Introduction
The development of the brain starts early in life and is a highly coordinated and complex process. The brain undergoes rapid growth and structural changes that take it from a simple tube structure (known as the neural tube) to the ridged and wrinkled, oval-like structure that is responsible for our cognitive abilities.
Not only is the brain the most metabolically active organ in the body, but during brain development, it grows rapidly. Therefore, nutrients like proteins, fat carbohydrates, and vitamins provide the essential building blocks, energy, and machinery for the brain to develop properly and to function throughout life.
Therefore, an absence of vitamins during this crucial period of development would be detrimental. And such situations have been shown to cause a range of serious issues ranging from mental retardation to blindness to death.1,3 Thus, much attention has turned to the exact neurochemical role of vitamins, the effect of their deficiencies, and the effect of supplementation. However, these topics have been of fierce debate (particularly supplementation) due to inconsistent findings, which we will explore later in this article. But first, let’s look at how the brain develops.
Understanding brain development
Prenatal development overview
The brain is densely populated by different types of cells that work together. The two most popular brain cells include neurons, of which there are 100 billion, and astrocytes, of which there are 1000 billion.4 A developed brain consists of highly interconnected networks of these brain cells. These networks allow it to process and transmit information, like a circuit board in a computer.
Brain cells are highly organized into different regions. Their positioning, development, and growth differ. For example, the brain regions do not develop their functions simultaneously.5
Postnatal development
Even though the general architecture of the brain is formed before birth, the brain continues to change throughout its lifetime, by refining the way its ‘biological circuit board’ is connected. This ability to change is known as ‘neuroplasticity’ and it is how our brain learns, remembers, and forgets things. Neuroplasticity can occur through establishing new connections, altering, or even dismantling existing connections among brain cells.6
However, not everything in the brain is ’plastic’. Some wiring is fixed during the prenatal period. This is why, for example, you can learn a language, new skills, and overcome mental illness, but once a baby’s brain has developed sight, it can’t learn to ‘see’ better.5 It is still up for debate, however on whether some traits are fixed or not.
Nevertheless, for the brain to learn from experience, numerous requirements must be met. The brain must be kept healthy and supplied with everything that it needs for growth, otherwise, its development and learning are impeded. This is because the brain requires nutrients to provide the energy for the growth and building of new connections as it develops and learns.
Brain development summary
In summary, prenatal development lays down the structural foundations of the brain and gets it organised into regions – a process largely controlled by genes. This provides the basic architecture the brain needs to sense and perceive information in its environment, so it can subsequently learn from experience during post-natal development, where it will physically modify its wiring as it learns.
Factors affecting brain development
The brain is a precious organ and many internal and external factors may influence its development, including:
- Disease
- Nutrition
- Genetics
- Exposure to drugs or toxins
- Stress
- Intellectual stimulation
- Emotional support
While prenatal development is largely under genetic control, the prenatal environment can still be highly influential as many of the factors mentioned above can influence brain development.7 Well-known illustrations of the foetus’ vulnerability during the prenatal period are the disastrous effects that maternal consumption of toxins such as drugs and alcohol, the underconsumption of nutrients such as folic acid, and head trauma can have on a baby’s cognitive development.5 Furthermore, even after the robust architecture of the brain has been laid down, other factors can also affect brain development during the postnatal period, including stress, sleep, and physical and emotional health.8
Essential vitamins for brain development
Overview
Vitamins are essential substances needed by the body in small amounts to support many of its reactions, such as energy production, metabolism, synthesis of essential molecules, and other reactions that allow the normal functioning of cells. These reactions, and the vitamins they require, are therefore crucial in maintaining the proper functioning and development of every system in the body.
Essential vs non-essential vitamins and their functions in the brain
Our bodies often fail to produce essential vitamins at all or in sufficient quantities, so we rely on our diet to provide them.
In total, there are 13 essential vitamins, and each serves specific functions in the body. There are four fat-soluble vitamins (A, D, E, and K) which can be stored in the body's fatty tissues, and nine water-soluble vitamins (B-complex vitamins and vitamin C) which are not stored and thus need to be replenished regularly through diet.
Non-essential vitamins can be synthesized by the body, but they are still essential in the functions they serve. Therefore, while they are in less need of regular replenishment in your diet, a deficiency in one of these may still cause disease.
Unfortunately, the functions of vitamins are poorly understood, especially when it comes to neurodevelopment. This is partly because they are involved in so many interrelated processes in the body that it makes it hard to study them in isolation. Many studies have instead focused on whether diseases are found more commonly in people lacking certain vitamins.
Effects of deficiency
When a person does not intake enough vitamins to satisfy their body’s needs, they are considered deficient. As vitamins have many fundamental roles in almost every body system, these systems will not work properly without them. Furthermore, as the development of the brain requires these body systems to work properly, such as normal cell functioning for cell growth, it follows that without adequate vitamins, body systems will not develop properly and likely lead to disease. A lack of essential vitamins and nutrition has been linked with many diseases, particularly in the children of pregnant mothers.
Some examples include:
- A lack of vitamin A intake during pregnancy has been linked with childhood blindness1
- A lack of vitamin B9 intake during pregnancy has been linked with neural tube defects9
- A lack of B12 intake in infants has been linked with a cluster of neurological problems, such as regression of developmental skills and neurological disability3
- A lack of vitamin D intake during early years has been linked with changes in brain structure and function, neurological and psychiatric disease10
As a result of the negative consequences of vitamin deficiency, the Committee on Medical Aspects of Food and Nutrition Policy (COMA) sets estimates for how much of each vitamin we require daily (RNI’s) and these are used to calculate the % of the recommended intake is of each vitamin in packages food (%NRV/%RI/%NV).
For guidance on the recommended intake of vitamins: British Nutrition Foundation.
Is there a need for supplementation?
Various surveys have shown that a considerable number of children take vitamin supplements, particularly among younger age groups. For instance, a British survey revealed that up to 32% of boys and 23% of girls under the age of 7 consumed supplements.11 Yet, some studies have shown that the intake of numerous vitamins at these ages in the UK is well above the reference nutrient intakes. Other UK-based studies have directly contradicted this by showing deficiencies in some of these vitamins, particularly vitamins C, D, folic acid, riboflavin, and thiamine.1
Several reasons may contribute to this contradiction between studies. For example, the prevalence of deficiency varies by age, geographical location, ethnicity, and income yet prevalence studies are often looking at a range of individuals that vary by more than one of these factors.1
Moreover, a particularly important factor is age. It seems obvious that as the prenatal brain is growing rapidly, it requires more nutrients, thus supplementation may be necessary. However, growing evidence is showing some vitamins are required in higher doses at certain developmental stages. Furthermore, some studies have shown that too much of some vitamins may also cause damage to a child in the womb.1
This conflicting data makes instructions on whether the general population could benefit from supplementation ambiguous. Ideally, recommendations need to be individualised. However, we do not have the resources or knowledge for individualised vitamin diets just yet.
It has also been suggested that, in developed countries, vitamin supplementation is probably not necessary for the general population (that has not been diagnosed with a clinical deficiency). This is largely informed by the clear availability of nutrients in these countries and the paucity of studies evidencing a biological sequence of events between the deficiencies and the disease they cause.
Furthermore, many of the aforementioned studies showing links between vitamin deficiencies and developmental problems, were conducted in developing countries where nutrient availability is often scarce and nutritional education lacking. In fact, it is advised that pregnant women in industrialised countries should aim to ensure that supplements are not causing overconsumption of particular vitamins, as this may also cause development issues. Therefore, pregnant women should be especially careful when using multivitamin supplements.1
Summary of unanswered questions
While research has shed light on the importance of vitamins for brain development, several important unanswered questions remain:
- What is the threshold for vitamin deficiency leading to developmental problems?
- At which developmental stages are individuals most susceptible to development issues from deficiencies?
- What are the specific roles of each vitamin in brain development and how do they interact with each other?
- For which groups of the population is vitamin supplementation required?
- How much of a health risk is associated with over-supplementation?
Due to these unanswered questions and the pace of scientific research, it is advisable to check the latest guidelines on nutritional requirements from medical professionals. Furthermore, if you are considering making any large changes to your diet, or are concerned about your or your child’s nutrition, speak to your doctor as they will be the most recently informed.
Tips for supporting brain development through nutrition
While nutrition is important, other factors should be taken into account for a combined approach to supporting brain development, including:
- Consumption of a balanced diet rich in fruits, vegetables, whole grains, lean proteins, and healthy fats
- Following prenatal care guidelines during pregnancy and taking any vitamin supplements prescribed by your doctor
- Limiting exposure to toxins and harmful substances during pregnancy, early childhood, and beyond
- Engagement in regular physical activity
- Getting recommended amounts of sleep, with a regular sleeping pattern
- Creating a stimulating and emotionally supportive environment
Summary
The initial stages of the brain's development, both inside and outside of the womb, are crucial. Many factors must be considered to ensure healthy development. Vitamins are especially important during early brain development as they ensure the proper working of fundamental building blocks and biological machinery required for growth.
Numerous studies show vitamin deficiencies during this critical period may lead to a spectrum of neurological consequences, spanning from mental retardation to psychiatric disorders. Of notable significance are essential vitamins like A, D, E, K, B-complex, and C, which appear to play a central role in maintaining optimal brain health, despite their exact function being unknown.
Furthermore, the brain still develops after this critical period through neuroplasticity and nutrition appears to influence this. However, it is not clear how much of an influence vitamins have at this period.
The question of whether supplementation is necessary remains a subject of ongoing discussion, especially in more industrialised countries. Moreover, research points to the importance of a comprehensive approach, encompassing balanced nutrition, toxin avoidance, physical activity, sufficient sleep, and a supportive environment, all of which are critical for fostering robust brain development.
References
- Benton D. Vitamins and neural and cognitive developmental outcomes in children. Proceedings of the Nutrition Society. 2011;71(1):14–26. doi:10.1017/s0029665111003247
- Nyaradi A, Li J, Hickling S, Foster J, Oddy WH. The role of nutrition in children’s neurocognitive development, from pregnancy through childhood. Frontiers in Human Neuroscience. 2013 Mar 26;7. doi:10.3389/fnhum.2013.00097
- Chalouhi C, Faesch S, Anthoine-Milhomme M-C, Fulla Y, Dulac O, Chéron G. Neurological consequences of vitamin B12 deficiency and its treatment. Pediatric Emergency Care. 2008 Aug;24(8):538–41. doi:10.1097/pec.0b013e318180ff32
- Herculano-Houzel S. The human brain in numbers: A linearly scaled-up primate brain. Frontiers in Human Neuroscience. 2009 Aug 9;3:3–31. doi:10.3389/neuro.09.031.2009
- Tierney AL, Nelson, III CA. Brain Development and the Role of Experience in the Early Years. Zero Three. 2009 Nov 1;30(2).
- Voss P, Thomas ME, Cisneros-Franco JM, de Villers-Sidani É. Dynamic Brains and the changing rules of neuroplasticity: Implications for learning and recovery. Frontiers in Psychology. 2017;8. doi:10.3389/fpsyg.2017.01657
- Doi M, Usui N, Shimada S. Prenatal environment and neurodevelopmental disorders. Frontiers in Endocrinology. 2022;13. doi:10.3389/fendo.2022.860110
- Ali S. A brief review of risk-factors for growth and developmental delay among preschool children in developing countries. Advanced Biomedical Research. 2013 Nov 30;2(1):91. doi:10.4103/2277-9175.122523
- Pitkin RM. Folate and neural tube defects. The American Journal of Clinical Nutrition. 2007;85(1). doi:10.1093/ajcn/85.1.285s
- Eyles DW, Burne THJ, McGrath JJ. Vitamin D, effects on brain development, adult brain function and the links between low levels of vitamin D and neuropsychiatric disease. Frontiers in Neuroendocrinology. 2013;34(1):47–64. doi:10.1016/j.yfrne.2012.07.001
- Smithers G, Gregory JR, Bates CJ, Prentice A, Jackson LV, Wenlock R. The National Diet and Nutrition Survey: Young People aged 4-18 years. Nutrition Bulletin. 2000;25(2):105–11. doi:10.1046/j.1467-3010.2000.00027.x