Michael GunawanMichael Gunawan

030.06.116030.06.116

• Osteoporosis → Skeletal disorder characterized by decrease bone

mass and deterioration of bony microarchitecture.

• It is a multifactorial disorder in which nutrition plays role but does

not account for the totality of the problem.

• The result: Fragile bones and risk for fracture.

• BMD is reduced, bone microarchitecture is disrupted, and the

amount and variety of non-collagenous proteins in bone is altered.

• Many papers → describe studies of relationship of calcium intake and

bone health

• 52 investigator-controlled calcium intervention studies → two showed

better bone balance at high intakes, greater bone gain during growth,

reduced bone loss in the eldery, or reduced fracture risk.

• High calcium intakes → bone health.

• Most studies: based on dairy calcium.

• Higher calcium = higher dairy intakes → Connection between dairy

foods and bone health.

BACKGROUND

• Osteoporosis → Skeletal fragility → Characterized by

decreased bone mass and microarchitectural deterioration of

bone tissue → Increase risk of fracture.

• Fracture: In the form of cracking (as in a hip fracture), or

collapsing (as in a compression fracture of the vertebrae of the

spine).

• Spine, hips, and wrists are common areas of osteoporosis-

related bone fractures.

• Nutrition (calcium) plays an important role in protecting

against osteoporosis → development and maintenance of

bone mass and by maintaining normal postural reflexes

and soft tissue mass.

• Human needs calcium to stay healthy changes over

lifetime.

• Body's demand for calcium → greatest during childhood

and adolescence, during pregnancy and breast-feeding.

• Osteoporosis is a condition that features loss of the normal density

of bone and fragile bone.

• Normal bone: protein, collagen, and calcium.

• Bones that are affected by osteoporosis can fracture with only a

minor fall or injury.

• The fracture can be either in the form of cracking (hip fracture), or

collapsing (compression fracture of vertebrae).

• Spine, hips, and wrists: common areas.

• Etiological factors of primary osteoporosis → Family history

of fracture or low bone mass.

• Heritability of fracture as well as low BMD: 25-80%.

• Menopause → correlated with a rapid reduction in BMD →

Leads to fractures of the wrist, spine and hip.

• Hormone deficiency: testosterone, glucocorticoid or thyroxine,

and calcium and/or vitamin D deficiency → Increase risk of

osteoporosis.

• Underlying mechanism: imbalance bone resorption and

bone formation → Bone resorption is excessive, bone

formation is diminished.

• Bone matrix: osteoblast cells.

• Bone resorption: osteoclast cells.

• Bone remodeling → Influenced by nutritional and

hormonal factors.

• Calcium and vitamin: Required for normal bone growth.

• Parathyroid hormone → regulates composition of bone.

• Glucocorticoid hormones → Increase osteoclast.

• Calcitonin and estrogen → Increase osteoblast.

• Estrogen following menopause causes a phase of rapid

bone loss.

• Testosterone in men: Related to male osteoporosis.

• Dual energy X-ray absorptiometry (DXA): Gold standard.

• Diagnosis → BMD is less than or equal to 2.5 standard

deviations (T - Score).

WHO: Criteria for the Diagnosis of Osteoporosis (1)

CATEGORY CRITERIA (EXPRESSED AS T - SCORE)

NormalPatient BMD 1 SD of average peak young adult BMD (T-score, 0 to -1)

Osteopenia Patient BMD between 1 SD and 2.5 SD below average peak young adult BMD (T-score, -1 to -2.5)

Osteoporosis Patient BMD 2.5 SD below average peak young adult BMD (T-score, -2.5)

Severe Osteoporosis

Patient BMD 2.5 SD below average peak young adult BMD with fragility fractures

• Fractures: most frequent and serious complication.

• It often occur in your spine or hips — bones that directly

support your weight.

• Hip fractures: second most common type of osteoporotic

fracture → result from a fall.

• Hip fractures → disability and edeath from postoperative

complications.

• Wrist fractures from falls also are common.

• Spinal fractures can occur without any fall or injury

simply because vertebrae become so weakened that they

begin to compress.

• Compression fractures → severe pain and require a long

recovery.

Clinical risk factors for osteoporosis(4).• Previous vertebral fracture or low trauma appendicular

fracture• Post-menopausal woman not receiving HRT• Premature menopause at <45 year or male hypogonadism• Age > 65 year• Planned or current CS use of > 6 months• Low BMI: < 20 kgum2• History of low trauma maternal hip fracture at < 60 year• Other causes of osteoporosis, e.g. alcohol excess, RA,• Hyperparathyroidism, thyrotoxicosis

• Bone is living tissue → have same kinds of nutrient needs

of the body: for energy supply, protein and micronutrients.

• Bone growth → stunted ingeneral malnutrition bony and

abnormalities develop with deficiencies of protein, ascorbic

acid, vitamin D, magnesium, zinc, copper and manganese.

• Bone depends upon dietary intake → supply the bulk

materials → synthesis of the extracellular material:

composes > 95% of the substance of bone.

• Bulk materials: calcium, phosphorus and protein.

• Extracellular material of bone: protein and calcium

phosphate crystals.

• Calcium is lost through shed skin, hair, nails, sweat, urine

and digestive secretions (range 4-8 mmol) → depending

physical activity and dietary constituents.

• Absorbed calcium input in an adult fails to match daily

losses → blood calcium levels begin to fall → increased

secretion of parathyroid hormone (PTH): resorbs bone

and releases into blood.

• This is relationship between low calcium intake and low

bone mass → respect to failure to achieve the genetically

programmed peak mass (calcium intake is inadequate),

and respect to losses of bone after maturity (ingested

calcium is not sufficient to offset daily loss from body).

FIGURE.. Plots of the cumulative incidence of fractures, redrawn from the studies of Chapuy et al (17) (right) and Dawson-Hughes et al (18) (left). In both cases, the upper line represents the placebo control subjects and the lower line represents the subjects treated with calcium and vitamin D. The shaded zones represent the reduction of fracture risk, which, as can be readily seen, starts with the beginning of treatment

• Fifty-two of these studies consisted of investigator controlled

interventions: 37 in adults, 14 in children or adolescents and 1

combining both age groups.

• All of the metabolic and physiologic studies showed that higher

calcium intakes produced better calcium retention or reduced bone

remodeling.

• Two of these metabolic balance studies used dairy products as the

calcium source.

• Several of the balance studies used dose-ranging

approaches to estimate the average requirement for

maximal retention during adolescence and for zero

balance during maturity.

• Results were in the range of 35 to 40 mmol/d for growth

and varied from 22 to 40 mmol/d for mature adults.

• Even the low ends of these ranges are substantially above

both typical intakes today and the 1989 RDAs

• All but two of the randomized, controlled trials (RCTs) in

adults showed that elevating calcium intake reduced or

halted age-related bone loss or reduced osteoporotic

fractures at one or another bony site, or both.

• In one of the trials failing to find a benefit of increased

calcium intake, the study consisted of only 77 healthy men

in whom the mean calcium intake of the control group was

1159 mg, already relatively high.

• In the other, the subjects were early postmenopausal

women, a group in whom bone loss is predominantly

related to estrogen withdrawal, not to nutrition.

• Six controlled trials used dairy products as the calcium

source, and all were positive

• Six of the randomized controlled trials in adults and children

used dairy products as the principal source of calcium.

• All showed significantly positive effects that were at least as

strong as the effects of calcium supplements.

• It is evident that milk and milk products are good sources of

the nutrients needed for bone development and maintenance.

• Many population groups, particularly adolescent and

older females and older adults, consume diets

containing significantly less calcium than

recommended.

• At all ages, males consume more calcium than

females, presumably because of their higher energy

intake.

•Data from the Continuing Survey of Food Intakes by Individuals

(CSFII) 1994–96 indicate that only 12% of females ages 12 to 19 and

32% of similar aged males are meeting 100% of the AI (Adequate

Intakes) for calcium.

•According to this same survey, only 16% of women ages 20 to 29

years, 14% of women ages 30 to 39 years, and 11.5% of women 40

to 49 years are meeting 100% of the AI for calcium.

•Although less than 15% of older adults are consuming 100% of the

calcium AI, more men than women are meeting calcium

recommendations.

• Approximately 15% of males aged 50 to 59, 13% of males aged

60 to 69, and 13% of males over 70 years consume 100% of the

calcium recommendations. In contrast, only 5% of women ages

50 to 59, 4% of women aged 60 to 69, and 4% of women ages 70

and older consume 100% of the calcium recommendation.

• The low dietary calcium intake of adolescents is of particular

concern because it coincides with a period of rapid skeletal

growth—a "window of opportunity" to maximize peak bone

mass and protect against future risk for osteoporosis.

• About 90% of females’ total body bone mineral

content is achieved by age 16.9 years, 95% by age

19.8 years, and 99% by age 26.2 years, depending

on the site measured.

• Consequently, the period for optimizing peak bone

mass by calcium rapidly declines after

adolescence.

FIGURE... Percentage of Individuals Meeting 100 Percent of the 1997 AIs for

Calcium by Gender and Age, Two-Day Average 1994–1996

• Not only are milk and other dairy foods calcium-dense foods

providing in many cases about 300 mg calcium per serving, but

these foods also contain other nutrients important to health.

• Milk and other dairy foods contain → vitamins D, A, and B12,

protein, potassium, riboflavin, niacin, and phosphorus.

• Vitamin D-fortified milk products provide dietary intake of

vitamin D → increases the absorption of calcium.

NUTRIENT 1997%

Energy 9.3

Protein 19.4

Fat 12.6

Carbohydrate 4.6

Minerals

Calcium 72.1

Phosphorus 32.4

Zinc 16.2

Magnesium 15.8

Iron 1.8

Vitamins

Riboflavin 26.1

Vitamin B 12 21.6

Vitamin A 15. 3

Vitamin B 6 8.7

Folate 6.2

Thiamin 4.7

Vitamin E 2.8

Ascorbic Acid 2.5

Niacin 1.2

• Because milk and other dairy foods are excellent sources of calcium as

well as many other essential nutrient, their intake improves the overall

nutritional quality of the diet.

• A longitudinal study involving 64 postmenopausal women in Australia

found that the women who were randomly assigned to receive 1,000

mg of additional calcium per day by consuming fat free milk powder

increased not only their calcium intake, but also their intake of other

essential nutrients such as protein, potassium, phosphorus, magnesium,

riboflavin, thiamin and zinc.

• Women who took calcium supplements (calcium lactate

gluconate) increased only their intake of calcium and

sodium.

• Although both milk powder and calcium supplements

increased calcium intake, consuming the fat free skim milk

powder improved the women’s total diet as well.

• The total nutrient content of milk is also well understood,

and it is almost unnecessary to state here that milk

products are richer sources of calcium, phosphorus,

magnesium, potassium, zinc and protein, per unit energy,

than the average of other typical foods in an adult diet.

• As a consequence, a diet devoid of dairy products will

often be a poor diet, not just in respect to calcium, but for

many other nutrients as well.

FIGURE... Calcium Contribution of Foods(3)

• Consuming calcium-rich foods is the preferred approach to achieving

optimal calcium intakes.

• Dairy foods: major source of calcium → other essential nutrients,

including vitamin D, which increases calcium absorption.

• Consuming dairy foods improves the overall nutritional quality of the

diet.

• Nondairy foods: salmon with bones, green leafy vegetables and

legumes also provide calcium.

• Calcium-fortified foods and calcium supplements: option for

individuals who cannot meet their calcium needs from foods naturally

containing this mineral.

• Their use does not correct the poor dietary patterns of food selection

which are the underlying cause low calcium consumption.

• Intake of calcium-fortified foods and calcium supplements may

increase the risk for calcium toxicity, especially among individuals

who already meet their calcium needs from foods naturally

containing this mineral.

1. Heaney RP. Calcium, Dairy Products and Osteoporosis. Journal of the American College of Nutrition 2000; 19: 83S-99S.

2. Heaney RP. Bone Health. American Journal of Clinical Nutrition 1997; 85: 300S-303S.

3. Miller GD, Jarvis JK, McBean LD. The Importance of Meeting Calcium Needs with Foods. Journal of the American College of Nutrition 2001; 20: 168S-185S

4. Yeap SS, Hosking DJ. Management of Corticosteroid - Induced Osteoporosis. Rheumatology 2002; 41: 1088–1094

5. Reid IR, Ames RW, Evans MC, Gamble GD, Sharpe SJ. Effect of Calcium Supplementation on Bone Loss in Postmenopausal Women. N Engl J Med 1993; 328: 460–464.

6. Cumming RG, Cummings SR, Nevitt MC, Scott J, Ensrud KE, Vogt TM, Fox K: Calcium Intake and Fracture Risk: Results from The Study of Osteoporotic Fractures. Am J Epidemiol 1997; 145: 926–934.

7. Chapuy MC, Arlot ME, Duboeuf F, et al. Vitamin D3 and Calcium to Prevent Hip Fractures in Elderly Women. N Engl J Med 1992; 327: 1637–42.

8. Suleiman S, Nelson M, Li F, Buxton-Thomas M, Moniz C: Effect of Calcium Intake and Physical Activity Level on Bone Mass and Turnover in Healthy, White, Postmenopausal Women. Am J Clin Nutr 1997; 66: 937–943.