Micronutrient Deficit

Prof. Simon J. ATEGBO

Department of Pediatrics, Libreville Faculty of Medicine and Health Sciences

Moderate or severe under nutrition remains a public health problem in developing countries [1]. The responsibility of inadequate protein, carbohydrate and lipid intake has been clearly established. Under nutrition is most often a multi deficit based; in fact, the deficit also concerns micronutrients [2]. This category of nutrients includes certain minerals, trace elements and vitamins such as iodine, iron, zinc, selenium and vitamins A, D, E, K. These deficiencies have an impact on growth, morbidity and mortality and thus constitute a public health problem. In the first months of life, these deficits are caused by the mother's unbalanced diet and inadequate dietary modalities, thus emphasizing the importance of diet during the first 1000 days of life. In developing countries, several factors contribute to the micronutrient deficiencies: inadequate food supplements, low in iron and zinc, or containing foods rich in Pythic acid, a potent inhibitor of zinc, iron and calcium absorption. This deficiency in micronutrients is also responsible for the frequency of infectious pathologies such as measles in case of vitamin A deficiency [3].

Micronutrient deficiencies have an impact on behavior and development. This was raised by mental development test scores decreased by 6-15 points in infants with iron deficiency anemia [4], or growth disorders in the event of zinc deficiency [5].

Vitamin A deficiency affects the epithelial structures of many organs, especially the eye. Immune deficiencies in vitamin A, zinc and iron have important consequences. Vitamin A plays a role in hematopoiesis, maintenance of mucosal integrity, in the function of T and B lymphocytes, natural killer cells and neutrophils, and in the generation of antibody responses to T cells and class II antigens. Zinc plays a role in the function of T and B lymphocytes, polynuclear and naturally occurring killer cells and is also involved in the generation of the antibody response to the T cells dependent and non-dependent antigens. Iron deficiency alters the defenses of the host such as cellular immunity and the function of polynuclear cells affecting bactericidal activity [6, 7]

The relationship between the relatively high incidence of micronutrient deficiencies and infectious diseases reflects both increased predisposition to infections in deficient populations and a direct effect of the infection itself on micronutrient status indicators, for example Ocular complications of measles and Vitamin A deficiency [3,8].

The consequences of micronutrient deficiencies can have a direct impact on children's cognition and learning, health spending because of the morbidity they generate.

To ensure optimal growth, health and development of the child, a comprehensive and integrated approach is needed. This approach will focus on nutrition before and during pregnancy, promotion of exclusive breastfeeding for 6 months, use of fortified food supplements, home enriching of traditional foods supplements (example of Sprinkles), promotion of available and accessible micronutrient-rich foods that are socially accepted by the population, and effective nutrition and health education campaigns [9-11]. Implementation of such an approach requires the involvement of the public health sector and the private sector.

References
1- Carlson B, Wardlaw TM. A global assessment of child malnutrition. Staff working papers No.

7 New York, UNICEF, 1990.

2- WHO. Management of severe malnutrition. Geneva 2000 D'Souza RM, D'Souza R. Vitamin A for the treatment of children with measles_ A systematic review. J Trop Pediatr 2002; 48: 323-7.

4- Pollitt E, Leibel RL. Iron deficiency and behavior. J. Pediatr 1976, 88: 372-81.

5- Agget Pj, Harries JT. Current status of zinc in health and disease states. Arch Dis Child 1979, 54: 909-17.

6- Joynson DHM, Jacobs A, Murray-walkerD, Dolty AE. Defect on cell-mediates immunity in atients with iron-deficiency aneamia. Lancet 1972, 2: 1058-9.

7- Walter T. Effect of iron therapy on phagocytosis and bactericidal activity in neutropils of iron eficient infants. Am J Clin Nutr 1986; 44: 877-82.

8- Lind T, Lönnerdal, Stenlun H et al, A community-based randomized controlled trial of iron and zinc supplementation in Indonesian infants: Interactions between iron and zinc. Am J Clin Nutr 2003;77:883-90

9- Haschke F, Ziegler EE, Edwards BB, et al. Effect of iron fortification of infant formula on trace mineral absorption. J Pediatr Gastroenterol Nutr 1986;5:768-73.

10- Dewey KG, Brown KH: Update on technical issues concerning complementary feeding of young children in developing countries and implications for intervention programs. Food Nutr Bull 2003;24:5-28.

11- SSSSSDavidsson L. Approches to improve iron bioavailability from complementary food. J Nutr 2003;133:1560S-62S.