Optimum nutrition is fundamental for the development of a child’s full potential and there are studies that link chronic undernutrition and micronutrient deficiency to cognitive deficits.
Undernutrition has been shown to negatively impact various developmental and cognitive areas including motor development, language functioning, intelligent quotient (IQ), as well as memory and executive functions. The brain needs nutrients to build and maintain its structure.
Poor nutritional status during childhood may have long-term negative consequences and restrict the development of a child’s full potential, especially in behaviour, development and reduced cognitive ability. Numerous studies have shown the impact of nutrition and cognitive development. Here we briefly discuss the impact of the minerals iron and selenium to shed light in this area.
One study investigated the association between cognitive performance, iron biomarkers and serum selenium in 541 children (aged 4.5-5 years) from rural Ethiopia. This study found that anaemia and selenium deficiency were associated with poor cognitive performance. Children with coexisting anaemia, iron and selenium deficiency, and stunting had lower cognitive scores. Children with two or more co-existing nutrient deficiencies scored significantly lower than children affected by a single nutrient deficiency in all of the cognitive tests.
Iron deficiency is one of the world’s common single nutrient deficiencies with approximately 25% of the world’s populations being affected by anaemia. Iron deficiency anaemia in early life is related to altered behavioural and neural development.
Iron plays an important role for the synthesis of neurotransmitters and myelination,[1,3,6] and is essential for oxygenation, modulation of cerebral development and to produce energy in the cerebral parenchyma (functional tissue in the brain). Deficiency of iron has been associated with poorer cognitive performance, alterations in brain energy metabolism, apathy, irritability, decreased attention and inability to concentrate.
Anaemia is also a significant risk factor for cognitive deficit. Children with anaemia in the study above had lower score for the verbal reasoning test. Severe iron deficiency during early childhood induces cognitive deficits that can persist after 10 years of treatment with iron.
Selenium is a potent antioxidant and is involved in neurodegeneration, thyroid function and immune response, along with having anti-inflammatory properties. Selenium is known to influence the process of synaptogenesis, myelination and neuronal cell differentiation by regulating thyroid hormones.
The brain is one of the organs with high concentration of selenium. Selenium may impact cognitive function by protecting the brain from oxidative damage and deficiency alters neurological development. Selenium deficient children have lower scores on all cognitive tests than normal children (p < 0.05).
Minerals, particularly iron and selenium, play major roles in cognitive development and maintenance. Further research is suggested to investigate the effects of nutrition, particularly minerals, for cognitive development and maintenance in children.
- Gashu D, Stoecker BJ, Bougma K, et al. Stunting, selenium deficiency and anemia are associated with poor cognitive performance in preschool children from rural Ethiopia. Nutr J 2016;15:38. [Full Text]
- Kitsao-Wekulo P, Holding P, Taylor HG, et al. Nutrition as an important mediator of the impact of background variables on outcome in middle childhood. Front Hum Neurosci 2013;7:713. [Full Text]
- Bourre JM. Effects of nutrients (in food) on the structure and function of the nervous system: update on dietary requirements for brain. Part 1: micronutrients. J Nutr Health Aging 2006;10(5):377-385. [Abstract]
- Wachs TD. Relation of mild-to-moderate malnutrition to human development: correlational studies. J Nutr 1995;125(8 Suppl):2245S-2254S. [Abstract]
- Liu J, Raine A. Nutritional status and social behavior in preschool children: the mediating effects of neurocognitive functioning. Matern Child Nutr 2017;13(2). [Full Text]
- Beard J. Iron deficiency alters brain development and functioning. J Nutr 2003;133(5 Suppl 1):1468S-1472S. [Abstract]
- Zoidis E, Seremelis I, Kontopoulos N, et al. Selenium-dependent antioxidant enzymes: actions and properties of selenoproteins. Antioxidants (Basel) 2018;7(5). [Full Text]