A randomized placebo controlled trial of vitamin B12 supplementation to prevent cognitive decline in older diabetic people with borderline low serum vitamin B12

Vegans are at an increased risk for certain micronutrient deficiencies, foremost of vitamin B12. Little is known about the short-term effects of dietary change to plant-based nutrition on vitamin B12 metabolism. Systemic biomarkers of vitamin B12 status, namely, serum vitamin B12 and holotranscobalamin, may respond quickly to a reduced intake of vitamin B12. To test this hypothesis, 53 healthy omnivore subjects were randomized to a controlled unsupplemented vegan diet (VD, n = 26) or meat-rich diet (MD, n = 27) for 4 weeks. Vitamin B12 status was examined by measurement of serum vitamin B12, holotranscobalamin (holo-TC), methylmalonic acid (MMA) and total plasma homocysteine (tHcy). Holo-TC decreased significantly in the VD compared to the MD group after four weeks of intervention, whereas metabolites MMA and tHcy were unaffected. Body weight remained stable in both groups. VD intervention led to a significant reduction of cholesterol intake, and adequate profiles of nutrient and micronutrient status. Lower intake of vitamin B12 was observed in VD, which was mirrored by a lower concentration of serum vitamin B12 and reduced holo-TC after 4 weeks. Plasma holo-TC may be a fast-responding biomarker to monitor adequate supply of vitamin B12 in plant-based individuals.

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118 Case series: subacute combined degeneration of the spinal cord in vitamin B12-replete recreational nitrous oxide abusers

Journal of Neurology Neurosurgery & Psychiatry ◽

10.1136/jnnp-2019-anzan.105 ◽

2019 ◽

Vol 90 (e7) ◽

pp. A38.2-A39

Author(s):

Chris Blair ◽

Chris Tremonti ◽

Leon Edwards ◽

Paul Haber ◽

Michael Halmagyi

Keyword(s):

Nitrous Oxide ◽

Vitamin B12 ◽

Prolonged Exposure ◽

Serum Vitamin ◽

Case Series ◽

The Body ◽

Enzymatic Reactions ◽

Full Time ◽

Central Demyelination ◽

Vitamin B12 Supplementation

IntroductionWithin a few years of its discovery in late 18th century, nitrous oxide was being used recreationally for its pleasurable effects. It remains in widespread use as an inhaled stimulant today, and can be legally acquired in bulk quantities with relative ease. In the body prolonged exposure to nitrous oxide leads to the oxidization of vitamin B12, rendering it unusable in key enzymatic reactions necessary for myelin synthesis. Over time this qualitative deficiency leads to a central demyelination syndrome that characteristically develops despite normal serum vitamin B12 levels and, with continued exposure to nitrous oxide, resists treatment with vitamin B12 supplementation.MethodNitrous oxide abusers presenting with a central demyelination syndrome were enrolled in this case series. Serum levels of vitamin B12, active B12, folate and homocysteine were measured. Nitrous oxide exposure was discontinued, and all patients were treated in accordance with evidence-based guidelines.ResultsEight patients presented with predominantly moderate-to-severe clinical deficits. The majority were vitamin B12 replete. In most cases individuals had actively engaged in prolonged vitamin B12 supplementation in an attempt to circumvent the harmful pathophysiology, of which they were loosely aware. Following treatment and rehabilitation several patients were discharged into full-time care, and most had significant residual disability at follow-up.ConclusionsThis case series not only illustrates the tragic consequences of abuse of this widely available and legally procured stimulant, but also highlights the futility of pursuing a nominally ‘protective’ strategy of vitamin B12 supplementation in the context of continued nitrous oxide exposure.

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Impact of baseline vitamin B12 status on the effect of vitamin B12 supplementation on neurologic function in older people: secondary analysis of data from the OPEN randomised controlled trial

European Journal of Clinical Nutrition ◽

10.1038/ejcn.2017.7 ◽

2017 ◽

Vol 71 (10) ◽

pp. 1166-1172 ◽

Cited By ~ 3

Author(s):

L M Miles ◽

E Allen ◽

R Clarke ◽

K Mills ◽

R Uauy ◽

...

Keyword(s):

Randomised Controlled Trial ◽

Older People ◽

Vitamin B12 ◽

Controlled Trial ◽

Secondary Analysis ◽

Neurologic Function ◽

Randomised Controlled ◽

Vitamin B12 Supplementation

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FALSE LOW SERUM VITAMIN B12 VALUES WITH RADIODILUTION ASSAYS USING BLOCKED R-BINDERS

The Lancet ◽

10.1016/s0140-6736(83)91939-6 ◽

1983 ◽

Vol 321 (8333) ◽

pp. 1104-1105 ◽

Cited By ~ 13

Author(s):

Jørn Brynskov ◽

Kjeld Andersen ◽

Peter Gimsing ◽

Erik Hippe

Keyword(s):

Vitamin B12 ◽

Serum Vitamin ◽

Low Serum

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Low Serum Vitamin B12 With Supplement In Pernicious Anemia

Blood ◽

10.1182/blood.v122.21.4722.4722 ◽

2013 ◽

Vol 122 (21) ◽

pp. 4722-4722

Author(s):

Ahmad Jajeh

Keyword(s):

Vitamin B12 ◽

Pernicious Anemia ◽

Serum Vitamin ◽

White Female ◽

Iron Supplement ◽

Cell Counts ◽

History Of ◽

Iv Iron ◽

Oral Supplement ◽

Low Serum

Pernicious anemia is commonly associated with autoimmune disorders. This abstract will describe three cases with low serum Vitamin B12 even with 2 weeks Vitamin B12 inrtamuscular injection of 1000 micrograms. First patient is thirty nine 39 years old white male with known history of pernicious anemia and Alopecia Totalis with prior history of Methotrexate and cyclosporin treatment. The patient had low serum iron and low iron saturation at initial presentation. He was given IV Iron supplement to saturate iron stores with good result. However, his serum vitamin B12 remain border line low normal below 300 pg/ml ( patient’s level is 210, normal range 180-941 pg/ml), even with every two weeks IM injection for more than six months. Patient was also given oral supplement with no increase in the serum vitamin B12 level. The second patient is sixty eight 68 years old white female with history of colon cancer that underwent resection and history of Hashimoto’s Thyroiditis who was on Thyroid hormonal supplement. Her serum Vitamin B12 level remain borderline low below 300. The third patient is forty 40 years old white female with history of Hypothyroidism and breast cancer that had received adjuvant chemotherapy post Lumpectoy and radiation therapy. This patient was treated with IV intravenous iron supplement for iron deficency with good result. All three patients had blocking antibodies to intrinsic factor and presented with various degree of iron deficency and treated with oral as well as IV iron supplement. Peripheral blood smear were reviewed on all the three patients. Hypersegmentation of neutrophils was seen with normocytic normochromic red cell morphology. One patient had low plateletes count. All patients had white blood cell counts below ten thousands. Two patients showed excess of apoptotic neutrophils. None of the patients had enlarged spleen or adenopathy or evidence of bone marrow hypofunction. All of the above patients improved clinically interm of sense of well being and increased level of energy with vitamin B12 supplement. None of the above patients had abnormal liver or kidney function. All patients had low serum vitamin B12 with one monthly dose IM injection plus oral supplement. All patients had normal LDH level and normal Folic acid level. In conclusion The low serum vitamin B12 levels with adequate supplement that should saturate the liver reserve open an interesting question about the possiblility of Transcobalamine receptor abnormality interm of abnormal function or deficency. Antibodies blocking the receptors or rapid neutrophils turn over is another possibility. Further study needed to solve this delema. Disclosures: No relevant conflicts of interest to declare.

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