Meta-analysis of B vitamin supplementation on plasma homocysteine, cardiovascular and all-cause mortality

Elevated plasma homocysteine (Hcy) concentrations have been implicated with risk of cognitive impairment and dementia, but it is unclear whether low vitamin B12 or folate status is responsible for cognitive decline. Most studies reporting associations between cognitive function and Hcy or B-vitamins have used a cross-sectional or case–control design and have been unable to exclude the possibility that such associations are a result of the disease rather than being causal. The Hcy hypothesis of dementia has attracted considerable interest, as Hcy can be easily lowered by folic acid and vitamin B12, raising the prospect that B-vitamin supplementation could lower the risk of dementia. While some trials assessing effects on cognitive function have used folic acid alone, vitamin B12 alone or a combination, few trials have included a sufficient number of participants to provide reliable evidence. An individual-patient-data meta-analysis of all randomised trials of the effects on cognitive function and vascular risk of lowering Hcy with B-vitamins will maximise the power to assess the epidemiologically-predicted differences in risk. Among the twelve large randomised Hcy-lowering trials for prevention of vascular disease, data should be available on about 30 000 participants with cognitive function. The principal investigators of such trials have agreed to combine individual-participant data from their trials after their separate publication.

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One year B-vitamins increases serum and whole blood folate forms and lowers plasma homocysteine in older Germans

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm-2014-0540 ◽

2015 ◽

Vol 53 (3) ◽

Cited By ~ 4

Author(s):

Susanne H. Kirsch ◽

Wolfgang Herrmann ◽

Vera Kruse ◽

Rudolf Eckert ◽

Stefan Gräber ◽

...

Keyword(s):

Vitamin D ◽

Whole Blood ◽

Baseline Level ◽

Plasma Homocysteine ◽

B Vitamins ◽

Vitamin Supplementation ◽

Baseline Serum ◽

One Year ◽

B Vitamin

AbstractWe aimed to study the effect of long-term supplementation of B-vitamins on folate forms in serum and whole blood (WB) in elderly German subjects.59 participants (mean age 67 years) were randomized to daily receive either vitamin DB-vitamins supplementation for 6 months led to higher concentrations of 5-methyltetrahydrofolate (5-methylTHF) in serum (mean 49.1 vs. 19.6 nmol/L) and WB (1332 vs. 616 nmol/L). Also non-methyl-folate concentrations in serum and WB were higher after 6 months with B-vitamins supplementation. Unmetabolized folic acid (UFA) increased after supplementation. tHcy concentration was lowered after 1 year of B-vitamin supplementation (mean 13.1 vs. 9.6 μmol/L). A stronger reduction of tHcy after 1 year was found in participants who had baseline level >12.5 μmol/L (mean 17.0 vs. 11.9 μmol/L) compared to those with baseline tHcy lower than this limit (mean 9.1 vs. 7.4 μmol/L). In contrast, the increases in serum and WB 5-methylTHF were comparable between the two groups.One year B-vitamins supplementation increased the levels of 5-methylTHF and non-methyl-folate in serum and WB, normalized tHcy, but caused an increase in the number of cases with detectable UFA in serum. Lowering of tHcy was predicted by baseline tHcy, but not by baseline serum or WB 5-methylTHF.

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A Systematic Review and Meta-Analysis of B Vitamin Supplementation on Depressive Symptoms, Anxiety, and Stress: Effects on Healthy and ‘At-Risk’ Individuals

Nutrients ◽

10.3390/nu11092232 ◽

2019 ◽

Vol 11 (9) ◽

pp. 2232 ◽

Cited By ~ 10

Author(s):

Lauren M Young ◽

Andrew Pipingas ◽

David J White ◽

Sarah Gauci ◽

Andrew Scholey

Keyword(s):

Systematic Review ◽

At Risk ◽

Depressive Symptoms ◽

Meta Analysis ◽

Nutrient Status ◽

Vitamin Supplementation ◽

Random Effects Models ◽

At Risk Populations ◽

Randomised Controlled ◽

B Vitamin

A systematic review and meta-analysis was undertaken to examine and quantify the effects of B vitamin supplementation on mood in both healthy and ‘at-risk’ populations. A systematic search identified all available randomised controlled trials (RCTs) of daily supplementation with ≥3 B group vitamins with an intervention period of at least four weeks. Random effects models for a standardized mean difference were used to test for overall effect. Heterogeneity was tested using the I2 statistic. Eighteen articles (16 trials, 2015 participants) were included, of which 12 were eligible for meta-analysis. Eleven of the 18 articles reported a positive effect for B vitamins over a placebo for overall mood or a facet of mood. Of the eight studies in ‘at-risk’ cohorts, five found a significant benefit to mood. Regarding individual facets of mood, B vitamin supplementation benefited stress (n = 958, SMD = 0.23, 95% CI = 0.02, 0.45, p = 0.03). A benefit to depressive symptoms did not reach significance (n = 568, SMD = 0.15, 95% CI = −0.01, 0.32, p = 0.07), and there was no effect on anxiety (n = 562, SMD = 0.03, 95% CI = −0.13, 0.20, p = 0.71). The review provides evidence for the benefit of B vitamin supplementation in healthy and at-risk populations for stress, but not for depressive symptoms or anxiety. B vitamin supplementation may particularly benefit populations who are at risk due to (1) poor nutrient status or (2) poor mood status.

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