those following a vegan diet; are receiving long-term treatment with corticosteroids; and have certain bowel or digestive diseases that decrease their ability to absorb calcium, such as inflammatory bowel disease or celiac disease, may take calcium and vitamin D supplements.

Question 54

The recommendations for calcium & vitamin D supplements should consider the _________, which is the maximum daily dose that is less likely to cause toxicity (Table 3), and the following specific instructions

Answer 54

Tolerable Upper Intake Level

Question 55

Calcium supplements:

Answer 55

Several different kinds of calcium compounds are used in calcium supplements. Each compound contains varying amounts of elemental calcium. Common calcium supplements may be labeled as calcium carbonate (40% elemental calcium); calcium citrate (21% elemental calcium); calcium gluconate (9% elemental calcium); and calcium lactate (13% elemental calcium).

Question 56

The two main forms of calcium supplements are _______ & ________

Answer 56

calcium carbonate and calcium citrate.

Question 57

The doses should be based on the elemental calcium and not calcium salt:

Answer 57

Calcium carbonate should not be consumed with food, but calcium citrate supplements can be taken with or without food.

The doses should be divided into three parts, each 400-500 mg/dose, and taken to reach 1200- 1500 mg/day.

Question 58

Vitamin D supplements:

Answer 58

Osteoporosis Canada recommends supplementation of 400 to 1000 IU of vitamin D daily for all healthy adults 19 to 50 years of age (including pregnant and breastfeeding women). Supplementation of 800 to 2000 IU of vitamin D daily is recommended for those over the age of 50 or younger adults at high risk (with osteoporosis, multiple fractures, or conditions that may affect vitamin D absorption). To achieve optimal vitamin D status, daily supplementation with more than 1000 IU (25 μg) may be required. Daily doses up to 2000 IU (50 μg) are safe and do not necessitate monitoring. For individuals receiving pharmacologic therapy for osteoporosis, measurement of serum 25-hydroxyvitamin D should follow three to four months of adequate supplementation and should not be repeated if an optimal level (≥ 75 nmol/L) is achieved. Vitamin D3 (cholecalciferol) is the preferred supplement as it is better absorbed than vitamin D2.

Question 59

Effectiveness of Calcium Supplements:

Answer 59

• Calcium supplements does produce a small positive effect on BMD in populations or
  patients with a lower calcium dietary intake.
• Calcium supplements alone does not reduce the risk of bone fractures.
• When treating osteoporosis, co-administration of calcium with anti-resorptive drugs has
  not been shown to impact on treatment efficacy.

Question 60

Effectiveness of Vitamin D Supplements:

Answer 60

• Vitamin D supplements does not improve BMD in clinical trials, except in subgroups with very low baseline levels of 25-hydroxyvitamin D.
• Correction of severe vitamin D deficiency (<25 nmol/L) with vitamin D supplements is necessary before use of potent anti-resorptive drugs to avoid hypocalcemia.
• Vitamin D supplements does slightly prevent fractures in populations with deficiency in vitamin D.

Question 61

Effectiveness of Combined Calcium and Vitamin D Supplementation:

Answer 61

• Calcium in combination with vitamin D supplementation has a positive effect on BMD.
• Calcium and vitamin D combined supplementation have been associated with only weak
  efficacy in reducing the risk of bone fractures in populations with already low calcium
  dietary intake.
• Supplementation with calcium and vitamin D does not prevent fractures in the general
  population.

Question 62

What are the harmful effects of Calcium?

Answer 62

• Excessive amounts or long-term use of calcium and vitamin D supplements can also cause calcium toxicity.
• Several studies and reviews have observed that long-term intake of calcium supplements commonly caused mild gastrointestinal side effects, particularly constipation, vomiting and nausea.
• Taking both calcium and vitamin supplements together does increase the risk of kidney stones.
• There is concern of potential adverse cardiovascular effects from calcium supplementation.
• Some calcium supplements can also interfere with iron and zinc absorption. For example, calcium carbonate can interfere with iron absorption from iron supplements. However, calcium citrate does not interfere with absorption of iron from iron supplements.

Question 63

Some calcium supplements can also interfere with iron and zinc absorption:

Answer 63

For example, calcium carbonate can interfere with iron absorption from iron supplements. However, calcium citrate does not interfere with absorption of iron from iron supplements.

Question 64

What are the harmful effects of Vitamin D?

Answer 64

Vitamin D is the vitamin most likely to have toxic effects when consumed in excess or after long-term usage.

Vitamin D supplementation:
Raises the concentrations of blood calcium, which tends to precipitate in soft tissues and forms stones, especially in the kidneys; causes calcification in blood vessels in the major arteries of the brain, heart, and lungs where it can cause death. Excess vitamin D intake can cause mild constipation, dizziness, and mental confusion, and can enhance bone resorption.

Question 65

In review of the current scientific evidence, it is reasonable to conclude that:

Answer 65

• Taken together, current evidence does not support beneficial effects of calcium supplements, vitamin D supplements, or calcium with vitamin D supplementation in the
  general population.
• Calcium supplements with or without vitamin D supplementation, at the very best, provide a very small effect of decreasing the risk of fractures osteoporotic patients.
• The issues of poor long-term compliance of calcium supplementation is related to mild
  but common gastrointestinal side effects
• Calcium and vitamin D supplements, or in combination, do not reduce the risk of fractures in healthy women and men in the general population without deficiency of either nutrients.