The Mental Health Benefits of B-Vitamins

We have reached the end of our well-being warrior series, finishing last (but not least) with the B-vitamins! So far, we have covered how vitamin D, omega-3, zinc, and magnesium are linked to our mental health and well-being, you can go back and check out those blogs for more details if you haven’t already. Today, we dive into the B-vitamins, taking a look at how they are linked to our mental wellness, the research supporting this, and where they can be found and optimized in our diet!

The Basics

B-vitamins are a group of eight essential nutrients that all work closely together in our body to perform roles in our cells functioning, as well as acting as keys for our enzymes to perform metabolic tasks1. Collectively, the actions of these vitamins are essential to our brain function, through creating energy, new genes, as well as generating the neurotransmitters needed for regulating mood, cellular signalling, and communication1.

The eight individual nutrients that create the “B-vitamins” may be familiar to you, they include thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), biotin (B7), folate/folic acid (B9), and cyanocobalamin (B12). While each of these nutrients have essential individualized tasks, three of them have received special attention for their mental health benefits, these are vitamins B6, B9, and B12. We will discuss these in more detail below. 

The Link to Mental Health

The brain is the most metabolically active organ in the human body, accounting for over 20% of our body’s energy use, while only taking up 2% of body weight1. Seeing as the brain needs ample energy to stay functional, and that B-vitamins are essential for creating this energy, it is unsurprising that deficiencies can lead to an impairment in normal brain functions.

A 2019 systematic review of relevant literature aimed to answer the question of whether or not supplementing with B-vitamins has an effect on mood, comparing the results of “healthy individuals” to those identified to be “at-risk”2. They found that majority of the studies reported a positive effect on the overall facet of mood, with a significant benefit for those undergoing stress. While they were unable to find a clinically significant link to depression or anxiety, other studies have been able to uncover this relationship. One study, which consisted of a 17-year follow-up, reported that adolescence with lower intakes of B-vitamins were more likely to experience mental health problems3. This link is supportive of the fact that individuals with poor nutrition are more likely to experience mental illness4. The systematic review mentioned above concluded that B-vitamins may be used to benefit mood status in “healthy”, as well as “at-risk” populations.

In addition to B-vitamins being essential for normal brain functioning, there is another theory that sheds light on the relationship between B-vitamins and our mental health. This theory is the “homocysteine hypothesis”1, which involves vitamins B6, B9, and B12. Homocysteine is a by-product of protein metabolism; in a healthily functioning body it is recycled out of our system in order to keep the levels in our blood regulated. The three B-vitamins mentioned above are closely involved in the recycling of this by-product, therefore, if our bodies are deficient in these nutrients the process of regulating homocysteine levels can be impacted. If this occurs, homocysteine levels in our blood can rise, leading to potentially detrimental effects for brain health. The theoretical mechanisms proposed for how elevated homocysteine levels effect brain function include increasing oxidative stress, inhibiting necessary cellular processes, damaging our genes, and being potentially toxic to our cells1

A recent small study5 aimed to validate this hypothesis, by administering a supplement of B6, B9, and B12, as well as a placebo, to patients experiencing a first-episode psychosis. Patients were then monitored for their homocysteine levels and behavioural attributes. The researchers found that those given the B-vitamin supplementation had lower homocysteine levels, as well as increases in their mental stability, compared to those receiving the placebo who reportedly had worsening symptoms.

Where Can We Get it, and How Much Do We Need?

B-vitamins can be found fairly ubiquitously in the food chain, in both animal products, plant sources, as well as naturally and through the fortification of grains. Ensuring your diet is well balanced and optimized with a variety of different protein sources, fruits and vegetables of different colours, and whole grains will help to ensure you are getting all the B-vitamins that you need. As such, deficiency in many of the B-vitamins is rare. This rarity is made true since, as mentioned above, there is now a fortification process which adds many of the B-vitamins into commonly consumed foods such as certain breakfast cereals and grains.

However, one B-vitamin requires special attention since it is naturally only present in animal products and its absorption can be impacted by several different aspects of our health. This is vitamin B12, and there are several populations which would benefit from supplementation. These include, but may not be limited to, plant-based eaters, people with GI disturbances, older adults, and those with pernicious anemia6. Since B12 is naturally only found in animal products, it is always recommended that plant-based eaters supplement with this nutrient. Those struggling with GI complications, including Crohn’s disease, celiac disease, or surgeries, may be unable to absorb adequate amounts of this nutrient from their food, calling for a supplement. Older adults and those diagnosed with pernicious anemia may also benefit from supplementation, seeing as humans require a special co-factor to absorb B12, called intrinsic factor, which naturally declines as we age and is not present in those with this type of anemia. Since intrinsic factor attaches to B12 in the GI tract, intramuscular B12 supplementation may actually be more appropriate for these populations. Speak to your physician about this option if you want more information on how to receive this supplement.

Vitamin B12 is found most abundantly in seafood, red meat, and dairy products6, so for those who consume these items on a daily basis you are most likely in the clear. However, if you belong to one of the populations listed above and supplementation is recommended for you, know that it is a completely safe option, unless otherwise indicated by your physician. All of the B-vitamins are water soluble, which means if we consume more than our required amount on a daily basis it will just be passed through our body in our urine. B12 can be found in most multivitamins, in a B-complex, or alone in a tablet form, making it very accessible and easy to find!

Another thing to keep in mind when thinking about B-vitamins, is that if you struggle to eat a balanced diet with a variety of protein sources, coloured produce, and whole grains, you too may benefit from a supplement. A B-complex may be beneficial in this case, since it offers a source of all the essential B-vitamins!

The Bottom Line

There is no doubt that B-vitamins are absolutely essential for normal brain functioning and processing. As such, ensuring your diet is balanced and varied to optimize your nutrient intake, and/or supplemented with B-vitamins, is a recommended way to boost your mental health with nutrition.

If you have any questions about B-vitamins, or any of the well-being warriors covered in this series, reach out to Healthy Essentials Clinic and a dietitian would be more than happy to meet with you and discuss individualized ways to optimize your diet to increase your mental health and well-being!


1Kennedy D. O. (2016). B Vitamins and the brain: mechanisms, dose and efficacy – a review. Nutrients8(2), 68. Received from:

2Young, L. M., Pipingas, A., White, D. J., Gauci, S., & Scholey, A. (2019). A systematic review and meta-analysis of B vitamin supplementation on depressive symptoms, anxiety, and stress: effects on healthy and ‘at-risk’ individuals. Nutrients11(9), 2232. Received from:

3Herbison, C. E., Hickling, S., Allen, K. L., O’Sullivan, T. A., Robinson, M., Bremner, A. P., Huang, R., Beilin, L. J., Mori, T. A., & Oddy, W. H. (2012). Low intake of B-vitamins is associated with poor adolescent mental health and behaviour. Preventive Medicine, 55(6), 634-638. Received from:

4Rao, T. S., Asha, M. R., Ramesh, B. N., & Rao, K. S. (2008). Understanding nutrition, depression and mental illnesses. Indian journal of psychiatry50(2), 77–82. Received from:

5Allott, K., McGorry, P. D., Yuen, H. P., Papas, A., Stephens, T. C. B., & O-Donnell, C. P. (2019). The vitamins in psychosis study: a randomized, double-blind, placebo-controlled trial of the effects of vitamins B12, B6, and Folic Acid on symptoms and neurocognition in first-episode psychosis. Biological Psychiatry, 86(1), 35-44. Received from:

6National Institutes of Health. (2020). Vitamin B12: fact sheet for health professionals. Received from: of B-Vitamins