There is high quality evidence that vitamin D plus calcium is associated with a statistically significant reduction in incidence of new non-vertebral fractures .
Vitamin D alone is unlikely to prevent fractures in the doses and formulations tested so far in older people .
Supplements of vitamin D and calcium may prevent hip or any type of fracture .
There was a small but significant increase in gastrointestinal symptoms and renal disease associated with vitamin D and calcium .
This review found that there was no increased risk of death from taking calcium and vitamin
BACKGROUND Vitamin D and related compounds have been used to prevent  osteoporotic fractures in older people .
This is the third up date of a Cochrane review first published in 1996 .
OBJECTIVES To determine the effects of vitamin D or related compounds , with or without calcium , for preventing  fractures in post-menopausal women and older men .
Dose Response to Vitamin D Supplementation in Postmenopausal Women
BACKGROUND Serum 25-hydroxyvitamin D ( 25-[OH]D ) is considered the best biomarker of clinical vitamin D status . OBJECTIVE To determine the effect of increasing oral doses of vitamin D(3 ) on serum 25-(OH)D and serum parathyroid hormone ( PTH ) levels in postmenopausal white women with vitamin D insufficiency ( defined as a 25-[OH]D level ≤50 nmol/L ) in the presence of adequate calcium intake . These results can be used as a guide to estimate the Recommended Dietary Allowance ( RDA ) ( defined as meeting the needs of 97.5 % of the population ) for vitamin D(3 ) . DESIGN R and omized , placebo-controlled trial . ( Clinical Trials.gov registration number : NCT00472823 ) SETTING Creighton University Medical Center , Omaha , Nebraska . PARTICIPANTS 163 healthy postmenopausal white women with vitamin D insufficiency enrolled in the winter or spring of 2007 to 2008 and followed for 1 year . INTERVENTION Participants were r and omly assigned to receive placebo or vitamin D(3 ) , 400 , 800 , 1600 , 2400 , 3200 , 4000 , or 4800 IU once daily . Daily calcium supplements were provided to increase the total daily calcium intake to 1200 to 1400 mg . MEASUREMENTS The primary outcomes were 25-(OH)D and PTH levels at 6 and 12 months . RESULTS The mean baseline 25-(OH)D level was 39 nmol/L. The dose response was curvilinear and tended to plateau at approximately 112 nmol/L in patients receiving more than 3200 IU/d of vitamin D(3 ) . The RDA of vitamin D(3 ) to achieve a 25-(OH)D level greater than 50 nmol/L was 800 IU/d . A mixed-effects model predicted that 600 IU of vitamin D(3 ) daily could also meet this goal . Compared with participants with a normal body mass index ( < 25 kg/m(2 ) ) , obese women ( ≥30 kg/m(2 ) ) had a 25-(OH)D level that was 17.8 nmol/L lower . Parathyroid hormone levels at 12 months decreased with an increasing dose of vitamin D(3 ) ( P = 0.012 ) . Depending on the criteria used , hypercalcemia occurred in 2.8 % to 9.0 % and hypercalciuria in 12.0 % to 33.0 % of participants ; events were unrelated to dose . LIMITATION Findings may not be generalizable to other age groups or persons with substantial comorbid conditions . CONCLUSION A vitamin D(3 ) dosage of 800 IU/d increased serum 25-(OH)D levels to greater than 50 nmol/L in 97.5 % of women ; however , a model predicted the same response with a vitamin D(3 ) dosage of 600 IU/d . These results can be used as a guide for the RDA of vitamin D(3 ) , but prospect i ve trials are needed to confirm the clinical significance of these results . PRIMARY FUNDING SOURCE National Institute on Aging
There is high quality evidence that vitamin D plus calcium is associated with a statistically significant reduction in incidence of new non-vertebral fractures .
Vitamin D alone is unlikely to prevent fractures in the doses and formulations tested so far in older people .
Supplements of vitamin D and calcium may prevent hip or any type of fracture .
There was a small but significant increase in gastrointestinal symptoms and renal disease associated with vitamin D and calcium .
This review found that there was no increased risk of death from taking calcium and vitamin
BACKGROUND Vitamin D and related compounds have been used to prevent  osteoporotic fractures in older people .
This is the third up date of a Cochrane review first published in 1996 .
OBJECTIVES To determine the effects of vitamin D or related compounds , with or without calcium , for preventing  fractures in post-menopausal women and older men .