How do i take b12
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How to Take Vitamin B12: Methods and Recommendations
Vitamin B12, also known as cobalamin, is essential for various metabolic processes, including DNA synthesis, methylation, and mitochondrial function. Deficiency in this vitamin can lead to serious health issues such as megaloblastic anemia, cognitive decline, and neuropathy. This article explores the different methods of B12 supplementation and their effectiveness.
Dietary Intake of Vitamin B12
Natural vs. Synthetic B12
Vitamin B12 is naturally found in animal products, and dietary intake is generally the best way to maintain adequate levels. A study on rats showed that dietary B12 provides 35% more B12 to tissues compared to an equivalent single daily dose of synthetic B122. Natural B12 (hydroxo-B12) was also found to deliver 25% more B12 to the liver than synthetic B12 (cyano-B12)2. Therefore, consuming B12-rich foods like meat, fish, and dairy is highly recommended.
Oral Supplementation
Effectiveness of Oral B12
Oral B12 supplements are a convenient and effective way to address B12 deficiency. A comprehensive review of randomized controlled trials found that B12 supplementation significantly lowers homocysteine levels, especially when administered for longer durations and at higher doses5. Another study comparing oral and intramuscular administration found that oral B12 is a viable alternative, offering a simpler and cheaper option for treating B12 deficiency4.
Dosage Recommendations
For those with marginal B12 deficiency, sublingual B12 supplements are effective. A study comparing two sublingual dosages (350 µg/week vs. 2000 µg/week) found that both dosages were equally effective in improving B12 status and related metabolic markers3. This suggests that a lower daily dose (50 µg/day) can be just as effective as a higher weekly dose.
Intramuscular and Other Routes of Administration
Intramuscular Injections
Intramuscular injections are often used for severe B12 deficiency or when rapid correction is needed. A study protocol designed to compare oral and intramuscular B12 found that both methods are effective, but intramuscular injections may be preferred for immediate results4.
Alternative Methods
Emerging methods such as intranasal and transdermal administration are being explored to enhance B12 absorption. These methods could offer better patient compliance and cost savings, although more research is needed to confirm their effectiveness6 7.
Conclusion
Vitamin B12 can be effectively supplemented through various methods, including dietary intake, oral supplements, and intramuscular injections. For most people, consuming B12-rich foods or taking oral supplements is sufficient. However, for those with severe deficiencies or absorption issues, intramuscular injections or alternative methods like intranasal administration may be necessary. Always consult with a healthcare provider to determine the best supplementation method for your specific needs.
Sources and full results
Most relevant research papers on this topic
Combined biotin, folic acid, and vitamin B12 supplementation given during the transition period to dairy cows: Part I. Effects on lactation performance, energy and protein metabolism, and hormones.
Combined biotin, folic acid, and vitamin B12 supplementation during the transition period improves lactation performance, energy and protein metabolism, and hormones in dairy cows.
RCT
Rigorous JournalDietary Intake of Vitamin B12 is Better for Restoring a Low B12 Status Than a Daily High-Dose Vitamin Pill: An Experimental Study in Rats
Dietary intake of vitamin B12 is better for restoring a low B12 status than a daily high-dose vitamin pill.
RCT
Animal Study
Very Rigorous JournalEffect of two different sublingual dosages of vitamin B12 on cobalamin nutritional status in vegans and vegetarians with a marginal deficiency: A randomized controlled trial.
Sublingual dosages of 350 g/week (350 g/day) of vitamin B12 are more effective than 2000 g/week (one large oral dose) in improving vitamin B12 nutritional status in vegans and vegetarians with a marginal deficiency.
RCTVery Rigorous JournalOral versus intramuscular administration of vitamin B12 for the treatment of patients with vitamin B12 deficiency: a pragmatic, randomised, multicentre, non-inferiority clinical trial undertaken in the primary healthcare setting (Project OB12)
Oral vitamin B12 administration may be a cheaper and more effective alternative to intramuscular administration for patients 65 years of age with vitamin B12 deficiency.
RCT
Large Human TrialRigorous JournalA comprehensive review and meta-regression analysis of randomized controlled trials examining the impact of vitamin B12 supplementation on homocysteine levels.
B12 supplementation positively impacts lowering blood homocysteine levels, particularly when administered for longer periods and at larger doses.
Meta-AnalysisMethods to assess vitamin B12 bioavailability and technologies to enhance its absorption
The CobaSorb test and 14C-labeled B-12 test are the best available methods for assessing vitamin B12 bioavailability, while various technologies show potential for enhancing absorption, but evidence of effectiveness is limited.
Systematic ReviewInherited and acquired vitamin B12 deficiencies: Which administration route to choose for supplementation?
Sublingual, intranasal, and subcutaneous vitamin B12 administration routes offer better patient compliance and cost-savings compared to intramuscular and oral routes.
Literature ReviewVitamin B12 deficiency
Vitamin B12 deficiency affects individuals of all ages, particularly the elderly, and is caused by inadequate intake, bioavailability, or malabsorption, with management relying on B12 supplementation.
Highly CitedOral vitamin B12 supplement is delivered to the distal gut, altering the corrinoid profile and selectively depleting Bacteroides in C57BL/6 mice
Oral vitamin B12 supplementation increases active B12 in the distal gut and selectively depletes Bacteroides bacteria, but does not affect short-chain fatty acids or colitis susceptibility.
Non-RCTAnimal StudyVery Rigorous Journal