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by PRL Staff, May, 2023


Vitamins are organic compounds considered essential for normal physiological functioning but are not made endogenously by the body. Every single day, a variety of essential nutrients must be extracted and utilized from the diet. Healthy human bodies require adequate amounts of 13 vitamins; four fat-soluble vitamins (A, D, E, K) and nine water-soluble vitamins, which includes vitamin C and the eight B vitamins: thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), folate (B9), and vitamin B12. Despite being grouped together, B vitamins have no chemical structure similarity but instead, set themselves apart by their water solubility and the inter-related, co-enzyme functions they facilitate.

Synergistically B-vitamins have a vital role in cell function and act as co-enzymes in numerous catabolic and anabolic enzyme reactions. Evidence suggests that adequate amounts of EACH of the eight water-soluble b-vitamins are essential for optimal physiological and neurological functioning. B-vitamins are involved in energy production, DNA/RNA synthesis/repair, genomic and nongenomic methylation, and are crucial for the synthesis of numerous neurochemicals, signaling molecules, and ultimately, neurotransmitter adaptability.

Furthermore, brain adaptability, or neuroplasticity, is a crucial concept that highlights the brain’s ability to change and adapt in response to new experiences and environments. B-vitamins have been shown to promote brain adaptability, which is critical for learning, memory, and overall cognitive function.


Accounting for more than 20% of the body’s total energy expenditure, the brain is the most metabolically active organ of the body. The importance of B-vitamins as fuel for the brain is evident by the fact that each B vitamin is actively transported across the blood-brain barrier via dedicated transport mechanisms. Levels of these essential B-vitamins are tightly regulated by mechanisms responsible for maintaining homeostasis, resulting in lower concentrations of B-vitamins in the blood, and higher concentrations in the brain. Many of the B-vitamins directly or indirectly influence brain health and function.

Regarding neurological disorders, evidence reveals that deficiencies in key B-vitamins may be at the root of neurological disorders, psychiatric diseases, and dementia. For example, insufficient amounts of B6 are associated with depressed mood, irritability, suboptimal cognitive performance, and poor mental health. A deficiency of B12 manifests as neurological impairment initially and can result in pernicious anemia when there has been an extended period of B12 deficiency.

Epidemiological evidence reveals that B-vitamin deficiencies are prevalent worldwide, including developed countries. In the absence of an optimal diet, supplementing with the entire array of B-vitamins, in therapeutic doses, may be a rational approach for preserving brain health. However, with an over-emphasis on examining what B-vitamin deficiencies look like and how to meet the minimum daily requirements, there is no clear understanding of what optimal B-vitamin status would look like and if it may be associated with healthy ageing and maintaining healthy brain function.


The nervous system is dependent upon many of the B-vitamins, but B1, B6, and B12 are of particular importance when it relates to maintaining a healthy nervous system. 

All three B-vitamins have been found to be effective at improving certain neurological conditions without a deficiency and seem to have a synergistic relationship as each holds a different role that cannot be replaced by either of the others.

Vitamin B1 provides an energy source to nerve cells and also acts as an antioxidant to help relieve oxidative stress while B6 is a key part of the synthesis of neurotransmitters like GABA, dopamine, and serotonin.

Taking cobalamin’s brain-specific role a step further than outlined above, it also works to regenerate myelin to protect the nervous system and ensure proper functioning.

The combination of B1, B6, and B12 protects normal neurological functions and particularly impacts the peripheral nervous system.

Two of these essential B-vitamins also play a prominent role in decreasing homocysteine levels.


Homocysteine cannot be recycled without adequate levels of B-vitamins, especially B6, folate and B12. When diets are not delivering essential nutrients to fuel cellular energy production, metabolic processes become inefficient, and cells may not be optimally nourished.

The “homocysteine hypothesis” is the predominant mechanistic theory behind the complex inter-relationships among B-vitamins. This theory proposes that high serum homocysteine levels not only signal the body that essential B-vitamins are in short supply, but moreover, may be an independent predictor of cardiovascular disease and cognitive decline.

Homocysteine appears to increase oxidative stress, inhibit methylation reactions, increase mitochondrial dysfunction, damage DNA dysregulating its repair, and can also cause neurotoxicity, directly and indirectly, causing fatal damage to neurons/brain cells. This ultimately results in the accumulation of beta-amyloid plaques, brain atrophy, and compromised cerebrovascular circulation. Research has predominately focused only on these 3 b-vitamins, regardless of the complex, interconnected nature of all B-vitamins for energy metabolism. For example, riboflavin is also an essential but overlooked nutrient for the metabolism of homocysteine as a cofactor for the MTHFR enzyme. Low levels of riboflavin are correlated to higher homocysteine levels as well as higher blood pressure in those individuals with the MTHFR polymorphism. Polymorphisms of genes involved in the absorption, metabolism, and function of B-vitamins have been linked to a higher occurrence of psychiatric and cognitive disorders.

It is suggested that 40% of the population suffers from a genetic mutation compromising the proper conversion of unmethylated B-vitamins. Without proper methyl transfer for homocysteine modulation, the necessary formation of methyl donors involved in cardiovascular, neurological, reproductive and detoxification functions cannot be adequately produced. Individuals most likely to benefit from B-vitamin supplementation have higher baseline homocysteine levels which linked to cognitive deficits in subpopulations with a higher incidence of depression, schizophrenia, and dementia.

Given the synergy involved between B-vitamins and energy metabolism, B-vitamin supplementation, it is generally recommended to supplement with the whole vitamin B-complex family, in addition to isolated Bs (such as B12, folate, B6 or Biotin) that may already be a part of personal supplement protocols. Vitamin B supplementation needs to be delivered in their biologically active blood circulating forms. The whole B-vitamin family is needed to help keep the body in balance and harmony for greater physical, emotional, and mental health. Especially during times of high emotional or physical stress, as well as phases of life that require greater physical and/or mental stamina, supplementing with B-vitamins may improve energy levels, neurotransmitter adaptability, and ultimately quality of life.


Aside from diet and genetics, levels of B-vitamins in the body are affected by numerous factors including age and environment. A deficiency in B-vitamins is associated with several neurological conditions including depression, anxiety, dementia, and Alzheimer’s disease. Not only are B-vitamins important for brain function but several clinical studies indicate that they have a beneficial role in mood stabilization and stress management. Additionally, the influence of diet on brain health has been considered a modifiable risk factor to prevent mood disorders. Up to 30% of patients diagnosed with depression have elevated homocysteine levels. According to meta-analysis and systematic review of B-vitamin supplementation on depressive symptoms, anxiety, and stress, nutritional interventions designed to improve diet quality are associated with a reduction in depressive symptoms, independent of self-assurance and physical activity levels. To prevent deficiency-related disorders, it is important to optimize mood and well-being for all individuals. This includes optimal nourishment, quiet self-reflection and meditation, compassionate counseling, and bodywork such as Emotional Freedom Technique (EFT) or massage therapy.

As a wellness practitioner, it is imperative to have a holistic approach to dietary supplementation with B-vitamins. Due to the complex, interconnected nature of B-vitamin absorption, metabolism and function, all B-vitamins should be considered for supplementation before limiting protocols to vitamins B6, B12 and folate, the three most extensively studied B-vitamins. It is important to note that folate supplementation can mask B12 deficiency, which can be highly problematic in the long run as far as brain health goes. Additionally, utilizing the ‘activated’ forms of B-vitamins, obtained via natural fermentation methods, are the most bioavailable and are most beneficial for strict vegetarians or vegans, those having absorption or digestive issues, elderly populations, those who consume the SAD, inherently high in refined or processed foods, as well as those who have the MTHFR polymorphisms. Now more than ever, high quality, activated B-vitamin supplements are an essential ally to mind, mood, and memory and furthermore, build optimal health!


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