Vitamin B12

Last updated: March 21, 2017


Within certain health circles it is trendy to take “B-shots”, which are primarily comprised of vitamin B12 (also known as cobalamin). The efficacy of these shots vary widely depending on the source, but vitamin B12 is an essential nutrient with far-reaching cognitive implications.

Most notably, studies have shown that vitamin B12 aids in neuroprotection by reducing neurotoxicity [1]. For elderly individuals, it is even more important for preventing cognitive decline and neurodegenerative diseases [2]. Other benefits include memory benefits, concentration, and executive function [3].

Almost all of these benefits (and a host of others) come from vitamin B12’s role in the process known as “methylation”, which impacts all aspects of our brain and body [4].

Also Known As

Cyanocobalamin, cobalamin, methylcobalamin, 5-deoxyadenosylcobalamin, adenosylcobalamin, cobamamide, dibencozide, hydroxocobalamin

Editors’ Thoughts on Vitamin B12

This is one of the most popular B-vitamins and definitely the option I would suggest the most. I don’t believe most people are deficient in vitamin B12 per se, but it seems this has the most positive effect on enhancing cognitive performance as opposed to merely helping in the case of deficiency.

I don’t take vitamin B12 (or any b-vitamins for that matter) regularly, but I get large doses a couple of times per week when I take Qualia, (which has a dosage of 16,667% daily recommended value). Also, I notice many old people that I know take b-vitamins (including my grandparents).

Mansal Denton, Nootropedia Editor

vitamin b12

Benefits of Vitamin B12

For the elderly and vegans, supplementing vitamin B12 is almost essential and highly beneficial. According to research, only 23% of adults aged 19 – 64 are deficient in this essential vitamin [5], but that number jumps to 62% for those above 65 years old [6].

There are mood benefits of vitamin B12 for those who suffer from depression or generalized anxiety [7]. One study showed that people with mid to severe depression had 17 – 27% less vitamin B12 than their healthy counterparts [8]. S-adenosylmethionine exerts an antidepressant effect and theories suggest vitamin B12 upregulates production of this molecule [9].

While vitamin B12 alone may not be enough to resolve depression or anxiety, those who have specific genetic mutations (such as MTHFR) might be utilizing vitamin B12 poorly and thus causing poor health consequences.

Aside from the mood advantages, there are plenty of neuroprotective benefits of vitamin B12. Elderly people see protective effects against cognitive decline and neurodegenerative diseases according to a 2009 publication in The American Journal of Clinical Nutrition [10].

Because of the vitamin’s role as a cofactor for numerous enzymes, additional B12 can help support neuron regeneration while at the same time preventing neurotoxicity [11].

Side Effects of Vitamin B12

There are few side effects of vitamin B12 minus potential gastrointestinal distress. However, as mentioned earlier, doses up to 16,000% of the daily recommended intake have a negligible effect on most people.

There are side effects of vitamin B12 combined with other ingredients, unfortunately. These are considered nutrient interactions and one of the main issues is with folate. Many people who supplement folate will mask a deficiency with vitamin B12 [12], which creates an increased risk especially for elderly and vegans.

Vitamin B12 Dosage

The daily recommended vitamin B12 dosage is 1000 mcg (1 mg) in supplemental form. Most meat products contain adequate supplies of vitamin B12, but supplementation is helpful for many. High doses of vitamin B12 are well-tolerated in most people.

How and Where to Buy Vitamin B12

Even though vitamin B12 is a popular and ubiquitous health supplement, the source of this ingredient matters. While you can purchase vitamin B12 at local grocery or health food stores, it is probably best that you find an online retailer for the right type.

The best source of vitamin B12 is in the form of methylcobalamin. There are many methylcobalamin products for sale online, but ensure you purchase from a reputable vendor. We recommend this vendor for your vitamin B12 methylcobalamin.

Selected Community Experiences

I took a sub-lingual Jarrow 5000 Methyl B-12 supplement, and felt more energetic and felt a dull sensation on my forhead.” [13] – ThirdHuman

I just found out I have been taking 33,000% of the daily recommended value of B-12 (Methylcobalamin) for the past 7 months almost every day. I feel tired, dehydrated all the time no matter how many liters of water I drink a day, anxious, and weaker than I was before taking the B-complex vitamin supplement…Another reason I started the vitamin B-12 complex vitamin was because I had a concussion 7 months ago and was extremely drowsy and tired for about a month straight, the B-12 helped give me energy I needed to finish college.” [14] – DissoPsycheNautMXVII

References (Click to Expand)
  1. //
  2. //
  3. //
  4. //
  5. //
  6. //
  7. //
  8. //
  9. //
  10. //
  11. //
  12. //
  13. //
  14. //


Nootropedia provides research-driven and accessible nootropics information. Don’t be in the dark about nootropics.