Diet and Health Guidelines to Lower Risk of Osteoporosis

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Diet and Health Guidelines to Lower
Risk of Osteoporosis
Presented by
Janice Hermann, PhD, RD/LD
OCES Adult and Older Adult Nutrition Specialist
What Is Osteoporosis
 Gradual reduction in bone mineral density,
causing bones to becomes thin and porous
 The fragile bones are at increased risk of
fracture
 Can fracture or break from a minor fall or
with normal everyday use
Symptoms
 Fractures (spine, hip, and wrist) most
common sites
 Loss of height
 Curved spine
 Because it progresses slowly, many people
don't realize they have osteoporosis until they
fracture a bone
Long Term Effects
 Affects millions in the United States
 Effects go beyond initial fracture
 Up to 25% with hip fractures die from
complications within a year
 Another 25% of people who survive never
return to their previous daily living ability
Good News
 Fracture risk related to osteoporosis can be
reduced by obtaining maximum bone mass
and bone density
 Diet, exercise and other lifestyle factors have
critical roles in maximizing bone mineral
density and lowering the risk of osteoporosis
and bone fractures
Understanding Bone
 There are two basic types of bone:
 Cortical
 Trabecular bone
 Both can lose minerals,
but different ways and
different rates
Cortical Bone
 Makes up the dense outer shell of bone
 Predominately found in the shafts of long
bones
 Has a slow turnover rate
Trabecular Bone
 Inner, lacy bone matrix, forms the bone's
internal support system
 Has a rapid turnover rate
 Found in flat bones, such as the vertebrae
and pelvis, and the ends of the long bones
Trabecular Bone
 Rapid turnover rate
 Releases calcium into blood, if dietary calcium
intake isn’t sufficient to maintain blood calcium
levels, and takes up calcium when dietary intake is
plentiful
 People who have eaten calcium-rich foods
throughout the bone-forming years of their youth
have dense trabecular bone which provides a
reservoir of calcium
Type Of Bone Loss
 In osteoporosis, loss of both types of bone
occurs
 Majority of loss is trabecular bone
Bone Loss
 Trabecular bone readily gives up calcium
whenever blood calcium levels are low
 Trabecular bone loss begins about age 30,
although loss can occur whenever calcium
withdrawal exceeds deposit
Bone Loss
 Cortical bone also gives up calcium, but at a
slow, steady pace
 Cortical bone loss typically begins at about
age 40 and continues slowly and steadily
thereafter
Bone Strength
 There are three major factors related to bone
strength:
 Bone mineral density
 Microfracture healing
 Trabecular integrity
Bone Mineral Density
 Bone fracture risk increases as bone mineral
density decreases
 Bone mineral density accounts for as much as
80 to 90% of bone strength
Microfracture Healing
 Increasing microfractures increase bone
fragility
 Bone remodeling and healing slow with age,
and microfractures thought to accumulate
Trabecular Integrity
 Integrity of trabecular bone, bone internal
support system, is an important aspect of
bone strength
 Thin or disconnected trabecular bone
increases the risk of bone fractures
Current Treatment Effects
 Current lifestyle treatments for osteoporosis
can preserve existing bone mineral density
 Current treatments cannot reconnect
trabecular bone or restore bone mineral
density to normal values
Types of Osteoporosis
 There are two main types of osteoporosis
 Type I Osteoporosis
 Type II Osteoporosis
 Primary and secondary osteoporosis
 Type I and Type II osteoporosis are termed primary
osteoporosis
 Secondary osteoporosis occurs secondary to
another disease condition
Type I Osteoporosis
Age Of Onset
Ratio Female:Male
Type Of Bone Loss
Fracture Sites
Main Causes
50-70
6:1
Trabecular
Wrist and Spine
Rapid loss of estrogen in
women following menopause;
Loss of testosterone in
men with advancing age
Type I Osteoporosis
 Involves rapid loss of trabecular bone
 Trabecular bone loss accelerates and bone breaks
may occur suddenly
 Trabecular bone becomes so fragile even body’s
weight can overburden spine
 Vertebrae may suddenly disintegrate and crush down,
painfully pinching nerves
Type II Osteoporosis
Age Of Onset
Ratio Female:Male
Type Of Bone Loss
Fracture Sites
Main Causes
Over 70
2:1
Trabecular & Cortical
Hip (due to both types of
bone loss over time)
Reduced calcium
absorption;
Increased bone mineral
loss;
Increased risk of falling
Type II Osteoporosis
 Involves loss of both cortical and trabecular
bone
 Losses occur slowly, over many years
 Vertebrae may compress into wedge
shapes forming what is often called
a “dowager’s hump”
Factors Affecting Bone Mineral Density
 Several factors affect bone density:
Non-Modifiable
Age
Gender
Family History
Genetics/Ethnicity
Modifiable
Calcium
Vitamin D
Other Nutrients
Physical Activity
Smoking
Alcohol
Body Weight
Age
 Two major life stages are critical in
development of osteoporosis
 First is the bone-acquiring stage of childhood and
adolescence
 Bones gain strength and density through growing years
and into young adulthood
 Second is the bone-losing decades of late
adulthood (especially in women after menopause)
Age
 Strongest factor associated with osteoporosis
 Risk increases with age
 Inefficient bone remodeling
 Decreased calcium intake
 Impaired vitamin D activation and status
 Impaired calcium absorption
 Decreased physical activity
 Hormonal changes favoring bone mineral loss
Age
 Age related factors contribute to bone loss
 Inefficient bone remodeling
 Cells that build bone gradually become less active, but
those that breakdown bone continue to work
 As a result bone loss exceeds bone formation
 Decreased calcium intake
 Lactose tolerance tends to decrease with age
Age
 Age related factors contribute to bone loss
 Impaired vitamin D activation and status
 Many older adults spend less time outdoors in the
sunshine resulting in decreased vitamin D formation
 Decreased kidney activation of vitamin D
 Since vitamin D is needed to absorb calcium, decreased
vitamin D formation and activation results in decreased
calcium absorption
Age
 Age related factors contribute to bone loss
 Decreased physical activity
 Hormonal changes favoring bone mineral loss
 Some hormones (parathormone, calcitonin, and
estrogen) that regulate bone and calcium metabolism
change with age and accelerate bone mineral withdrawal
Gender
 Second strongest factor associated with
osteoporosis
 Occurs more in females than males
 Lower bone mass density
 Lower calcium intake
 Lose trabecular bone at a greater rate
 Lose hormone estrogen, that helps deposit
calcium in bones
Gender
 Menopause particularly impacts women
 Estrogen helps deposit calcium in bones
 Loss of bone mass rapidly increases during the six
to eight years following menopause, due to the
loss of estrogen
 Women may lose up to 20 % of bone mass during the six
to eight years following menopause
 Eventually, rate of bone loss decreases until
women lose bone at a similar rate as men their age
Gender
 Rapid bone losses also occur when young
women’s ovaries fail to produce enough
estrogen, causing menstruation to cease
 Ovaries may be diseased and must be removed
 Anorexia nervosa can result in low body weight
which can cause the ovaries to fail to produce
enough estrogen resulting in amenorrhea
Gender
 Estrogen therapy:
 Can prevent further bone loss and reduce fractures
 However, estrogen therapy may increase heart disease
and breast cancer risk
 Women must carefully discuss potential benefits and
dangers with their physician
 Other prescription medications are available
to prevent or treat osteoporosis
 Medications work by inhibiting bone-breakdown
cells, thus allowing bone-building cells to build up
bone tissue with new calcium deposits
Gender
 Soy
 Phytochemicals commonly found in soybeans
mimic estrogen action and stimulate estrogensensitive tissues
 As a result, phytochemicals in soy may help to prevent
post-menopausal bone loss
 However, research is far from conclusive
 Some research suggests soy may offer some
protection
 However, supplements of isolated soy extracts may
actually increase cancer risk
Gender
 If estrogen deficiency is a major cause of
osteoporosis in women, what is the cause of
bone loss in men?
 Male hormone testosterone appears to play a
role
 Low levels of testosterone, as occurs after
removal of diseased testes or when testes lose
function with aging, results in more fractures
Family History
 Family history of osteoporosis is a risk factor
Genetics and Ethnicity
 Exact role of genetics is unclear, but most
likely it influences:
 Peak bone mass achieved during growth
 Bone loss incurred during the later years
Genetics and Ethnicity
 Racial differences in osteoporosis may reflect
genetic differences in bone development
 African Americans have greater bone density and a
lower rate of osteoporosis than Caucasians
 African Americans seem to use and conserve calcium
more efficiently than Caucasians
 Fractures are twice as likely in Caucasian women 65
years or older than African American women
Genetics and Ethnicity
 Other ethnic groups have a high risk of
osteoporosis
 Asians from China and Japan, Mexican Americans,
Hispanic people from Central and South American,
and Inuit people from St. Lawrence Island typically
have lower bone density than Caucasians
 Would expect these groups would suffer more
bone fractures, but this is not always the case
 May be explained by genetic, dietary , physical activity
and other lifestyle differences
Genetics and Ethnicity
 Although genetics may lay the groundwork,
other factors influence the genes’ ultimate
expression
 Diet in general, calcium and vitamin D in
particular
 Others include physical activity, smoking, alcohol
and body weight
Calcium
 99% of calcium in bones and teeth
 1% of body calcium circulates in blood
Regulate heart beat
Relax muscles
Transmit nerve impulses
Blood coagulation
Component of enzymes
Acid-base balance
Maintain blood pressure
Why Need Calcium Daily
 Maintaining blood calcium
 Although calcium in blood is small, it is very
important
 If dietary calcium inadequate to maintain 1 %
blood calcium, calcium pulled from the bones
 Maintaining blood calcium is one reason calcium
in the diet is needed every day
Why Need Calcium Daily
 Bone remodeling
 Bones are not static, they constantly being
remodeled
 Calcium is continuously being removed from bone
and new calcium deposited
 600 to 700 mg calcium deposited each day in
newly forming adult bones
Bone Formation
 Body deposits greatest amounts of calcium
during growth years to add length and
diameter to growing bones
 After about age 20, body deposits calcium to
increase bone density rather than to increase
the length or diameter
Bone Formation
 After about age of 30, all individuals,
especially women, lose bone mass at a
faster rate than it is reformed
 Maximizing peak bone mass in early years
helps lower risk of osteoporosis in later life
 Have more bone to start with so able to lose
more bone before suffering ill effects
Calcium Intake
 Many Americans do not consume enough
calcium
 Women and teenage girls especially fall short
of an adequate calcium intake
 Teenage and young women who do not get
enough calcium, do not maximize their peak
bone density and may be at higher risk of
osteoporosis
How Much Calcium
 Recommended Dietary Allowance
 Men (19-70 yr): 1,000 mg/day
 Men (71+ yr): 1,200 mg/day
 Women (19-50 yr): 1,000 mg/day
 Women (51+ yr): 1,200 mg/day
 Upper Level
 Adults (19-50 yr): 2,500 mg/day
 Adults (51+ yr): 2,000 mg/day
Sources Of Calcium
 Dairy foods main dietary calcium source
 These foods also contain other nutrients, such
as vitamin D, that help body absorb calcium
 If dairy foods omitted from the diet it is
difficult to consume adequate amounts of
calcium
Other Calcium Sources
 Salmon & sardines with eatable bones
 Tofu processed with calcium sulfate
 Dark green leafy vegetables, such as broccoli,
collards, kale, mustard greens and turnip
greens
 Foods such as orange juice and breakfast
cereals fortified with calcium
Calcium Supplements
 For those unable to consume enough
calcium-rich foods, taking calcium
supplements may be appropriate
 Selecting a supplement takes some
evaluation
 Many multivitamin-mineral supplements
contain little or no calcium
Calcium Supplements
 Single nutrient calcium supplements are
typically sold as compounds of:
 Calcium carbonate
 Calcium citrate
 Calcium gluconate
 Calcium lactate
 Calcium malate
 Calcium phosphate
 Calcium supplements often include vitamin D,
magnesium, or both
Calcium Supplements
 Calcium supplements made from:
 Bone meal
 Oyster shell
 Dolomite (limestone)
are not recommended because they may
contain heavy metals, such as lead – which
impairs health in numerous ways
Calcium Supplements
 Determine how much calcium the
supplement provides
 Most calcium supplements provide between 250
and 1,000 milligrams of calcium
 To be safe, total calcium intake from both foods
and supplements should not exceed the upper
level:
 Adults (19-50 yr): 2,500 mg/day
 Adults (51+ yr): 2,000 mg/day
Calcium Supplements
 Better to take a low-dose supplement
several times a day rather than a large-dose
supplement all at once
 Taking calcium supplements in doses of 500
milligrams or less improves absorption
 Small doses also help ease the GI distress
(constipation, intestinal bloating, and excessive
gas) that sometimes accompanies calcium
supplement use
Calcium Supplements
 Most healthy people absorbs and use
calcium equally well from various
supplements
 Calcium citrate is an acid form which may help
with absorption for older adults with
achlorhidria (low stomach acidity)
 Consuming a supplement with a source of
vitamin C can help with absorption
Calcium Supplements
 When to take a supplement
 Calcium from supplements are better absorbed
when taken with meals
 Try to avoid taking calcium supplements with iron
supplements or iron rich meals; calcium inhibits
iron absorption
Calcium Supplements
 Supplement disintegration
 When manufacturers compress large quantities
of calcium into small pills, the stomach acid has
difficulty penetrating the pill
 To test a supplement’s ability to dissolve, drop
into a 6-ounce cup of vinegar, and stir
occasionally
 A high-quality formulation will dissolve within
half an hour
Calcium Supplements
 However, before just automatically
depending on a supplement, people should
reconsider the benefits of food sources of
calcium
 Foods are the best sources of calcium
 Foods supply other nutrients bones need in
addition to calcium
 Supplements should “supplement” not
“replace” the diet
Vitamin D
 Vitamin D helps absorb and deposit calcium
and phosphorous in the bones
 The body can make vitamin D when the skin is
exposed to sunlight
 Sunscreens help reduce the risk of skin
cancer, but sunscreens with a protection
factor of 8 and above also prevent vitamin D
synthesis
How Much Vitamin D
 Recommended Dietary Allowance
 600 IU/day (Adults 19-50 yr)
 600 IU/day (Adults 51-70 yr)
 800 IU/day (Adults 71 + yr)
 Upper Level
 Adults: 4,000 IU/day
Sources of Vitamin D
 Milk is an excellent source of vitamin D
because fluid milk is fortified with vitamin D
 Cheese, eggs, some fish (sardines and
salmon)
 Fortified cereals and margarine also contain
small amounts of vitamin D
Older Adults Lower Intake
 Older adults at greater risk for low vitamin D
intake
 Limited sunlight exposure, resulting in lower
vitamin D formation
 Kidneys less efficient at converting vitamin D into
active form
 Lower intake of dairy foods, which contain vitamin
D, if have a problem with lactose intolerance
Other Nutrients
 Many nutrients have critical roles in bone
formation and maintenance
 Protein
 Vitamins: D, C, B12, K, and folate
 Minerals: calcium, phosphorous, zinc, copper,
magnesium, iron, fluoride & boron
 Importance of these nutrients can’t be
ignored in the enthusiasm for calcium and
vitamin D
Some Excesses Not Good
 Excessive protein, especially sulfur-containing
amino acids, and high sodium may increase
calcium excretion
 Whether this effects bone development remains
unclear
 Excessive alcohol increases calcium excretion
and decreases bone formation
Physical Activity
 Weight bearing physical activity
 Places mechanical stress, particularly on the ends
of the long bones, which stimulates bone
remodeling and increases bone formation, making
them stronger and denser
 Strengthens muscles that in turn pull or tug on
bones, which also keeps bones strong
 Improves coordination, thus reducing the risk of
falls and bone injuries
Physical Activity
 Weight bearing physical activity can be
beneficial at various age groups
 Maximize bone density in adolescence
 Maintain bone density in adults
 Even past menopause when most women are
losing bone, weight training improves bone density
Physical Activity
 To keep bones healthy, a person should
engage in weight bearing activities daily
 Benefits of weight bearing physical activities
are site-specific, bones used in physical
activity are strengthened
 Include a variety of weight bearing physical
activities such as walking, jogging, running,
tennis, weight lifting, aerobics and dancing
Smoking
 Smoking increases the risk of osteoporosis
 Shown to lower bone mineral density
 Promotes a condition called acidosis, which
stimulates bone loss
 Lowers estrogen levels, in women, further
contributing to bone loss
Alcohol
 Alcohol in moderate amounts may protect
bone density by decreasing remodeling
activity; however
 People who abuse alcohol often suffer from
osteoporosis and experience more fractures
Alcohol
 Abusive alcohol use increases the risk of
osteoporosis
 Increases fluid loss which can lead to excessive
calcium loss in urine
 Upsets hormone balance for healthy bones
 Slows bone formation
 Stimulates bone breakdown
 Increases risk of falling
Body Weight
 Heavier body weight places mechanical stress
on the bones and promotes bone density
 Newer research is showing differences between
weight from lean muscle and fat
 Weight from lean muscle has beneficial bone effects
 Excessive weight from fat, obesity, may increase bone loss
 Underweight and excessive weight loss are
significant predictors of bone loss and fracture
risk
Lowering Risk of Osteoporosis
 Adequate calcium and vitamin D
 Consume recommended amount of foods
from the USDA Daily Food Plan food groups to
get the variety of nutrients in addition to
calcium and vitamin for bone health
 Regular weight-bearing physical activity
 Moderation in alcohol, protein and sodium
 Not smoking
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