Introduction

The infancy (0-3) lifestage is a time of rapid transition, growth and change, particularly for developing infant’s brains.

Infant Brain Development

From the moment a child is born it should have all the cells in its brain that it will ever need (around 100 billion cells), although new brain cells can still be created into adulthood. Synapses, which faciliate the ability for the brain to send and receive information, are formed far quicker compared during these first three years of life to other stages of growth.

The cerebral cortex, the most outer layer of brain tissue, has developed a great amount and overridden duties previously carried out by the more primitive brainstem. Within the first year of life, the cerebellum, involved with memory and movement, can triple in size to account for all the visual and physical experiences the infant encounters. Moreover, within the first three years of life the weight of the brain triples, as it undergoes profound growth. This growth is focused on the prefrontal cortex, the area of the brain associated with decision making, awareness and even aspects of personality. This area becomes incredibly dense with synaptic connections that by age 3, the prefrontal cortex is fully developed in terms of synaptic density. During these first three years of life, intense neurobiological growth . Ketones, water-soluble molecules produced from fatty acids and used for energy, are an infant’s primary fuel in the developing brain during this time. This is important because some novel research has shown that utilising exogenous ketones, or inducing ketosis via diet in middle age, could be a potential method in preventing the onset or progression of neurodegenerative diseases, such as dementia.   

Risk Factors and Barriers to Change

Poverty
Humans have one of the fastest brain growth rates compared to other animals, the neonatal brain uses 60% of the body’s oxygen and requires many calories . Unfortunately, not all pregnant individuals have equal access to nutritionally dense foods and a hygienic environment. Research has shown that people of colour and individuals from ethnic minority groups are particularly vulnerable. Even if successful births occur in impoverished environments, the infant still requires special nutritional attention to continue their cognitive development. In the UK, pregnant individuals and families who meet eligibility criteria may be able to claim certain foods and supplements via the NHS Healthy Start scheme. This scheme may increase access for at risk individuals and families to fresh and infant milk, vegetables and fruit, pulses, pregnancy and breastfeeding multivitamin and mineral complexes, and vitamin drops for newborns and children. Presently, more large scale research is required to investigate sustainable and empowering strategies and means to support families who have difficulties and barriers to accessing nutritious foods and supplements around the world. 

Nutritional Strategies

Vitamins A, C and D

Vitamin D is crucial for infants, as research suggests it can improve bone mineral content and bone mineral density, as well as prevent fractures in infants whose mother’s supplemented with vitamin D. In the UK, the government recommends that infants who are breastfed should receive a vitamin D supplement (in the form of drops) from birth. In addition to this, the UK government also recommends that Vitamins A and C are also supplemented by breastfed infants daily from aged 6 months, until 5 years of age.

Omega 3 and Omega 6

esearch is clear that essential fatty acids, namely omega-3 and omega-6 polyunsaturated fatty acids (PUFAS) are vital for the foetal brain. Growth of nerve tissue is reliant on ample amounts of these fatty acids. Research has also suggested that it is the ratios between omega-3 and omega-6 that have a heavier influence on the developing brain. In evolutionary terms, omega-6 to omega-3 ratios in earlier humans would have been approximately 1-1 due to their diet of mainly foraged plant foods. However, these ratios are skewed in favour of omega-6 fatty acids in modern times, as much as 20:1 or higher. This inconsistent rise in omega-6 levels has been shown in an animal study to affect the unborn foetus by directly competing with the uptake of omega-3 fatty acids, which are essential for normal and healthy brain development. Research has demonstrated that infants whose mothers supplemented or consume the DHA (a type of omega 3) rich foods during pregnancy may present improved cognitive processing scores. Low levels of omega-3 may increase risk of preterm birth and are associated with worse short-term outcomes in those born preterm. Certain research that investigated the fat content of baby formulas presents worrying results, as it is estimated that in the last 50-60 years linoleic acid content (omega-6 fatty acid) has increased 3-fold in baby formula. This may contribute towards the active competition between dietary fats in the foetal brain, increasing the risk of preterm birth and neurodevelopment impairment. 

Oily fish, such as salmon, mackerel and herring, and flaxseeds and walnuts, are good dietary sources of omega 3. However, it is important to note that vegetarian sources of omega 3 have to be converted by the body, and this conversion process is not always very efficient. Therefore, individuals who are following a plant based diet may benefit from supplementing with a vegan omega 3 supplement.

Iron

Iron deficiency is one of the world’s leading nutritional deficiencies. Iron deficiency is most likely to occur during pregnancy or early childhood, therefore, consuming enough of this vital micronutrient is key for the development of a foetal or infant brain. One study found that school-aged children whose mothers supplemented with iron early in pregnancy showed significantly improved intellectual and cognitive scores, compared to the control. Furthermore, research from China suggests that infants who were deficient in iron in the womb display worse auditory recognition memory. One reasons for these findings may be due to poor hippocampal development between 28 weeks gestation and first postpartum year, as a result of iron deficiency anaemia. Good sources of iron include beans, nuts, dried fruit and red meat.

Folic acid

Folic acid is essential for the growing foetus, as it is involved with DNA and RNA formation as well neurotransmitter formation. Extensive research has been done on the implications folic acid deficiency has on foetal development. Moreover, One study found that school-aged children ,whose mothers had supplemented with folic acid early in pregnancy, showed significantly improved intellectual and cognitive scores, compared to the control group.. Research has demonstrated that folic acid must be taken in correct amounts to prevent neural tube defects. The NHS recommends 400 micrograms per day for women trying to become pregnant (at least 3 months before trying for a baby). However, individuals with the following risk factors may be at higher risk of neural tube defects and may be recommended by their doctor 5mg of folic acid:

family or personal history of neural tube defects
being overweight
having diabetes
having sickle cell disease
taking epilepsy and antiretroviral medicines for HIV

B12

Vitamin B12 is another vitamin widely discussed pertaining to brain health. This micronutrient is needed for brain development, and research has been shown that maternal B12 deficiencies may cause severe health outcomes in infants, for example, reduced cognitive development and poorer intellectual abilities along with fatigue. Unfortunately, mental impairment due to B12 deficiency seems to be irreversible, thus, it is absolutely crucial that this nutrient is consumed by pregnant women throughout their pregnancy. Good sources of B12 include meat, fish, eggs and dairy products. Individuals who follow a plant based diet may benefit from supplementing B12, as this nutrient is mainly found in animal products.

Iodine

Iodine is a mineral involved heavily with cognitive development, especially during the first trimester. Deficiency of iodine is the leading cause of preventable mental impairment across the globe, and children born from iodine deficient mothers often have cretinism, symptoms include speech and communication deficits, poor gait and low IQ. It is vital that iodine is consumed in adequate amounts early on in the pregnancy as supplementation late into pregnancy does not seem to make the same improvements in cognitive development. Good sources of iodine include eggs, seaweed, shellfish, dairy products and chicken. Individuals who follow a plant based diet may benefit from supplementing iodine, as this nutrient is mainly found in animal products.

Copper, Choline & Zinc

Other micronutrients such as copper, choline and zinc are important to consider as these have been shown to play a role in cognitive development within the womb and in infants (Georgieff et al., 2019). Overall, close attention must be made by those pregnant to consume enough of these macro and micronutrients to prevent the onset of irreversible damage to the foetus. Eggs, meat, poultry, fish, dairy products, nuts, seeds and cruciferous vegetables are all sources of choline, and seafood, such as oysters, wholegrains, milk and red meat are a wonderful source of Zinc. Shellfish, seeds and nuts, organ meats, and whole-grains are all sources of dietary copper.

Final Thoughts

Further supplements may be required for infants following a vegan and vegetarian lifestyle, compared to those following omnivorous diets. However, newborns and infants who are consuming 500ml of infant formula (around 1 pint) should not be given supplements as the milk is fortified already with these nutrients.

Disclaimer: Always consult your doctor and midwife / health visitor before starting an infant on any supplements.

Nutrition and Lifestyle Information for Infancy (0-3)