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