Human Nutrition Review – Roisin Mc Donagh HNUT5 18428822 Introduction Iron ‘s RDA differs depe nding on age and gender

Human Nutrition Review – Roisin Mc Donagh HNUT5 18428822
Iron ‘s RDA differs depe nding on age and gender. For adolescents the RDA is 1 4mg/day . (FSAI 1999)
There are two type s of iron haem and non -haem. Haem iron is mainly from animals i.e. meat, poultr y,
fish. Non -haem is from plant s i.e. legumes, green leafy vegetables and fortified cereals. Iron is a
component of haem oglobin which is a pigment in red blood cells that helps to transport ox ygen
around the body. It is a component of myoglobin . This is how oxygen is stored in muscles. It is a
cofactor f or many enzymes in DNA synthesis, energy metabolism and antioxidants. It is vital for
cytochromes whic h are involved in the TCA cycle.

Iron deficiency anaemia is defined as a haemogl obin level below the cut off value for age and gender
and at least two other irregular iron status measurements i.e. serum ferritin, transferrin saturation,
RBC protoporphyrin and haemoglobin levels. (Gibney et al. 2010) Symptoms include fatigue, paleness,
shortness of breath an d cold hands and feet. This result s from less haemog lobin in the blood which
means less oxygen is being transported, making symptoms more prominent. Ob servational research
shows adolescents are not mee ting iron requirements. However, boys are closer to reaching
requirements than girls. (Vandevijvere et al. 2013) Adolescents have high iron requirements as t hey
are growing rapidly, and girls need increased amounts for menstruati on. (Wharton et al. 1987) This
loss of blood and quick growth puts adolescents at risk of anaemia. The study observed the sources of
iron. Haem iron sources are more bioavailable than non -haem sourc es. It contained a random group
of over 3000 adolescents fr om Europe aged 12 -18 conducted over 2 weeks. Dietary intake was noted
us ing a 24 -hour recall on two non -consecutive days. S elf -recorded questionnaire s were taken about
(A, 2005 -2006) participants socio -eco nomic backgrounds. The adolescents weight and height were
recorded . It found that the total iron intake for boys was higher th an for girl s. Boys consumed
13.8mg/day and girls 11mg/day. 97.3% of boys met the requirements compared to 87.8% of girls.
From thi s study we see girls are at a higher risk of developing anaemia than boys as less meet
requirements. (Vandevijvere et al. 2013)
81% of Irish teenagers consume ‘ready to eat ‘ breakfast cereals. (Flynn et al. 2005 -2006) Experimental
research shows that the fortification of breakfast cereals has a positive impact on iron status. (Powers
et al. 2016) In this trial 71 girls aged 16 -19 who did not consume breakfast cereals more than four
times a week were studied in a random, double blind, place bo -controlled intervention over a 12 -week

period. 55% of their iron intakes was lower than RNI s or DRIs. The study found daily intake s of iron
increas ed from a mean of 8.9mg/day pre -inventi on to a mean of 13.1mg/day post -intervention when
fortified cer eals were consumed. This is a sig nificant increase. S ome girls were still below the sets of
requirements, but none fell below the LRNIs for the UK. N o haemoglobin increas e was noticed. T here
was no difference in haemoglobin concentrations between the two groups afterwards. Transport of
iron to the site of haemoglobin synthesis was never compromised. (Powers et al. 2016)
Iron is a mineral of major importance to teenagers as it is a component of haemoglobin and it supports
mu scle dev elopment during growth spurts . Research shows that changes, like increasing haem iron in
the diet and the fortification of foods can improve iron intake among adolescence.

Flynn, A et al. (2005 -2006) ‘National Teens ‘ Food Survey ‘ Irish Universities Nutrition Alliance . Available
at (Accessed on 29th November 2018)
Food Safety Authority Ireland (1999). Recommended Dietary Allow ances for Ireland. Food Safety
Authority Ireland. Available at (Accessed on 18 November
Gibney, MJ. et al. (2010) Introduction to Human Nutrition Second E dition. Wiley -Blackwell.
Powers HJ. Et al. (2016) ‘Fortified breakfast cereals consumed daily for 12 wk leads to a significant
improvement in micronutrient intake and micronutrient status in adolescent girls: a randomised
controlled trial’, Nutr ition Journ al, 15, pp 69. Available at : -016 -0185 –
6. (Accessed on 7 November 2018)
Vandevijvere, S. et al. (2013) ‘Intake and dietary sources of haem and non -haem iron among Europ ean
adolescents and their association with iron status and different lifestyle and socio -economic factors’,
European Journal of Clinical Nutrition, 67, pp 765 -772 . Available at: ejcn.2013.100 (Accessed on 7 November 2018)
Wharton, B. et al. (1987) ‘Nutrition in Adolescen ce’, Nutrition and Health , 4(4), pp. 195 –203. (Accessed on 29 November 2018)