RESUMEN
PURPOSE: Oral bone and tooth loss are correlated with bone loss at nonoral sites. Calcium and vitamin D supplementation slow the rate of bone loss from various skeletal sites, but it is not known if intake of these nutrients affects oral bone and, in turn, tooth retention. SUBJECTS AND METHODS: Tooth loss was examined in 145 healthy subjects aged 65 years and older who completed a 3-year, randomized, placebo-controlled trial of the effect of calcium and vitamin D supplementation on bone loss from the hip, as well as a 2-year follow-up study after discontinuation of study supplements. Teeth were counted at 18 months and 5 years. A comprehensive oral examination at 5 years included assessment of caries, oral hygiene, and periodontal disease. The odds ratio (OR) and 95% confidence interval (CI) of tooth loss were estimated by stepwise multivariate logistic regression. Initial age (mean +/- SD) of subjects was 71 +/- 5 years, and the number of teeth remaining was 22 +/- 7. RESULTS: During the randomized trial, 11 of the 82 subjects (13%) taking supplements and 17 of the 63 subjects (27%) taking placebo lost one or more teeth (OR = 0.4; 95% CI: 0.2 to 0.9). During the 2-year follow-up period, 31 of the 77 subjects (40%) with total calcium intake of at least 1000 mg per day lost one or more teeth compared with 40 of the 68 subjects (59%) who consumed less (OR = 0.5; 95% CI: 0.2 to 0.9). CONCLUSION: These findings suggest that intake levels of calcium and vitamin D aimed at preventing osteoporosis have a beneficial effect on tooth retention.
Asunto(s)
Calcio de la Dieta/uso terapéutico , Colecalciferol/uso terapéutico , Ácido Cítrico/uso terapéutico , Suplementos Dietéticos , Malatos/uso terapéutico , Osteoporosis/prevención & control , Pérdida de Diente/prevención & control , Anciano , Densidad Ósea/efectos de los fármacos , Calcio , Método Doble Ciego , Femenino , Cuello Femoral/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Masculino , Oportunidad Relativa , Salud Bucal , Higiene Bucal , Radiografía , Diente/efectos de los fármacosRESUMEN
Osteoporosis and osteopenia may influence periodontal disease and tooth loss. Medications such as hormone replacement therapy and nutritional supplements that are used to prevent or treat osteoporosis have been evaluated for beneficial effects on oral health in a small number of human studies. Hormone replacement therapy (HRT), which slows the rate of bone loss at skeletal sites such as the hip and spine, also appears to reduce the rate of alveolar bone loss in postmenopausal women. HRT use is consistently associated with greater tooth retention and a reduced likelihood of edentulism in studies of elderly women. The number of studies on the effects of calcium or vitamin D intake on oral outcomes is limited, but suggest that higher intake levels are associated with reduced prevalence of clinical attachment loss and lower risk of tooth loss. Data from a prospective study of oral health in men show a similar association between higher calcium intake and reduced alveolar bone loss. The number of teeth with progression of alveolar bone loss over a 7-year period was significantly lower among men whose calcium intake was at least 1,000 mg per day, compared to men with a calcium intake below this level. Future studies should confirm these findings and evaluate the oral effects of new medications for osteoporosis. If confirmed, the implications for dental professionals may include an expanded array of medications for the treatment of periodontal disease and a greater emphasis on nutrition education for patients.
Asunto(s)
Pérdida de Hueso Alveolar/fisiopatología , Osteoporosis/fisiopatología , Anciano , Pérdida de Hueso Alveolar/prevención & control , Pérdida de Hueso Alveolar/terapia , Análisis de Varianza , Calcio de la Dieta/administración & dosificación , Distribución de Chi-Cuadrado , Suplementos Dietéticos , Progresión de la Enfermedad , Conducta Alimentaria , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Ciencias de la Nutrición/educación , Osteoporosis/terapia , Índice Periodontal , Estudios Prospectivos , Fumar , Estadística como Asunto , Vitamina D/administración & dosificaciónRESUMEN
BACKGROUND: Supplementation with calcium and vitamin D reduces bone loss and prevents fractures in elderly people, but it is not known whether any lasting benefit remains if the supplements are discontinued. OBJECTIVE: The objective was to determine whether gains in bone mineral density (BMD) induced by calcium and vitamin D supplementation persist after supplement withdrawal. DESIGN: Two-hundred ninety-five healthy, elderly men and women (aged >/=68 y) who had completed a 3-y randomized, placebo-controlled trial of calcium and vitamin D supplementation were followed for an additional 2 y during which no study supplements were given. BMD was measured by dual-energy X-ray absorptiometry, and biochemical variables related to calcium metabolism and bone turnover were measured. RESULTS: In the 128 men, supplement-induced increases in spinal and femoral neck BMD were lost within 2 y of supplement discontinuation, but small benefits in total-body BMD remained. In the 167 women, there were no lasting benefits in total-body BMD or at any bone site. Consistent with the observations on BMD, the bone turnover rates in both men and women (as measured by serum osteocalcin concentrations) returned to their original higher concentrations within the same 2-y period. CONCLUSION: Discontinued calcium and vitamin D supplementation has limited cumulative effect on bone mass in men and women aged >/=68 y.
Asunto(s)
Densidad Ósea/efectos de los fármacos , Calcio/administración & dosificación , Vitamina D/administración & dosificación , Absorciometría de Fotón , Anciano , Remodelación Ósea , Calcio/uso terapéutico , Femenino , Cuello Femoral/efectos de los fármacos , Estudios de Seguimiento , Fracturas Óseas/prevención & control , Humanos , Masculino , Concentración Osmolar , Osteocalcina/sangre , Columna Vertebral/efectos de los fármacos , Vitamina D/uso terapéuticoRESUMEN
Cigarette use is a risk factor for increased bone mineral density (BMD) loss but the mechanisms are not well understood. The relationship of smoking to rates of BMD change at the femoral neck, spine, and total body, and to intestinal calcium absorption were examined in 402 elderly men and women (32 smokers, 370 nonsmokers) who participated in a 3-year placebo-controlled study of calcium and vitamin D supplementation. Subjects in the supplemented group took 500 mg/day of elemental calcium and 700 IU/day of cholecalciferol. Two-hour calcium absorption fraction was determined three times, at 18, 30, and 36 months, with a single isotope method utilizing 45Ca in a subset of 333 subjects. Annualized rates of BMD loss (adjusted for baseline BMD, weight, age, gender, supplementation status, and dietary calcium intake) were higher in smokers than nonsmokers at the femoral neck (-0.714 +/- 0.285 %/year vs. +0.038 +/- 0.084 %/year, p < 0.02), and total body (-0.360 +/- 0.101 %/year vs. -0. 152 +/- 0.030 %/year, p < 0.05). No significant difference was observed at the spine (+0.260 +/- 0.252 %/year in smokers vs. +0.593 +/- 0.074 %/year in nonsmokers, p = 0.21). The mean (+/- SEM) calcium absorption fraction was lower in smokers (12.9 +/- 0.8%, n = 23) than nonsmokers (14.6 +/- 0.2%, n = 310, p < 0.05) after adjustment for gender, age, supplementation status, and dietary calcium and vitamin D intakes. Smokers of at least 20 cigarettes per day (n = 15) had the lowest mean absorption fraction (12.1 +/- 1.1%). With calcium and vitamin D supplementation, the proportionate increase in urinary calcium/creatinine excretion was lower in smokers (44 +/- 12%) than nonsmokers (79 +/- 9%, p < 0.05). These results suggest that smoking accelerates bone loss from the femoral neck and total body in the elderly and that less efficient calcium absorption may be one contributing factor.
Asunto(s)
Calcio de la Dieta/farmacocinética , Absorción Intestinal , Osteoporosis/etiología , Fumar/efectos adversos , Fumar/metabolismo , Anciano , Densidad Ósea/efectos de los fármacos , Calcio/orina , Calcio de la Dieta/administración & dosificación , Creatinina/orina , Femenino , Humanos , Masculino , Osteoporosis/tratamiento farmacológico , Osteoporosis/metabolismo , Factores de Riesgo , Vitamina D/administración & dosificaciónRESUMEN
BACKGROUND: Inadequate dietary intake of calcium and vitamin D may contribute to the high prevalence of osteoporosis among older persons. METHODS: We studied the effects of three years of dietary supplementation with calcium and vitamin D on bone mineral density, biochemical measures of bone metabolism, and the incidence of nonvertebral fractures in 176 men and 213 women 65 years of age or older who were living at home. They received either 500 mg of calcium plus 700 IU of vitamin D3 (cholecalciferol) per day or placebo. Bone mineral density was measured by dual-energy x-ray absorptiometry, blood and urine were analyzed every six months, and cases of nonvertebral fracture were ascertained by means of interviews and verified with use of hospital records. RESULTS: The mean (+/-SD) changes in bone mineral density in the calcium-vitamin D and placebo groups were as follows: femoral neck, +0.50+/-4.80 and -0.70+/-5.03 percent, respectively (P=0.02); spine,+2.12+/-4.06 and +1.22+/-4.25 percent (P=0.04); and total body, +0.06+/-1.83 and -1.09+/-1.71 percent (P<0.001). The difference between the calcium-vitamin D and placebo groups was significant at all skeletal sites after one year, but it was significant only for total-body bone mineral density in the second and third years. Of 37 subjects who had nonvertebral fractures, 26 were in the placebo group and 11 were in the calcium-vitamin D group (P=0.02). CONCLUSIONS: In men and women 65 years of age or older who are living in the community, dietary supplementation with calcium and vitamin D moderately reduced bone loss measured in the femoral neck, spine, and total body over the three-year study period and reduced the incidence of nonvertebral fractures.
Asunto(s)
Densidad Ósea/efectos de los fármacos , Calcio/uso terapéutico , Ácido Cítrico/uso terapéutico , Fracturas Óseas/prevención & control , Malatos/uso terapéutico , Vitamina D/uso terapéutico , Anciano , Calcio/sangre , Calcio/farmacología , Ácido Cítrico/farmacología , Colágeno/orina , Colágeno Tipo I , Método Doble Ciego , Femenino , Cuello Femoral/efectos de los fármacos , Fracturas Óseas/epidemiología , Humanos , Incidencia , Malatos/farmacología , Masculino , Osteocalcina/sangre , Péptidos/orina , Riesgo , Columna Vertebral/efectos de los fármacos , Vitamina D/sangre , Vitamina D/farmacologíaRESUMEN
A genetic marker for the 1,25-dihydroxyvitamin D receptor (VDR) is reported to account for much of the heritable component of bone density. It is not known whether VDR genotype influences bone accretion or loss, or how it is related to calcium metabolism. The VDR genotype was determined in 229 healthy postmenopausal women who previously participated in a calcium trial. VDR alleles were designated according to presence (b) or absence (B) of the BsmI restriction enzyme cutting site. There were 83 bb, 102 Bb, and 44 BB individuals. Two-thirds of the women took 500 mg of calcium supplement (mean calcium intake = 892 mg/day) and one-third a placebo (mean = 376 mg/day). Bone mineral density (BMD) at the femoral neck, spine, and radius were measured by dual- and single-photon absorptiometry at baseline and after 1 and 2 years. Among women more than 10 years postmenopausal, those with the BB genotype had the lowest femoral neck BMD. Rates of bone loss over 2 years were greater in the BB group at all sites (e.g., at the femoral neck, bb, 0.45 +/- 0.43; Bb, -0.01 +/- 0.40; BB, -0.99 +/- 0.50%/year; BB vs. bb, p = 0.01), and this trend was found both in women < 10 years since menopause (e.g., at the radius, bb, 0.43 +/- 0.47; Bb, -0.37 +/- 0.42; BB, -1.20 +/- 0.59% per year; BB vs. bb, p = 0.02) and those > or = 10 years (radius, bb, -0.71 +/- 0.41; Bb, 0.08 +/- 0.39; BB, -1.41 +/- 0.49% per year; BB vs. Bb, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Envejecimiento/fisiología , Densidad Ósea/genética , Calcio de la Dieta/administración & dosificación , Osteoporosis Posmenopáusica/genética , Receptores de Calcitriol/genética , Absorciometría de Fotón , Anciano , Alelos , Secuencia de Bases , Densidad Ósea/fisiología , Calcio de la Dieta/uso terapéutico , Estudios de Cohortes , Cartilla de ADN/química , Femenino , Cuello Femoral/fisiología , Genotipo , Humanos , Estudios Longitudinales , Vértebras Lumbares/fisiología , Persona de Mediana Edad , Datos de Secuencia Molecular , Osteoporosis Posmenopáusica/fisiopatología , Osteoporosis Posmenopáusica/prevención & control , Radio (Anatomía)/fisiología , Receptores de Calcitriol/química , Receptores de Calcitriol/metabolismoRESUMEN
We conducted a study to determine whether increasing vitamin D intake above the recommended dietary allowance (RDA) of 5.0 micrograms (200 IU)/d reduces bone loss in healthy postmenopausal women residing at latitude 42 degrees N. In this double-blind, randomized 2-y trial, we enrolled 247 healthy ambulatory postmenopausal women who consumed an average of 2.5 micrograms (100 IU) vitamin D/d in their usual diets. The women were given either 2.5 micrograms (100 IU) or 17.5 micrograms (700 IU) vitamin D/d. All women received 500 mg supplemental calcium per day as citrate malate. Duplicate hip and spine and single whole-body scans were performed by dual-energy x-ray absorptiometry at 6-mo intervals selected to flank the periods when 25-hydroxycholecalciferol (calcidiol) concentrations are highest (summer/fall) and lowest (winter/spring). Plasma calcidiol and serum osteocalcin were measured in these seasons in year 1. Both treatment groups lost bone mineral density from the femoral neck, but the 17.5-micrograms group lost less than (-1.06 +/- 0.34%; mean +/- SE) the 2.5-micrograms group (-2.54 +/- 0.37%, P = 0.003). Seventy percent of the benefit each year occurred in winter/spring and 30% in summer/fall. Changes in spinal and whole-body bone densities did not differ by treatment group and were minimal after 2 y. Serum osteocalcin and plasma calcidiol (2.5-micrograms group only) fluctuated with season. In conclusion, in healthy, calcium-supplemented, postmenopausal women residing at latitude 42 degrees N, an intake of 5.0 micrograms (200 IU) vitamin D/d is sufficient to limit bone loss from the spine and whole body but it is not adequate to minimize bone loss from the femoral neck.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Osteoporosis Posmenopáusica/prevención & control , Osteoporosis Posmenopáusica/fisiopatología , Vitamina D/farmacología , Anciano , Densidad Ósea/efectos de los fármacos , Huesos/metabolismo , Calcifediol/sangre , Dieta , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Cuello Femoral/fisiopatología , Humanos , Persona de Mediana Edad , Necesidades Nutricionales , Osteocalcina/sangre , Osteoporosis Posmenopáusica/dietoterapia , Estaciones del Año , Columna Vertebral/fisiopatología , Vitamina D/uso terapéuticoRESUMEN
PURPOSE: To determine if walking, independently of other types of physical activity, influences bone density and rates of bone loss from the lumbar spine and whole body. PATIENTS AND METHODS: Healthy, white, postmenopausal women (n = 239) participating in a 1-year, placebo-controlled trial of vitamin D supplementation were studied. Bone densities of the lumbar spine and whole body were measured semiannually by dual-energy x-ray absorptiometry. Current and historical participation in outdoor walking and other leisure-time physical activities was assessed by questionnaire. RESULTS: Women who walk more than 7.5 miles per week had higher mean bone density of the whole body and of the legs and trunk regions of the body than women who walk less than 1 mile per week. The current level of walking activity was reflective of lifelong walking habits. The number of miles walked per week was also correlated with longitudinal rates of change in bone density at the legs (rp = 0.16, p = 0.03). CONCLUSIONS: Healthy postmenopausal women who walk approximately 1 mile each day have higher whole-body bone density than women who walk shorter distances. Walking is also effective in slowing the rate of bone loss from the legs. These results strongly support the widely held belief that walking is a beneficial form of physical activity for maintaining skeletal integrity.
Asunto(s)
Densidad Ósea , Osteoporosis Posmenopáusica/fisiopatología , Caminata , Adulto , Anciano , Índice de Masa Corporal , Femenino , Humanos , Pierna , Persona de Mediana Edad , Contracción Muscular , Osteoporosis Posmenopáusica/prevención & control , Vitamina D/uso terapéuticoRESUMEN
Two hundred eighty-four female adults (aged 40-70 years) were longitudinally studied to investigate the relationship between dietary supplemental vitamin A and serum biochemical markers of vitamin A toxicity. Serum retinol, retinyl esters, and retinol-binding protein (RBP), alkaline phosphatase and aspartate aminotransferase activities and bile acids were measured at baseline, 1 and 2 years. Fasting serum retinol and retinyl ester concentrations were determined by high-performance liquid chromatography, and dietary and supplemental intake of vitamin A were assessed by 3-day food records. There was no difference in dietary vitamin A intake between supplement users and nonusers. In supplemental users, the mean +/- SEM supplemental vitamin A intake was 952 +/- 81 IU/day (range 250-5000 retinol equivalents/day). Serum retinol, retinyl esters, and RBP concentrations were not different between the two groups during the 2-year period. For each group, serum retinyl esters significantly increased over time (p < 0.03), but the magnitude of the increase was not different between the groups. Serum levels of retinol, retinyl esters, and RBP were not correlated with vitamin A intake or age in either group. Biochemical measures of liver damage (serum alkaline phosphatase and aspartate aminotransferase activities and serum bile acids) were not related to serum retinol, retinyl esters or RBP concentrations, nor were they different between nonusers and users of supplemental vitamin A. This study provides evidence that long-term supplemental vitamin A in doses commonly found in multivitamin supplements does not present a risk for hypervitaminosis A.
Asunto(s)
Dieta , Pruebas de Función Hepática , Retinoides/sangre , Vitamina A/administración & dosificación , Adulto , Anciano , Fosfatasa Alcalina/sangre , Aspartato Aminotransferasas/sangre , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Proteínas de Unión al Retinol/metabolismo , Vitamina A/sangreRESUMEN
Fractional whole-body retention of 47Ca (retention fraction) in 58 healthy postmenopausal women participating in a calcium supplementation trial was examined for seasonal variation and for relationships to rates of bone loss and plasma vitamin D levels. Retention fraction was measured after 18 months in the trial. Bone mineral densities of the radius, femoral neck, and lumbar spine were measured at baseline, 12 months, and 24 months in the trial, and plasma 1,25-dihydroxyvitamin D [1,25-(OH)2D] and 25-hydroxyvitamin D (25-OHD) at 12, 18, and 24 months. The adjusted retention (retention fraction adjusted for total calcium intake, smoking status, and log years since menopause) was significantly higher in women evaluated in the months of August through October (mean +/- SD, 19.8 +/- 4.1%, n = 13) than in March through May (mean +/- SD, 17.0 +/- 4.7%, n = 18, p = 0.05). Plasma 25-OHD was associated with retention fraction only in women with low calcium intakes (partial r = 0.69 controlling for total calcium intake and log body mass index, n = 14, p = 0.01). Plasma 1,25-(OH)2D was not related to retention fraction. Adjusted retention, independent of total calcium intake, log years since menopause, smoking status, and season, explained 8% of the variability in the annual change in radius density (partial r = 0.29, p less than 0.05). No significant associations were seen at the spine and femur.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Resorción Ósea/metabolismo , Calcio/sangre , Menopausia/metabolismo , Estaciones del Año , Vitamina D/sangre , Anciano , Radioisótopos de Calcio , Femenino , Humanos , Persona de Mediana Edad , Valores de ReferenciaRESUMEN
OBJECTIVES: To determine whether relative vitamin D deficiency during the winter months contributes to age-related bone loss and whether rates of change in hard- and soft-tissue mass vary during the year. DESIGN: Double-blind, placebo-controlled, 1-year trial in 249 women in which equal numbers of women were randomized to either placebo or 400 IU of vitamin D daily. All women received 377 mg/d of supplemental calcium largely as calcium citrate malate. PATIENTS: Healthy, ambulatory postmenopausal women with usual intakes of vitamin D of 100 IU/d. MEASUREMENTS: Duplicate spine and whole-body scans were done by dual energy x-ray absorptiometry at 6-month intervals that were timed to periods when 25-hydroxyvitamin D levels were highest and lowest. Period 1 was June-July to December-January and period 2 was December-January to the next June-July. Serum parathyroid hormone and plasma 25-hydroxyvitamin D levels were measured during periods 1 and 2. MAIN RESULTS: In the placebo group, spinal bone mineral density increased in period 1, decreased in period 2, and sustained no net change. Women treated with vitamin D had a similar spinal increase in period 1 (1.46% compared with 1.40% in placebo), less loss in period 2 (-0.54% compared with -1.22%, CI for the difference, 0.05% to 1.31%, P = 0.032) and a significant overall benefit (0.85% compared with 0.15%, CI for the difference, 0.03% to 1.37%, P = 0.04). In period 2, 25-hydroxyvitamin D levels were lower and parathyroid hormone levels were higher in the placebo than in the vitamin D group. Whole-body lean and fat tissue and bone mineral density varied during the year but did not change overall. CONCLUSIONS: At latitude 42 degrees, healthy postmenopausal women with vitamin D intakes of 100 IU daily can significantly reduce late wintertime bone loss and improve net bone density of the spine over one year by increasing their intake of vitamin D to 500 IU daily. A long-term benefit of preventing vitamin D insufficiency in the winter seems likely although it remains to be shown. Observed changes in bone as well as in fat and lean tissue appear to be related to season.
Asunto(s)
Densidad Ósea/efectos de los fármacos , Osteoporosis Posmenopáusica/tratamiento farmacológico , Vitamina D/uso terapéutico , Absorciometría de Fotón , Composición Corporal/efectos de los fármacos , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/sangre , Osteoporosis Posmenopáusica/metabolismo , Estaciones del Año , Columna Vertebral/química , Columna Vertebral/diagnóstico por imagen , Vitamina D/sangreRESUMEN
We examined the effect of smoking on bone mineral density (BMD), rates of bone loss, and fractional whole-body retention of 47Ca in healthy postmenopausal women enrolled in a 2-year calcium supplementation trial. Bone density was measured by single- and dual-photon absorptiometry. BMD of the radius at the study baseline was inversely related to pack-years of exposure when controlled for body mass index and years since menopause (partial r = -0.18, p = 0.05, n = 125). The adjusted mean (+/- SD) annualized rate of bone change from the radius was greater among smokers than nonsmokers (-0.914 +/- 2.624%/year, n = 34, versus 0.004 +/- 2.568%/year, n = 278, respectively; p = 0.05). Similar trends were observed at the femoral neck, os calcis, and spine. Rates were were adjusted for caffeine intake, alcohol use, supplement type, and, at the spine only, menopausal status. At entry into the trial higher serum levels of alkaline phosphatase and lower levels of total and ionized calcium were found in smokers compared to nonsmokers. These differences did not persist with supplementation. In 44 women studied fractional 47Ca retention was lower in the 8 smokers than the 36 nonsmokers (16.6 versus 19.1%, respectively; p = 0.03). These results demonstrate an increased rate of bone loss at the radius after menopause and suggest that smoking is associated with decreased calcium absorption.
Asunto(s)
Osteoporosis Posmenopáusica/etiología , Fumar/efectos adversos , Adulto , Anciano , Densidad Ósea/fisiología , Calcio/metabolismo , Dieta , Femenino , Humanos , Persona de Mediana Edad , Factores de RiesgoRESUMEN
Background. The effectiveness of calcium in retarding bone loss in older postmenopausal women is unclear. Earlier work suggested that the women who were most likely to benefit from calcium supplementation were those with low calcium intakes. Methods. We undertook a double-blind, placebo-controlled, randomized trial to determine the effect of calcium on bone loss from the spine, femoral neck, and radius in 301 healthy postmenopausal women, half of whom had a calcium intake lower than 400 mg per day and half an intake of 400 to 650 mg per day. The women received placebo or either calcium carbonate or calcium citrate malate (500 mg of calcium per day) for two years. Results. In women who had undergone menopause five or fewer years earlier, bone loss from the spine was rapid and was not affected by supplementation with calcium. Among the women who had been postmenopausal for six years or more and who were given placebo, bone loss was less rapid in the group with the higher dietary calcium intake. In those with the lower calcium intake, calcium citrate malate prevented bone loss during the two years of the study; its effect was significantly different from that of placebo (P less than 0.05) at the femoral neck (mean change in bone density [+/- SE], 0.87 +/- 1.01 percent vs. -2.11 +/- 0.93 percent), radius (1.05 +/- 0.75 percent vs. -2.33 +/- 0.72 percent), and spine (-0.38 +/- 0.82 percent vs. -2.85 +/- 0.77 percent). Calcium carbonate maintained bone density at the femoral neck (mean change in bone density, 0.08 +/- 0.98 percent) and radius (0.24 +/- 0.70 percent) but not the spine (-2.54 +/- 0.85 percent). Among the women who had been postmenopausal for six years or more and who had the higher calcium intake, those in all three treatment groups maintained bone density at the hip and radius and lost bone from the spine. Conclusions. Healthy older postmenopausal women with a daily calcium intake of less than 400 mg can significantly reduce bone loss by increasing their calcium intake to 800 mg per day. At the dose we tested, supplementation with calcium citrate malate was more effective than supplementation with calcium carbonate.