A vitamin B-12 supplement of /d for eight weeks does not normalize urinary methylmalonic acid or other biomarkers of vitamin B-12 status in elderly people with moderately poor vitamin B-12 status.

What Was Tested

This randomized controlled trial looks at Vitamin B 12 and Smoking.

A study was conducted to investigate the responsiveness of uMMA to supplemental vitamin B-12 in comparison with other biomarkers of vitamin B-12 status [plasma vitamin B-12, serum holotranscobalamin (holoTC), plasma MMA] in elderly people with moderately poor vitamin B-12 status.

Why It Was Studied

Plasma vitamin B-12 is the most commonly used biomarker of vitamin B-12 status, but the predictive value for low vitamin B-12 status is poor.

The urinary methylmalonic acid (uMMA) concentration has potential as a functional biomarker of vitamin B-12 status, but the response to supplemental vitamin B-12 is uncertain.

Who Took Part

The abstract describes 100 people taking part.

PubMed indexes the participants as older adults and people over 80, both men and women.

How the Study Was Run

The researchers set it up as a randomized, double-blind and placebo-controlled study.

Random assignment meant chance, not the researchers, decided who got Vitamin B 12 and who got the comparison, which limits bias.

As a double-blind Vitamin B 12 study, the assignments were hidden from both participants and investigators until the end.

The comparison arm used a placebo, so changes seen with Vitamin B 12 could be set against what happens without it.

What Was Measured

The subject headings attached to it are Aging, Apoproteins, Biomarkers, Creatinine, Cross-Sectional Studies, Dietary Supplements and Methylmalonic Acid.

What This Means in Plain Language

The paper is a randomized, double-blind and placebo-controlled study of Vitamin B 12 and Smoking in 100 people.

The publication is from 2013 (The Journal of nutrition), a journal based in United States.

More context: all human trials.