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ARS Home » Pacific West Area » Davis, California » Western Human Nutrition Research Center » Obesity and Metabolism Research » Research » Publications at this Location » Publication #312227

Research Project: Improving Public Health by Understanding Diversity in Diet, Body, and Brain Interactions

Location: Obesity and Metabolism Research

Title: Vitamin B-12 treatment of asymptomatic, deficient, elderly Chileans improves conductivity in myelinated periphreal nerves, but high serum folate impairs vitamin B-12 status response assessed by the combined indicator of..

Author
item Brito, Alex - University Of California
item Miller, Joshua - Rutgers University
item Green, Ralph - University Of California
item Fedosov, Sergey - Aarhus University
item Harvey, Danielle - University Of California
item Shahab-ferdows, Setti
item Verdugo, Renato - University Of Chile
item Sanchez, Hugo - University Of Chile
item Albala, Cecilia - University Of Chile
item Uauay, Ricardo - University Of Chile
item Allen, Lindsay

Submitted to: American Journal of Clinical Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/14/2015
Publication Date: 1/20/2016
Citation: Brito, A., Miller, J.W., Green, R., Fedosov, S.N., Harvey, D., Shahab-Ferdows, S., Verdugo, R., Sanchez, H., Albala, C., Uauay, R., Allen, L.H. 2016. Vitamin B-12 treatment of asymptomatic, deficient, elderly Chileans improves conductivity in myelinated periphreal nerves, but high serum folate impairs vitamin B-12 status response assessed by the combined indicator of vitamin B-12 status. American Journal of Clinical Nutrition. 103:250-257. doi: 10.3945/ajcn.115.116509.

Interpretive Summary:

Technical Abstract: Since 2005 the National Feeding Program for the Elderly (PACAM) in Chile has provided a B12 fortified milk drink (1.7 µg B12/d) which is insufficient to ensure B12 adequacy in many individuals. The objective was to evaluate effects of adding 1 mg B12/d to PACAM vs 1 mg B12/d as a pill with PACAM on B12 status and neurophysiological function in Chilean elderly. The cluster RCT had 3 arms: fortified PACAM (1 mg B12, n=101), pill with PACAM (1 mg B12, n=97) and placebo with PACAM (control, 1.7 ug B12, n=89). B12 status was defined as cB12, which combines serum B12, holoTC, MMA and tHcy. cB12 and peripheral sensory and motor nerve conduction were assessed at baseline and after 4 (efficacy), 9 and 18 mo (effectiveness). A linear mixed-effect model was performed. Based on cB12, 7.6% of elderly were B12 deficient and 27.3% had low status at screening. Subjects with very low serum B12 were excluded and treated. cB12 correlated more strongly (-~0.40, p<0.0001) with the average distal latency of the sural nerve at baseline than did any individual B12 marker. cB12 did not differ among groups at baseline. After 4 mo, B12 provided by PACAM or a pill equally (p<0.0001) improved B12 status. The effect was maintained at 9 and 18 mo. Sensory nerve conduction latencies of the sural nerves were reduced (p<0.0001) after 4 mo in both supplement groups. Giving elderly B12 fortified milk was as effective and efficacious as B12 in pills for improving B12 status and peripheral nerve conduction, and cB12 was the best biomarker of status and function. Chilean FONDECYT #1070592 and USDA, ARS WHNRC