Vitamin D status among patients with fractured neck of femur in Hong Kong

Unveiling the Metabolic Mystery of Fragility Hip Fracture in Indian Patients: A Histomorphometric and Biochemical Correlation

BACKGROUND

High prevalence of hypovitaminosis D is being reported in Indian patients with fragility hip fracture. The gold standard to diagnose osteoporosis and osteomalacia is bone histomorphometry. There is no study evaluating histopathological histomorphometry in Indian fragility hip fracture patients. The purpose of the study was to evaluate fragility hip fracture patients for histopathological osteomalacia and osteoporosis by histomorphometry and to correlate histopathological findings with biochemical hypovitaminosis D.

MATERIALS AND METHODS

A total of 55 patients of fragility hip fractures recruited for prospective cross-sectional study. During definitive fracture fixation of these fragility hip fractures, bone biopsy taken from neck region of femur by a novel approach for histomorphometry. Histomorphometric analysis was based on three indices, namely osteoid seam width, osteoblast surface, and osteoid surface. We also analysed blood bone biochemistry and correlated with bone histomorphometry.

RESULTS

In fragility hip fracture patients, the prevalence of histomorphometric osteoporosis and osteomalacia were very low (only 9.4% had osteoporosis and none had osteomalacia) however in blood bone biochemistry, we found high prevalence (85.5%) of hypovitaminosis D. We also noted significant changes when correlated bone histomorphometry with different blood bone biochemistry.

CONCLUSION

Indian patients with fragility hip fracture were found to have high prevalence of biochemical hypovitaminosis D but unlike western literature, there was low prevalence of histomorphometric osteoporosis with no evidence of histomorphometric osteomalacia. Correct knowledge about metabolic status of fragility hip fracture is required to improve outcome, decrease complications and to optimise cost of the treatment.

Insufficiency and deficiency of vitamin D in elderly patients with fragility fractures of the hip in the Japanese population

BACKGROUND

Data of vitamin D sufficiency in Asian patients with osteoporotic fragility hip fractures are limited. This study aimed to obtain data from the Japanese population.

METHODS

Patients aged 60 years or older with hip fractures were prospectively enrolled. Serum 25-hydroxyvitamin D (25(OH)D) levels were measured. Levels were compared between patients receiving and not receiving treatment for osteoporosis, those with and without previous contralateral hip fractures, and those with femoral neck versus trochanteric fractures. Sex-based differences were also assessed. The serum levels in patients younger than 60 years with extremity fractures were assessed, and differences between elderly and younger patients were evaluated. The individual correlation between 25(OH)D levels and the ultraviolet (UV) index and age was analyzed in elderly patients with hip fractures.

RESULTS

The data of 360 patients (aged 84.7 ± 8.2 years), comprising 80 men and 280 women, were analyzed. The mean 25(OH)D level was 16.5 ± 7.2 ng/mL. The prevalence of vitamin D insufficiency (25(OH)D <30 ng/mL) and deficiency (25(OH)D <20 ng/mL) was 93.9% and 71.7%, respectively. A significant difference was noted in the prevalence of vitamin D deficiency between patients with and without previous contralateral hip fractures. Age and 25(OH)D levels were found to be correlated, with no correlation between the UV index and the 25(OH)D levels. The 25(OH)D level in the younger population (n = 123) was 20.7 ± 8.6 ng/mL, which was significantly higher than that of the elderly.

CONCLUSION

Perennial vitamin D insufficiency is prevalent in elderly Japanese patients with hip fractures.

What Is the Role of Vitamin D Supplementation in Acute Fracture Patients? A Systematic Review and Meta-Analysis of the Prevalence of Hypovitaminosis D and Supplementation Efficacy

OBJECTIVES

The objectives of this systematic review and meta-analyses are (1) to estimate the prevalence of hypovitaminosis D in fracture patients and (2) to summarize the available evidence on the efficacy of vitamin D supplementation in fracture patients.

DATA SOURCES

A comprehensive search of the MEDLINE, Embase, PubMed, and Cochrane Central Register of Controlled Trials databases was conducted. Conference abstracts from relevant meetings were also searched.

STUDY SELECTION

We included studies that investigate vitamin D insufficiency or examine the effect of vitamin D supplementation on 25-hydroxy-vitamin D (25(OH)D) serum levels in fracture patients.

DATA EXTRACTION

Two authors independently extracted data using a predesigned form.

DATA SYNTHESIS

We performed a pooled analysis to determine the prevalence of postfracture hypovitaminosis D and mean postfracture 25(OH)D levels. We present detailed summaries of each of the studies evaluating the impact of vitamin D supplementation.

RESULTS

The weighted pooled prevalence of hypovitaminosis D was 70.0% (95% confidence interval: 63.7%-76.0%, I = 97.7). The mean postfracture serum 25(OH)D was 19.5 ng/mL. The studies that evaluated the efficacy of vitamin D supplementation suggest that vitamin D supplementation safely increases serum 25(OH)D levels. Only 1 meeting abstract showed a trend toward reduced risk of nonunion after a single large loading dose of vitamin D.

CONCLUSIONS

This review found a high prevalence of hypovitaminosis D in fracture patients and that vitamin D supplementation at a range of doses safely increases 25(OH)D serum levels. To date, only 1 pilot study published as a meeting abstract has demonstrated a trend toward improved fracture healing with vitamin D supplementation.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Efficacy of optimization of vitamin D in preventing osteoporosis and osteoporotic fractures: A systematic review

Increased intake or supplementation of vitamin D is often recommended for normal bone health; however, its preventive effect on osteoporosis has not been fully evaluated. The aim of this review is to gather evidence of the efficacy of the optimization of vitamin D nutrition in preventing osteoporosis and osteoporotic fractures. PubMed was used for searching the relevant literature using the MeSH terms "Bone Density (limited to "human", "female", and "English" literature)" or "Fractures (limited to "human", "age ≥45 years", and "English" literature)", and "Vitamin D". The searches yielded 19 randomized controlled trials (RCTs), nine cohort studies, 19 case-control studies, 19 cross-sectional studies, and one meta-analysis. We attempted to answer three questions: 1) does increased vitamin D intake prevent bone loss in peri- and postmenopausal women?, 2) does increased vitamin D intake prevent osteoporotic fractures in the elderly?, and 3) does increased vitamin D in take positively affect peak bone mass attainment in young women? The answer to questions 1 and 2 is that a vitamin D intake of 10-17.5 μg/day (400-700 IU/day) or more is effective in preventing bone loss in late postmenopausal women and an intake of 17.5-20 μg/day (700-800 IU/day) or more together with a calcium supplement reduces the risk of osteoporotic fractures. For question 3, some lines of evidence support the negative effect of low vitamin D nutrition on the attainment of peak bone mass in young women. Further studies are needed to clarify the effect of vitamin D in this age group.

Hip fracture risk in relation to vitamin D supplementation and serum 25-hydroxyvitamin D levels: a systematic review and meta-analysis of randomised controlled trials and observational studies

BACKGROUND

Vitamin D supplementation for fracture prevention is widespread despite conflicting interpretation of relevant randomised controlled trial (RCT) evidence. This study summarises quantitatively the current evidence from RCTs and observational studies regarding vitamin D, parathyroid hormone (PTH) and hip fracture risk.

METHODS

We undertook separate meta-analyses of RCTs examining vitamin D supplementation and hip fracture, and observational studies of serum vitamin D status (25-hydroxyvitamin D (25(OH)D) level), PTH and hip fracture. Results from RCTs were combined using the reported hazard ratios/relative risks (RR). Results from case-control studies were combined using the ratio of 25(OH)D and PTH measurements of hip fracture cases compared with controls. Original published studies of vitamin D, PTH and hip fracture were identified through PubMed and Web of Science databases, searches of reference lists and forward citations of key papers.

RESULTS

The seven eligible RCTs identified showed no significant difference in hip fracture risk in those randomised to cholecalciferol or ergocalciferol supplementation versus placebo/control (RR = 1.13[95%CI 0.98-1.29]; 801 cases), with no significant difference between trials of <800 IU/day and > or = 800 IU/day. The 17 identified case-control studies found 33% lower serum 25(OH)D levels in cases compared to controls, based on 1903 cases. This difference was significantly greater in studies with population-based compared to hospital-based controls (chi(2)(1) (heterogeneity) = 51.02, p < 0.001) and significant heterogeneity was present overall (chi(2)(16) (heterogeneity) = 137.9, p < 0.001). Serum PTH levels in hip fracture cases did not differ significantly from controls, based on ten case-control studies with 905 cases (chi(2)(9) (heterogeneity) = 149.68, p < 0.001).

CONCLUSIONS

Neither higher nor lower dose vitamin D supplementation prevented hip fracture. Randomised and observational data on vitamin D and hip fracture appear to differ. The reason for this is unclear; one possible explanation is uncontrolled confounding in observational studies. Post-fracture PTH levels are unrelated to hip fracture risk.

Global vitamin D status and determinants of hypovitaminosis D

This review describes the vitamin D status in different regions of the world with the objective of understanding the scope of hypovitaminosis D and the factors related to its prevalence that may contribute to the pathogenesis of osteoporosis and fragility fractures.

INTRODUCTION

Vitamin D status has been linked to the pathogenesis of hip fractures as well as other skeletal and non-skeletal disorders. The purpose of this review is to provide a global perspective of vitamin D status across different regions of the world and to identify the common and significant determinants of hypovitaminosis D.

METHODS

Six regions of the world were reviewed-Asia, Europe, Middle East and Africa, Latin America, North America, and Oceania-through a survey of published literature.

RESULTS

The definition of vitamin D insufficiency and deficiency, as well as assay methodology for 25-hydroxyvitamin D or 25(OH)D, vary between studies. However, serum 25(OH)D levels below 75 nmol/L are prevalent in every region studied whilst levels below 25 nmol/L are most common in regions such as South Asia and the Middle East. Older age, female sex, higher latitude, winter season, darker skin pigmentation, less sunlight exposure, dietary habits, and absence of vitamin D fortification are the main factors that are significantly associated with lower 25(OH)D levels.

CONCLUSION

Reports from across the world indicate that hypovitaminosis D is widespread and is re-emerging as a major health problem globally.

Vitamin D inadequacy in postmenopausal women in Eastern Asia

OBJECTIVE

To review data on the prevalence of vitamin D inadequacy and its causes in postmenopausal women in Eastern Asia.

RESEARCH DESIGN AND METHOD

Data were obtained from the published biomedical literature as well as abstracts and posters presented at scientific meetings. Using MEDLINE, EMBASE and BIOSIS databases (to July 2007), epidemiological studies were identified using the search terms: 'human', 'vitamin D', 'vitamin D deficiency', 'vitamin D inadequacy', 'vitamin D insufficiency' and 'hypovitaminosis D', 'osteomalacia' and 'osteoporosis'. Additional references were also identified from the bibliographies of published articles.

RESULTS

The prevalence of vitamin D inadequacy in studies of postmenopausal women (ambulatory or with osteoporosis or related musculoskeletal disorders) in Eastern Asia ranged from 0 to 92%, depending on the cut-off level of serum 25-hydroxycholecalciferol [25(OH)D] that was applied (range < or =6-35 ng/mL [< or = 15-87 nmol/L]). One large international study found that 71% of postmenopausal women with osteoporosis in Eastern Asia had vitamin D inadequacy, defined as serum levels of 25(OH)D < 30 ng/mL (75 nmol/L). Prevalence rates using this cut-off level were 47% in Thailand, 49% in Malaysia, 90% in Japan and 92% in South Korea. High prevalences of vitamin D inadequacy were evident in two studies using a lower 25(OH)D level cut-off value of < 12 ng/mL (30 nmol/L) - 21% in China and 57% in South Korea. Dietary deficiency and inadequate exposure or reactivity to sunlight (due to lifestyle choices, cultural customs and/or aging) were identified as important risk factors for vitamin D inadequacy.

CONCLUSIONS

Non-uniform, epidemiological studies indicate a high prevalence of vitamin D inadequacy in postmenopausal women in Eastern Asia. Recommended remedial approaches are education campaigns and broad-based provision of vitamin D supplementation.

Vitamin D intake: a global perspective of current status

Global high prevalence of vitamin D insufficiency and re-emergence of rickets and the growing scientific evidence linking low circulating 25-hydroxyvitamin D to increased risk of osteoporosis, diabetes, cancer, and autoimmune disorders have stimulated recommendations to increase sunlight (UVB) exposure as a source of vitamin D. However, concern over increased risk of melanoma with unprotected UVB exposure has led to the alternative recommendation that sufficient vitamin D should be supplied through dietary sources alone. Here, we examine the adequacy of vitamin D intake worldwide and evaluate the ability of current fortification policies and supplement use practices among various countries to meet this recommendation. It is evident from our review that vitamin D intake is often too low to sustain healthy circulating levels of 25-hydroxyvitamin D in countries without mandatory staple food fortification, such as with milk and margarine. Even in countries that do fortify, vitamin D intakes are low in some groups due to their unique dietary patterns, such as low milk consumption, vegetarian diet, limited use of dietary supplements, or loss of traditional high fish intakes. Our global review indicates that dietary supplement use may contribute 6-47% of the average vitamin D intake in some countries. Recent studies demonstrate safety and efficacy of community-based vitamin D supplementation trials and food staple fortification introduced in countries without fortification policies. Reliance on the world food supply as an alternative to UVB exposure will necessitate greater availability of fortified food staples, dietary supplement use, and/or change in dietary patterns to consume more fish.

Vitamin D deficiency and secondary hyperparathyroidism in the elderly: consequences for bone loss and fractures and therapeutic implications

Vitamin D deficiency is common in the elderly, especially in the housebound and in geriatric patients. The establishment of strict diagnostic criteria is hampered by differences in assay methods for 25-hydroxyvitamin D. The synthesis of vitamin D3 in the skin under influence of UV light decreases with aging due to insufficient sunlight exposure, and a decreased functional capacity of the skin. The diet contains a minor part of the vitamin D requirement. Vitamin D deficiency in the elderly is less common in the United States than elsewhere due to the fortification of milk and use of supplements. Deficiency in vitamin D causes secondary hyperparathyroidism, high bone turnover, bone loss, mineralization defects, and hip and other fractures. Less certain consequences include myopathy and falls. A diet low in calcium may cause an increased turnover of vitamin D metabolites and thereby aggravate vitamin D deficiency. Prevention is feasible by UV light exposure, food fortification, and supplements. Vitamin D3 supplementation causes a decrease of the serum PTH concentration, a decrease of bone turnover, and an increase of bone mineral density. Vitamin D3 and calcium may decrease the incidence of hip and other peripheral fractures in nursing home residents. Vitamin D3 is recommended in housebound elderly, and it may be cost-effective in hip fracture prevention in selected risk groups.

Calcium, dairy products and osteoporosis

Osteoporosis is a multifactorial disorder in which nutrition plays a role but does not account for the totality of the problem. 139 papers published since 1975 and describing studies of the relationship of calcium intake and bone health are briefly analyzed. Of 52 investigator-controlled calcium intervention studies, all but two showed better bone balance at high intakes, or greater bone gain during growth, or reduced bone loss in the elderly, or reduced fracture risk. This evidence firmly establishes that high calcium intakes promote bone health. Additionally, three-fourths of 86 observational studies were also positive, indicating that the causal link established in investigator-controlled trials can be found in free-living subjects as well. The principal reason for failure to find an association in observational studies is the weakness of the methods available for estimating long-term calcium intake. While most of the investigator-controlled studies used calcium supplements, six used dairy sources of calcium; all were positive. Most of the observational studies were based on dairy calcium also, since at the time the studies were done, higher calcium intakes meant higher dairy intakes. All studies evaluating the issue reported substantial augmentation of the osteoprotective effect of estrogen by high calcium intakes. Discussion is provided in regard to the multifactorial complexity of osteoporotic response to interventions and to the perturbing effect in controlled trials of the bone remodeling transient, as well as about how inferences can validly be drawn from the various study types represented in this compilation.

Secondary hyperparathyroidism in patients from Western Australia with hip fracture: relationship to type of hip fracture, renal function, and vitamin D deficiency

OBJECTIVES

To determine the frequency of vitamin D deficiency and secondary hyperparathyroidism in Australian hip fracture patients living in the community.

PATIENTS

A total of 283 consecutive patients with hip fracture admitted over a 15-month period to a university teaching hospital in Western Australia. Included were residents of hostels for the elderly, and excluded were nursing home residents and those with malignant fractures.

METHOD

Data collected included biochemistry (25 hydroxyvitamin D, parathyroid hormone and creatinine levels), measurements of function and disability (Barthel Index, Frenchay Activity Index), sunshine exposure, and basic demographics.

RESULTS

Vitamin D deficiency occurred in 31.7% and secondary hyperparathyroidism occurred in 17.7% of cases. The major determinants of vitamin D deficiency were outdoor sunshine exposure, ambient daily sunshine, and disability (low Frenchay Activity Index or ADL difficulty). Secondary hyperparathyroidism was related to older age, renal dysfunction, and vitamin D deficiency. Secondary hyperparathyroidism was associated with an excess of trochanteric over subcapital hip fractures.

CONCLUSIONS

Secondary hyperparathyroidism appears to be a heterogeneous condition, caused in approximately equal proportions by vitamin D deficiency and renal dysfunction, that may confer increased cortical bone fragility and trochanteric fractures. Renal dysfunction in old age may be an important additional determinant of senile osteoporosis, which has implications for preventive therapy. Vitamin D deficiency occurs in disabled and, presumably, housebound older people despite near optimal climatic conditions.

Age-related (type II) femoral neck osteoporosis in men: biochemical evidence for both hypovitaminosis D- and androgen deficiency-induced bone resorption

The problem of osteoporosis in men has recently been recognized as an important public health issue. To test the hypothesis that endocrine deficiency-mediated alterations in bone metabolism might contribute to osteoporotic fracture risk in elderly men, serum levels of 25-hydroxycholecalciferol (25(OH)D), 1,25-dihydroxycholecalciferol (1,25(OH)2D), intact parathyroid hormone (PTH), testosterone, and estradiol were measured in 40 males (mean age 73 years) who were consecutively recruited within 18 h following a fracture of the proximal femur, and in an equal number of community-living older men (mean age 72 years) who served as controls. In addition, circulating osteocalcin and urinary excretion of (deoxy)pyridinoline were determined as markers of bone formation and resorption, respectively. No differences were observed between the mean serum concentrations of osteocalcin and estradiol. Serum levels of 25(OH)D, 1,25(OH)2D, and testosterone, however, were decreased in hip fracture patients. When correcting for differences in vitamin D binding protein, differences in 1,25(OH)2D did not persist, whereas serum 25(OH)D was still significantly lower in patients than in controls (6.1 +/- 4.3 vs. 7.6 +/- 2.8, p = 0.01). Similarly, a highly significant deficit was observed in the free testosterone index, calculated from total testosterone and the level of sex hormone binding globulin (2.6 +/- 1.3 vs. 8.2 +/- 2.9, p < 0.001). Serum PTH and urinary pyridinium cross-links, however, were markedly increased in the fracture group. Moreover, in fracture patients, free 25(OH)D and free testosterone were both significant and mutually independent negative predictors of (deoxy)pyridinoline excretion. Although limited by its cross-sectional design, the present study suggests that both hypovitaminosis D and androgen deficiency may predispose to bone resorption in elderly men and in turn to remodeling imbalance and fracture risk.

Vitamin D stores of urban women in Taipei: effect on bone density and bone turnover, and seasonal variation

This study was performed to survey the vitamin D nutritional status of urban Chinese women, and to define its role in determining bone metabolic rate and bone mineral density (BMD). We measured serum 25-hydroxyvitamin D (25-OHD), the major storage form of vitamin D, and BMD, at the spine, hip, and total body skeleton, of 262 healthy Chinese women aged from 40 to 72 years, residing in Taipei city. Bone turnover markers, including serum osteocalcin, bone alkaline phosphatase isozyme, and C-terminal propeptide of type I procollagen, and a urinary bone resorption marker, N-terminal crosslinked fragment of type I collagen, were also measured. We found generally adequate vitamin D nutritional stores. The mean concentration of serum 25-OHD was 30.7 (SD = 8.2) ng/mL for all 262 subjects and there were no significant age-related changes. Those who had serum sampled during the summer showed higher serum 25-OHD levels (N = 138; mean +/- SD: 32.7 +/- 7.6 ng/mL) than those who had serum sampled during winter (N = 124; mean +/- SD: 28.5 +/- 8.3 ng/mL; Student's t-test, p < 0.001), but these two groups showed similar BMD and bone marker values. Those with serum 25-OHD concentration in the lowest or highest tertile did not show different BMD or bone marker values than those in the other tertiles. Multiple regression demonstrated no correlation between 25-OHD and any bone marker or BMD at any site. Thus, in this free-living urban Chinese population, in a subtropical region, we could not demonstrate a role of vitamin D stores in determining bone turnover rate or BMD in women aged 40-70 years.

Calciotropic hormones in elderly people with and without hip fracture

The effects of age on calciotropic hormones are not completely understood. The presence of secondary hyperparathyroidism has previously been demonstrated, particularly in patients with hip fracture. The role of a disturbance of vitamin D metabolism, especially a defect in 1 alpha-hydroxylation, is debated. The aim of this study was to compare serum parathyroid hormone (PTH), osteocalcin and vitamin D metabolites (25(OH)D and 1,25(OH)2D) in osteoporotic elderly patients with hip fracture (HF) and in elderly controls. We studied 57 HF patients aged 83.9 +/- 5.9 years (mean +/- SD) and 68 controls aged 82.5 +/- 5 years recruited during two periods: 1 January and 30 April 1988 and 1989. Patients with chronic renal failure (serum creatinine above 150 mumol/l), cancer, or other metabolic bone disease were excluded. Thirty healthy young adults were studied in 1989 only for measurement of 1,25(OH)2D. (1,25(OH)2D was measured by different laboratories in 1988 and 1989 for technical reasons.) We also measured serum PTH, osteocalcin, total calcium and ionized calcium. 1,25(OH)2D levels were not statistically different between HF patients and controls for the two years, nor between HF patients and young healthy adults in 1989. 25(OH)D was decreased in HF patients (p < 0.003), as was ionized calcium. Serum PTH levels were higher in HF patients than in controls (p < 0.01). A positive correlation has been found between PTH and age in HF patients (r = 0.29; p < 0.03) and in the whole group of HF patients and controls. There was a significant decrease in osteocalcin in HF patients versus elderly controls (p < 0.04).(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of osteoporosis in the elderly

Fracture risk is adversely related to bone density, wherever it is measured. Women should be screened by bone densitometry around the time of the menopause and treated with calcium or hormones if the density is low. Women with vertebral compression should be treated with calcitriol if calcium absorption is low, with hormones if urine calcium is high, and with calcitriol and hormones if both abnormalities are present. It is uncertain whether newer treatments offer any advantages over this regimen. Vitamin D is indicated in household individuals or others with low levels of 25 OHD to prevent loss from secondary hyperparathyroidism and perhaps also to improve muscle power.

Serum intact parathyroid hormone levels in elderly Chinese females with hip fracture

Serum intact parathyroid hormone (PTH), 25 hydroxyvitamin D(25OHD), 1,25 dihydroxyvitamin D (1,25(OH)2D), albumin, and ionized calcium were measured in 61 Chinese female patients with hip fracture and 61 control subjects. Hip fracture patients had low albumin, ionized calcium, and 250HD levels. Serum PTH and 1,25(OH)2D values were not different between the two groups. We conclude that although 250HD level in hip fracture patients is low, there is no evidence of secondary hyperparathyroidism, suggesting that the low 250HD levels may be a secondary phenomenon in response to the fracture.

Differences in vitamin D status between countries in young adults and the elderly

PURPOSE

To compare vitamin D status between countries in young adults and in the elderly.

MATERIALS AND METHODS

Reports on vitamin D status (as assessed by serum 25-hydroxyvitamin D) from 1971 to 1990 were reviewed. Studies were grouped according to geographic regions: North America (including Canada and the United States); Scandinavia (including Denmark, Finland, Norway, and Sweden); and Central and Western Europe (including Belgium, France, Germany, Ireland, The Netherlands, Switzerland, and the United Kingdom).

RESULTS

Vitamin D status varies with the season in young adults and in the elderly, and is lower during the winter in Europe than in both North America and Scandinavia. Oral vitamin D intake is lower in Europe than in both North America and Scandinavia. Hypovitaminosis D and related abnormalities in bone chemistry are most common in elderly residents in Europe but are reported in all elderly populations.

CONCLUSIONS

The vitamin D status in young adults and the elderly varies widely with the country of residence. Adequate exposure to summer sunlight is the essential means to ample supply, but oral intake augmented by both fortification and supplementation is necessary to maintain baseline stores. All countries should adopt a fortification policy. It seems likely that the elderly would benefit additionally from a daily supplement of 10 micrograms of vitamin D.