2. HOW MICRONUTRIENTS AFFECT HUMAN HEALTH
2. How Micronutrients Affect
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Since the early 20th century, scientific and technical discoveries have led to improved health and prosperity for those who have been able to benefit from them. One is the discovery that food contains important vitamins and minerals, and that a deficiency in some of these can cause a range of health and developmental problem.
Five micronutrients stand apart, both because of their importance and the numbers of people who are deficient in them. These micronutrients have become the focus of highly successful programmes that have reached millions of children and adults.
VITAMIN A: Vital for survival and sight
Thanks to its powerful ability to boost the immune system, vitamin A is a critical micronutrient for the survival and physical health of children exposed to disease. Research has shown that, where a population is at risk of vitamin A deficiency, supplementation reduces mortality in children between six months and five years of age by an average of 23%. Vitamin A also helps prevent blindness in childhood.
IODINE: Fundamental for the intelligence of the next generation
Iodine is one of the most important elements required by a developing fetus because of its effect on brain development. When the intake of iodine is increased through the consumption of iodized salt, the results are impressive. In communities where iodine intake is sufficient, IQ is shown to be on average 13 points higher than in iodine-deficient communities.
IRON: Essential for maternal and fetal health, learning, and productivity
Iron is an essential mineral for human development and function. It helps produce haemoglobin, the oxygen-carrying component of red blood cells. As these cells carry oxygen to the muscles and brain, iron is critical for motor and cognitive development in childhood, and for physical activity in all humans. If iron levels are too low, the body makes too few red blood cells, and individuals develop anaemia.
Iron is also critical to the health of a pregnant mother and her unborn child. Iron supplementation during pregnancy lowers the risk of maternal mortality due to haemorrhage, the cause of more than 130,000 maternal deaths each year. Supplementation also helps to lower the risks of premature birth and low birth weight.
ZINC: Fights diarrhoea and infections and promotes growth
Zinc promotes immunity, resistance to infection, and the growth and development of the nervous system. Diarrhoeal disease causes 18% of deaths in children under five years of age. Studies have shown that zinc supplementation, given with oral rehydration therapy, can reduce the incidence of diarrhoea in children by 27%. It can also reduce the incidence of acute lower respiratory tract infections by 15%.
FOLATE: Essential for healthy fetal development
In the earliest days of fetal development, folate is one of the most important micronutrients for the emerging human being. Necessary for the production of new cells, folate promotes the healthy early development of the spine, spinal cord, skull and brain. Debilitating and sometimes deadly neural tube defects - including spina bifida - occur three to four weeks after conception if part of the neural tube does not close as it is developing. Ensuring sufficient levels of folate in women prior to conception has been shown to reduce by 50% the number of cases of neural tube defects.