Growing Child 11Brain development is a long term process, with different parts and functions of the brain developing at different time points in childhood.1  Especially during the first years of life, the brain is undergoing rapid development.2 During this phase, adequate dietary intake is of special importance for the developing brain, with nutrients like iron, iodine and omega-3 and omega 6 fatty acids playing a vital role.

The importance of the first years

The brain reaches about 80% of its final weight at the age of two years,3 while the density of synapses (the meeting points between nerve cell and other cells) by the same age exceeds the adult mean.4 However, the formation of the outer layer of the nerve cell (myelination), of some parts of the brain continues also during adolescence, particularly of those nerve cells (neurons) that control higher cognitive functions.5

During the first years, toddlers acquire particular cognitive and motor skills. Their spoken vocabulary increases significantly, they gain greater motor coordination and they become able to concentrate on tasks for slightly longer periods.6  The development of these skills is the result of the interplay between genetic factors and a wide range of environmental determinants. Among those environmental determinants, visual and sound stimulation contribute importantly to the development of neural circuits.7,8  Also of great importance is the quality of dietary intake, which ensures that the brain receives all necessary nutrients for optimal development and proper function.9 Since the brain does not develop homogenously, the potential effect that a nutrient deficiency has on neurodevelopment depends on the severity, duration and timing of the deficiency.10

The role of nutrients

Understanding the role of some key nutrients involved in the brain neural development of toddlers, the European food safety authority EFSA has approved certain health claims related to those nutrients (Table 1). These nutrients and their role in neurodevelopment and growth are described below.

Table 1. EFSA approved health claims related to neural development in children   

Nutrient EFSA approved health claim Food source
Iron “Iron contributes to normal cognitive development of children” Meat, fish, poultry, iron-fortified products, such as cereal, breads, breakfast bars.
Alpha-linolenic acid (ALA) & linoleic acid (LA), essential fatty acids “Essential fatty acids are needed for normal growth and development of children” LA: Nuts, seeds, and vegetable oils such as sunflower, safflower, corn, and soybean based oils and spreads.

ALA: Flaxseed, canola, and soybean (and the relevant oils and spreads).

Fish fatty acids: docosahexaenoic acid (DHA) “ DHA intake contributes to the normal visual development of infants up to 12 months of age”

“DHA maternal intake contributes to the normal brain and eye development of the foetus and breastfed infants”


Iron plays an important role in the cognitive development of children, as it is necessary for basic neuronal processes such as myelination, neurotransmitter production and energy metabolism.11,12  Iron deficiency and iron deficiency anemia are two of the most common and widespread nutritional disorders. Specifically, the World Health Organization (WHO) has reported that iron deficiency anemia affects approximately 39% of children younger than 5 years in developing countries and 20% in industrialized countries based on blood hemoglobin concentration and that this disorder has adverse effects on cognitive development as well as on psychological and mental functions.13,14

Essential fatty acids

Alpha linolenic acid (ALA, an omega-3 fatty acid) and linoleic acid (LA, an omega-6 fatty acid) are essential fatty acids (EFAs) since they cannot be synthesized by the body. These fatty acids are needed for the normal growth and development of children16 as they play an important role in neuronal membrane structure, synaptogenesis and myelination.17  Furthermore, ALA is a precursor of docosahexaenoic acid (DHA), a longer chain omega-3 fatty acid which compromises 20% of the brain’s lipid content. The above highlights the need of adequate dietary omega-3 and omega-6 fatty acid supply in early childhood.18,19  For the age >6 months to 24 months an adequate daily intake of 100mg DHA has been set, whereas for older children there is a dietary advice regarding fish consumption (1 to 2 fatty fish meals per week).18  Nevertheless, some limited data in toddlers have reported low (below the recommended ranges) percentages of energy intake deriving from polyunsaturated fat.20,21


Iodine contributes to normal growth, since it is an essential component of the thyroid hormones.22 Thyroid hormones are necessary for the optimal brain development, while iodine deficiency disorders range from mild goiter to the very severe forms of cretinism (congenital, severe, irreversible mental and growth retardation) that arise from iodine deficiency during gestation or during the first months of life.20,23  While in several European countries insufficient iodine intake has been reported in school-aged children,23 there is limited data referring to toddlers.15


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  22. Scientific Opinion on the Substantiation of a health claim related to Iodine and the growth of children pursuant to Article 14 of Regulation (EC) No 1924/20061; EFSA Journal 2009; 7(11):1359.
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