Table 4.
Studies of vitamin B12 and risk of osteoporosis or fracture.
| Design and reference | Study Details | Main Outcome | Reduced risk |
|---|---|---|---|
| Cohort [84] | Elderly, fracture risk | Low vitamin B12 and/or HHcy: RR = 3.8 (95% CI:1.2, 1.6) males and 2.8 (95% CI:1.3, 5.7) females | Yes |
| Cohort [85] | Elderly, fracture risk | tHcy > 14, hip fracture HR = 1.49; (95% CI: 0.91, 2.46) | No |
| Cohort [86] | Hip fracture risk | fracture for high vs low tHcy (≥15 vs <9 µM), HR=2.42 (95% CI:1.43, 4.09) in women | Yes |
| Cohort [87] | Elderly, fracture risk | For 1 SD in tHcy fracture RR =1.4 (95% CI:1.2, 1.6) | Yes |
| Cohort [88] | Elderly BMD, tHcy, MTHFR polymorphisms | OR for low BMD w HHcy ≥15 µM vs. low tHcy OR=1.96 (95% CI:1.40, 2.75) for females. | Yes |
| Cohort [89] | Elderly BMD and plasma vitamins | Vitamin B12 <148 pM had lower BMD at hip (males) and spine (females) p < 0.05. | Yes |
| Cohort [90] | Elderly subjects (n=1550) | Serum vitamin B12 <15th percentile: OR of osteoporosis/osteopenia = 2.0 (95% CI:1.0, 3.9). | Yes |
| RCT [79] | 559 subjects:5 mg folate, 1.5 mg vitamin B12 or placebo | RR for hip fracture = 0.20 (95% CI: 0.08, 0.50) | Yes |
| RCT [78] | 47 Osteoporotic subjects 2.5 mg folate, 0.5 mg vitamin B12 and 25 mg B6 or placebo. | No changes in BMD or bone metabolism markers. | No |
| RCT [80] | Healthy older n = 276; folate 1 mg, vitamin B12 0.5 mg, B6 10 mg or placebo. | No differences in bone markers in vitamin vs placebo groups. | No |
| CT [81] | 5522 subjects with vascular disease, 2.5 mg folic acid, 50 mg B6, 1 mg vitamin B12 or placebo | HR =1.06 (95% CI:0.81, 1.40) for fracture risk in supplemented vs non supplemented | No |
HHcy = hyperhomocysteinaemia, tHcy = total homocysteine, CI = confidence intervals, SD = standard deviation, RR = relative risk, OR = odds ratio, HR = hazard ratio.