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Elevated homocysteine levels and low vitamin B12 and folate levels have been associated with deteriorated bone health. This systematic literature review with dose-response meta-analyses summarizes the available scientific evidence on associations of vitamin B12, folate, and homocysteine status with fractures and bone mineral density (BMD). Twenty-seven eligible cross-sectional (n=14) and prospective (n=13) observational studies and one RCT were identified. Meta-analysis on four prospective studies including 7475 people showed a modest decrease in fracture risk of 4% per 50 pmol/L increase in vitamin B12 levels, which was borderline significant (RR = 0.96, 95% CI = 0.92 to 1.00). Meta-analysis of eight studies including 11511 people showed an increased fracture risk of 4% per μmol/L increase in homocysteine concentration (RR = 1.04, 95% CI = 1.02 to 1.07). We could not draw a conclusion regarding folate levels and fracture risk, as too few studies investigated this association. Meta-analyses regarding vitamin B12, folate and homocysteine levels, and BMD were possible in female populations only and showed no associations. Results from studies regarding BMD that could not be included in the meta-analyses were not univocal.

Contains fulltext : 48022.pdf (Publisher’s version ) (Closed access) BACKGROUND: A high prevalence of cobalamin deficiency occurs in the elderly population, which may be treated orally or with injections. Little is known about the relative bioavailability of crystalline cobalamin added to food products. OBJECTIVE: The objective was to assess the effect of supplementation with 1000 microg crystalline cobalamin, carried either by a milk product or a capsule, on cobalamin status in mildly cobalamin-deficient elderly Dutch persons. DESIGN: Two double-blind randomized controlled intervention studies, each covering a 12-wk supplementation period, were carried out in parallel. Mildly cobalamin-deficient elderly persons (n = 112) were separately recruited for the milk and capsule trials. Mild cobalamin deficiency was defined as a cobalamin concentration between 100 and 300 pmol/L and a plasma methylmalonic acid (MMA) concentration > or = 0.30 micromol/L. Allocation to the placebo or cobalamin carrier was carried out independently in both trials. RESULTS: In the fortified-milk group, the mean (+/-SD) increase in serum cobalamin was 250 +/- 96 pmol/L, the median (5th and 95th percentiles) decrease in plasma MMA was 0.19 (-0.76, -0.04) micromol/L, and the median decrease in plasma homocysteine was 4.0 (-7.3, 3.0) micromol/L. All changes were significantly different from those in the placebo milk group (P < 0.01). Likewise, in the cobalamin-capsule group, the mean increase in serum cobalamin was 281 +/- 136 pmol/L, the median decrease in plasma MMA was 0.18 (-2.95, 0.14) micromol/L, and the median decrease in plasma homocysteine was 1.8 (-10.6, 2.4) micromol/L; all changes were significantly different from those in the placebo capsule group (P < 0.01). No significant differences were observed between the fortified-milk and capsule groups (P > 0.40). CONCLUSION: Crystalline cobalamin added to milk is an effective alternative to cobalamin capsules for improving cobalamin status.

Subclinical vitamin B-12 deficiency is common in the elderly. Encouraged by early indications, we investigated the plasma vitamin B-12 status in association with bone mineral content (BMC) and bone mineral density (BMD) in frail elderly people. Data of 194 free-living Dutch frail elderly (143 women and 51 men) were available. BMC and BMD were measured by dual energy X-ray analysis. Biochemical analyses were performed on plasma or serum including vitamin B-12, methylmalonic acid, homocysteine, 25-hydroxy vitamin D and parathyroid hormone. Women had higher plasma vitamin B-12 (288 and 238 pmol/L, respectively) and lower plasma homocysteine levels (15.8 and 21.3 μmol/L, respectively) than men. Of the total explained variance of BMC and BMD in women (46 and 22%, respectively), 1.3-3.1% was explained by plasma vitamin B-12, in addition to weight and height or energy intake. In men, the variance of BMC and BMD was explained by weight, smoking and/or height (total R2 was 53 and 25%, respectively), but not by plasma vitamin B-12. Osteoporosis occurred more often among women whose vitamin B-12 status was considered marginal or deficient than in women with a normal status, i.e., the prevalence odds ratios (after adjustment for weight, age and calcium intake) (95% confidence intervals) were 4.5 (0.8; 24.8) and 6.9 (1.2;39.4), respectively. These results suggest that vitamin B-12 status is associated with bone health in elderly women. Future studies on bone health should take into account a possible role of vitamin B-12 status in different populations. Chemicals/CAS: 25 hydroxyvitamin D, 64719-49-9; cyanocobalamin, 53570-76-6, 68-19-9, 8064-09-3; homocysteine, 454-28-4, 6027-13-0; methylmalonic acid, 516-05-2; parathyroid hormone, 12584-96-2, 68893-82-3, 9002-64-6; 25-hydroxyvitamin D, 64719-49-9; Calcium, Dietary; Homocysteine, 454-28-4; Methylmalonic Acid, 516-05-2; Parathyroid Hormone; Vitamin B 12, 68-19-9; Vitamin D, 1406-16-2