Why Are Vitamins Important for Your Brain?

Post by Meagan Marks

Nutrition and brain health

What you eat plays a crucial role in brain physiology and function and influences mood and mental health. Proper intake of micronutrients is vital for neurological and psychiatric well-being, with inadequate micronutrient levels potentially leading to problems with stress, hormone regulation, sleep, and overall cognitive function. 

What are vitamins?

Vitamins are essential organic compounds that our bodies need to function properly. The human body cannot make most vitamins on its own, so we must get them from our diet. When it comes to the brain, vitamins help maintain optimal psychiatric and neurological health by performing key functions: neurotransmitter synthesis, neuron growth, and neurochemical balance regulation. Particularly important, vitamins help protect against excitotoxicity, oxidative stress, and neuroinflammation – three main drivers of psychiatric and neurological disease.

Despite their importance, vitamin deficiencies are surprisingly common, particularly in the United States where the prevalent Western diet is highly processed and often lacking in micronutrients. In fact, it’s been suggested that this rise in micronutrient deficiency may be one factor related to the rise of mental and neurological disorders seen in the US.

So, which vitamins are indispensable for neurological functioning? How do they function in the brain? What risks come with deficiency, and what are some easily accessible food sources to add to your diet?

Vitamin A

Vitamin A is most known for its role in neurodevelopment and synaptic plasticity. It interacts with receptors in the brain that regulate the expression of genes that are involved in the formation of new neurons and neural connections. This is essential for learning, memory, and recovery from brain injuries. In addition, vitamin A also holds antioxidant properties that help protect the brain against oxidative stress and damage.

Adequate vitamin A levels are associated with better cognitive function, while deficiencies have been linked to cognitive impairments and increased risk of neurodegenerative disease. Food sources high in vitamin A include mangos, papayas, leafy vegetables, milk, eggs, and cheese. A note of caution, however: too much vitamin A (typically via oversupplementation) can be toxic!

B Vitamins

The B vitamins are a group of eight vitamins that perform some of the most essential and interconnected roles in the brain. B vitamins predominantly act as coenzymes, fusing with numerous proteins to boost their potential and help them perform more chemical reactions. Most notably, the B vitamins are responsible for synthesizing neurotransmitters and other signaling molecules in the brain.

Specific examples of their functions include:

B1 (thiamine) synthesizes precursors to neurotransmitters and other compounds essential to neuron function and structure. This includes acetylcholine, a neurotransmitter important to memory, learning, arousal, and attention.

B2 (riboflavin) acts as an antioxidant and helps regulate thyroid hormones that are essential to metabolism. B2 also helps to form B6, an extremely important B vitamin listed below.

B3 (niacin) also holds antioxidant properties, as well as helps with DNA metabolism and repair, cellular signaling, and oxidative reactions.

B5 (pantothenic acid) aids in neuron communication by myelinating axons and contributing to the structure of cells.

B6 is one of the most important vitamins to brain health. It is required to make the “feel good” neurotransmitters dopamine and serotonin, as well as the inhibitory neurotransmitter GABA. With even a mild B6 deficiency, levels of these neurotransmitters can drop in the brain. This leads to an excess of the excitatory neurotransmitter glutamate, which is linked to anxiety, depression, and excitotoxicity.

B8 (folic acid) and B12 are also both important to neurotransmitter synthesis, while B7 (biotin) is important for glucose metabolism.

Deficiencies in any of these vitamins will alter the brain’s ability to produce energy and perform essential processes, which can lead to chronic disease, psychiatric illness, and cognitive decline. Insufficient intake can manifest in many forms, including irritability, disordered sleep, inflammation, dementia, depression, and mental fog. Good sources of the B vitamins include fish, nuts, brown rice, pasta, citrus fruits, and leafy greens. 

Vitamin C

Vitamin C enhances neuron communication by myelinating axons, wrapping them in a protective, lipid-rich blanket. It also acts as a cofactor in producing dopamine and norepinephrine, neurotransmitters essential for motivation, mood, sleep, attention, and stress. Vitamin C is also a strong antioxidant, protects against excitotoxicity, and reduces inflammation by removing the proteins that cause it.

Deficiencies in vitamin C can lead to neuroinflammation, excitotoxicity, and oxidative stress, and may manifest as fatigue, mood swings, irritability, and depression. Great sources include bell peppers, citrus fruits, and various greens and vegetables.

Vitamin D

Vitamin D is well-known for managing fetal neurodevelopment and dopamine regulation. During pregnancy, vitamin D deficiency has been linked to abnormal neurodevelopment and is associated with an increased risk of schizophrenia and autism, which is thought to be due to impacts on dopamine regulation. Vitamin D supports the synthesis, transportation, and release of dopamine and is also positively correlated with growth and population of dopaminergic neurons.

Having a deficiency in vitamin D can increase the risk of cognitive decline, Alzheimer's disease, and Parkinson's disease and can greatly imbalance dopaminergic signaling. Great sources include fish, butter, cod liver oil, meat, milk, and eggs.

Vitamin E

Vitamin E is another vitamin that plays a strong protective role against oxidative stress, excitotoxicity, and neuroinflammation. Vitamin E can directly break down glutamate in the brain, reducing the risk of excitotoxicity and preventing cell damage. It also lowers levels of inflammatory proteins, reducing brain inflammation. Vitamin E also protects brain tissue by serving as an antioxidant.

Deficiencies may result in cognitive impairments, motor issues and muscle weakness. Good sources of vitamin E include seeds, nuts, avocados, sweet potatoes, and fish.

Vitamin K

While vitamin K is mostly known for its role in blood clotting and bone health, some emerging evidence suggests it also plays a role in brain function. Current findings suggest that it can reduce oxidative stress and neuroinflammation, help maintain cell membrane integrity, and support neuron survival and growth, but more research is needed to fully understand its role. Past studies have also shown that sufficient levels of vitamin K may improve cognitive performance and slow cognitive decline. 

Deficiencies may result in fatigue, irritability, and sleep disturbances, and great sources include leafy greens, vegetable oils, fruits, meat, eggs, and soybeans. 

What’s the takeaway?

Proper nutrition is essential to optimal neurological and psychiatric functioning. Consuming proper levels of micronutrients, whether through diet alone or with the help of supplementation under medical supervision, has been shown to 1) reduce stress, anxiety, and depression, 2) protect against inflammation, oxidative stress, and excitotoxicity, and 3) improve memory and cognitive tasks. While nutritional neuroscience is still a growing field, there is evidence that a proper and personalized diet could help prevent, manage, or even treat neurological and psychiatric disorders.

Access topic overview citations here: 1, 2, 3, 4, 5, 6, and 7.