Iron Methodology
The sampling methodology that was used in this study was arrived at to provide at least 500 boys and girls in different age and gender groups covered by Nutrient Reference Values to enable a substantive number to take part in statistical comparisons of dietary intakes with recommendations. A sample of 400 participants predominantly Australian children contributed towards this booster sample. Face-to-face interviews were conducted in the participants’ homes. Telephone interviews were also conducted utmost 2 weeks after the face-to-face interviews. Face to face interviews and telephone interviews were conducted on different day types and at appropriate times. Nevertheless, information was collected on school and non-school days in proportion to the number of such days that occurred over the sampling period. Food supplements were collected from participants by use of standardized, computer-based, three-pass 24-hour recall methodology during the face to face and telephone interview. Standard measuring cups and spoons and Food Model booklet were used in estimating foods and beverages that were consumed by the participants.
Dieticians constantly checked all the 24-hour recalls to ascertain the consumption pattern. Unusual intakes were interrogated and modification done if need be. A food coding system was developed to bring into scope the current food supply. Data obtained from food, beverage, and supplement intake were translated to daily nutrient intake data by the use of recent nutrient composition database. Iron intake in children aged between 14-18 years was 16.3 in boys and 11.1 in girls in same age group. The total amount of iron that was supposed to be taken by children aged between 14-18 years was supposed to be 13.8 mg/day. The proportion of boys aged between 14-16 years who met the estimated average requirement for iron was 99 compared 89 of the girls in the same age group. All children between the ages of 14-16 years had a proportion of 99. The percentage of children aged between 14-16 who consumed supplements were 3.8 for boys and 8.6 for girls. This shows that girls who have reached puberty require much iron supplements than boys.
Dietary Iron Requirements across Different Ages
Recommended Dietary Allowances for Iron in children and adolescents aged between 5-18 years should be as shown in the table below.
Recommended Dietary Allowances for Iron for Children and Adolescents.
Source: Institute of Medicine. Food and Nutrition Board. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium and Zinc. Washington, DC: National Academy Press, 2001.
From the table, it is observed that the three intake values: RDI, EAR, and UL are all different. This can be explained from the definition of these three Iron Nutrient Reference Values. EAR (Estimated Average Requirements) is the level of nutrient that an average person requires to support normal life activities, RDA (Recommended Dietary Allowances) is the amount of nutrient required to keep a person healthy, while UL (Tolerable upper intake levels) is the maximum amount of nutrient that a person may consume without suffering from any side-effects. As expected, EAR values for Iron are the least because this is the least amount required to maintain basic life processes without suffering from deficiency symptoms, RDI values follow in magnitude because they indicate the level of Iron that should be consumed so that one can be healthy, while the UL values are largest in magnitude as they indicate the highest levels that if surpassed, may lead to toxicity and severe various health implications.
Generally, Iron requirement among boys is lower or equal to that required by firls in the age group studied. The RDA for children aged between 14-18 years is 11 in males compared to females’ 15. This could be because this is a stage in life when girls are at puberty and start to realize menstrual cycles, a period when they loose too much blood and iron. As a result, a lot of iron is needed to cover up for those that have been lost. At pregnancy, women need more iron in anticipation for blood lost at birth as opposed to when they are lactating hence the 27mg/day iron compared to 10mg/day at lactation. Iron is also very critical during pregnancy to support the growth of the fetus and for purposes of enhancing the health of the mother. Pregnant women require double the quantity of iron compare to women who are not pregnant because during pregnancy, their blood volume increases. However, breastfeeding mothers require little iron since it can get into the infant’s circulatory system through breastmilk and reach UL values.
Iron Nutrient Values
Brigham, Beard, Krimmel, and Kenny state that intake of iron that is recommended for each stage of life should be as follows: Children following in the age of, 1-3 years should take 9mg/day, 4-8 years 10 mg/day, 9-13 years 8mg/day, those falling within the age bracket of 14-18 years (boys) 11 mg/day, and the girls in the similar age group 15 mg/day. Hurrell asserts that pregnant women are required to take a total of 27mg/day. However, because it is difficult to each that much iron in day, it is recommended that supplements are taken. The UL for iron is normally 45mg/day for adults which if exceeded can cause stomach upsets. Vegetarians are advised to take twice as much of RDA since absorption of iron from plant materials is not as efficient as in animal sources.
Health Implications of Iron Deficiency
Iron is a very important component of the circulatory system, especially in supplying blood to various body organs and tissues. In fact, the red color of blood is due to the strong bonds between Iron and Oxygen. These two elements are found naturally on earth and combine to form a red-colored compound that gives blood its distinctive red color. The compound is very vital for life.
The basic function of Iron is in the red blood cells. Once here, it combines with a protein referred to as hemoglobin. When we inhale, oxygen combines with hemoglobin to form oxyhemoglobin, which is transported to body tissues and organs by the red blood cells. Once it reaches these tissues, oxygen is released and aides in the production of energy.
Sempos, Looker, Gillum, and Makuc state that Iron deficiency anemia is one of health condition that affects children and adolescents that fall within the age bracket of 5-18 years. It begins when there is negative iron balance in the human system hence the depletion of iron that is stored in the body as held by Auer et al and Dallman. The storage sites of iron become deficient. The level of iron in the blood cannot therefore meet the daily needs of the human body as posited by Andrew. Consequently, the blood hemoglobin falls below the recommended levels state Meyers, Jensen, and Menitove. This kind of anemia comes about as a result of low dietary intake of iron. The intestinal absorption of iron may also be inadequate.
This condition can also be caused by excessive bleeding. The condition is very common in women who have reached child bearing age and expectant women. Teenage girls are the commonest victims of this medical condition because they need a lot of iron. Women who experience heavy menstrual losses are also at risk group because they loose significant amounts of iron during this process. Those individuals who fall in the age of 5-18 years and have kidney complications, more so those who are undergoing kidney dialysis can also develop iron deficiency anemia. This is principally because their kidney cannot create a hormone that is pivotal in Red Blood Cell formation posits Bhaskaram, Danesh and Appleby. This category of people need frequent supply of iron and erythropoietin to avert the danger associated with their deficiencies.
Apart from general fatigue and exhaustion, inadequate Iron in children and adolescents can cause a number of health implications. Severe lack of Iron causes anemia which may lead to shortness of breath, palpitations, impaired cognitive development, adverse pregnancy results in women and dizziness. In children, anemia may cause poor concentration leading to poor academic performance. Lack of iron can cause soreness at the corner of the mouth and tongue.
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