Micronutrients, often referred to as vitamins and minerals, are vital to healthy development, disease prevention, and wellbeing. With the exception of vitamin D, micronutrients are not produced in the body and must be derived from the diet1.
Though people only need small amounts of micronutrients, consuming the recommended amount is important. Micronutrient deficiencies can have devastating consequences. At least half of children worldwide younger than 5 years of age suffer from vitamin and mineral deficiencies2. The World Health Organization recommends multiple types of interventions to address nutrition deficienciesexternal icon3.
The role of six essential micronutrients is outlined below.
- Iron is critical for motor and cognitive development. Children and pregnant women are especially vulnerable to the consequences of iron deficiency3.
- Iron deficiency is a leading cause of anemia which is defined as low hemoglobin concentration. Anemia affects 40% of children younger than 5 years of age and 30% of pregnant women globally4.
- Anemia during pregnancy increases the risk of death for the mother and low birth weight for the infant. Worldwide, maternal and neonatal deaths total between 2.5 million and 3.4 million each year5.
- Vitamin A supports healthy eyesight and immune system functions. Children with vitamin A deficiency face an increased risk of blindness and death from infections such as measles and diarrhea6.
- Globally, vitamin A deficiency affects an estimated 190 million preschool-age children6.
- Providing vitamin A supplements to children ages 6-59 months is highly effective in reducing deaths from all causes where vitamin A deficiency is a public health concern6.
- Vitamin D builds strong bones by helping the body absorb calcium7. This helps protect older adults from osteoporosis.
- Vitamin D deficiency causes bone diseases, including rickets in children and osteomalacia in adults7.
- Vitamin D helps the immune system resist bacteria and virsues7.
- Vitamin D is required for muscle and nerve functions7.
- Available data suggest that vitamin D deficiency may be widespread globally8.
- Bodies make vitamin D from sunlight, but this varies based on geography, skin color, air pollution, and other factors. Also, sunlight exposure needs to be limited to avoid risk of skin cancer.
- Iodine is required during pregnancy and infancy for the infant’s healthy growth and cognitive development9.
- Globally an estimated 1.8 billion people have insufficient iodine intake.
- Iodine content in most foods and beverages is low.
- Fortifying salt with iodine is a successful intervention – about 86% of households worldwide consume iodized salt10. The amount of iodine added to salt can be adjusted so that people maintain adequate iodine intake even if they consume less salt11.
- The American Thyroid Association and the American Academy of Pediatrics recommend that pregnant or breastfeeding women take a supplement every day containing 150 micrograms of iodine. The American Thyroid Association recommends women who are planning a pregnancy consume a daily iodine supplement starting at least 3 months in advance of pregnancy.
- Everyone needs folate (vitamin B9) to make new cells every day.
- Folate is essential in the earliest days of fetal growth for healthy development of the brain and spine12. Folic acid is another form of vitamin B9. Women of reproductive age need 400 micrograms of folic acid every day12.
- Ensuring sufficient levels of folate in women prior to conception can reduce neural tube defects such as spina bifida and anencephaly12.
- Providing folic acid supplements to women 15-49 years and fortifying foods such as wheat flour with folic acid reduces the incidence of neural tube defects and neonatal deaths13.
- Zinc promotes immune functions and helps people resist infectious diseases including diarrhea, pneumonia and malaria14,15,16. Zinc is also needed for healthy pregnancies14.
- Globally, 17.3% of the population is at risk for zinc deficiency due to dietary inadequacy; up to 30% of people are at risk in some regions of the world17.
- Providing zinc supplements reduces the incidence of premature birth, decreases childhood diarrhea and respiratory infections, lowers the number of deaths from all causes, and increases growth and weight gain among infants and young children17.
- Providing zinc supplementation to children younger than 5 years appears to be a highly cost-effective intervention in low- and middle-income countries18,19.
- Kraemer K, , Badham J, Christian P, Hyun Rah J, eds. Micronutrients; macro impact, the story of vitamins and a hungry worldexternal icon. Sight and Life Press; 2015.
- The state of the world’s children 2019; children, food and nutrition: growing well in a changing worldexternal icon. UNICEF; 2019.
- World Health Organization. e-Library of evidence for nutrition actionsexternal icon. Accessed June 18, 2021.
- World Health Organization. WHO global anaemia estimates, 2021 editionexternal icon. Accessed June 3, 2021.
- Stevens GA, Finucane MM, De-Regil LM, et al. Global, regional, and national trends in haemoglobin concentration and prevalence of total and severe anaemia in children and pregnant and non-pregnant women for 1995-2011: a systematic analysis of population-representative dataexternal icon. Lancet Glob Health. 2013;1(1).
- World Health Organization. Guideline: vitamin A supplementation in infants and children 6-59 months of age; 2011external icon. Accessed June 18, 2021.
- National Institutes of Health Office of Dietary Supplements. What is vitamin D and what does it do?external icon Accessed June 18, 2021.
- Roth DE, Abrams SA, Aloia J, et al. Global prevalence and disease burden of vitamin d deficiency: a roadmap for action in low- and middle-income countriesexternal icon. Ann N Y Acad Sci. 2018;1430(1).
- Andersson M, Karumbunathan V, Zimmermann MB. Global iodine status in 2011 and trends over the past decade.external icon J Nutr. 2012;142(4):744-750.
- Iodine Global Network. What is being done internationally about iodine deficiency?external icon Accessed June 18, 2021.
- World Health Organization. Iodization of salt for the prevention and control of iodine deficiency disordersexternal icon. Accessed June 18, 2021.
- Centers for Disease Control and Prevention, National Center on Birth Defects and Developmental Disabilities. Folic acid helps prevent some birth defects. Accessed June 18, 2021.
- Blencowe H, Cousens S, Modell B, Lawn J. Folic acid to reduce neonatal mortality from neural tube disordersexternal icon. Int J Epidemiol. 2010;39 Suppl 1(Suppl 1):i110-i121.
- Ackland ML, Michalczyk AA. Zinc and infant nutritionexternal icon. Arch Biochem Biophys. 2016;611:51-57.
- Lassi ZS, Moin A, Bhutta ZA. Zinc supplementation for the prevention of pneumonia in children aged 2 months to 59 months.external icon Cochrane Database of Systematic Reviews 2016, Issue 12. Art. No.: CD005978.
- Liu E, Pimpin L, Shulkin M, et al. Effect of zinc supplementation on growth outcomes in children under 5 years of age.external icon Nutrients. 2018;10(3):377.
- Wessells KR, Brown KH. Estimating the global prevalence of zinc deficiency: results based on zinc availability in national food supplies and the prevalence of stuntingexternal icon. PLoS One. 2012;7(11):e50568.
- Fink G, Heitner J. Evaluating the cost-effectiveness of preventive zinc supplementationexternal icon. BMC Public Health. 2014;14:852.
- Brown KH, Hess SY, Vosti SA, Baker SK. Comparison of the estimated cost-effectiveness of preventive and therapeutic zinc supplementation strategies for reducing child morbidity and mortality in sub-Saharan Africa.external icon Food Nutr Bull. 2013;34(2):199-214.