Most people never think about the iron content of food or their daily intake of this important element. With so much food around, and more than two-thirds of the population overfed, iron is a substance that is probably taken for granted by most people.
Busy counting calories, checking labels for fat, salt and sugar levels, or just trying to feed families on low incomes, iron content is the last thing on a food shopper's mind. However, the Irish Blood Transfusion Service (IBTS) recently reminded us of iron intake and anaemia, when it temporarily stopped accepting blood donations from women.
A new device, used to check haemoglobin, was giving inaccurate results in some individuals. Twenty women had donated blood before their anaemia was detected. Now the IBTS has introduced full blood counts on all donors until they are able to replace the faulty device. About 7 per cent of women who want to donate blood are anaemic and fail the full blood count test but, more worryingly, nearly one in five women who passes the test hasn’t got enough stored iron.
The amount of iron needed depends on age and sex, but the guidelines are very confusing. The latest advice from the European Food Safety Authority (EFSA) is different to the Irish healthy eating guidelines. Boys aged 14-18 need 7mgm of iron and girls of the same age need 10mgm a day, according to the Irish advice. The EFSA guideline is 11mgm and 13mgm respectively.
Women of childbearing age need 10mgm a day according to the Irish advice; Europe specifies 16mgm. Contrary to the popular belief that all pregnant women need iron tablets, the panel of experts who drew up the EFSA guidelines concluded: “No additional iron is required in pregnancy.”
Women with a normal diet will now be spared iron-tablet-induced constipation while pregnant.
The Irish and European opinions are substantially different, so which advice is the best? The Irish guidelines are from 2011 and the EFSA ones were signed off in October 2015, so they are more up to date.
The numbers of women with anaemia or with low stores of iron turning up to blood-donor clinics do not give an accurate picture of the iron health of Irish adults. In fact, the situation is much worse. Various surveys carried out by the Irish Universities Nutrition Alliance (IUNA) show many adults and children are not eating enough iron.
The National Children's Food Survey 2005 found more than a third of girls aged 5-12 and 13 per cent of boys in the same age category don't consume enough iron. A 2008 survey of teenagers found almost three-quarters of girls surveyed and nearly a fifth of boys do not have enough iron in their diet. The 2011 National Adult Nutrition Survey found adult men eat enough iron whereas women aged 18-64 do not.
Preschoolchildren have adequate iron in their diet with average intakes of 7.4mgm, just above the EFSA guideline of 7mgm.
Although these surveys are a few years old, the iron health of adults and children is unlikely to be any better now, and is probably worse. The percentages of adults and children who are overweight and obese have increased since 2005, and obesity interferes with iron absorption and storage. It seems odd that a condition caused by calorie and nutrient excess is associated with iron deficiency, but it is unfortunately true.
In fact, iron deficiency and obesity are molecularly linked and mutually affect each other, so iron deficiency is likely to be more prevalent than a few years ago. A vicious circle develops when the fatigue that accompanies iron deficiency increases inactivity, leading to even more weight gain.
The differences in iron content in the diets of men and women, and boys and girls, suggest these are related to how males and females are catered for when it comes to food.
Traditionally men and boys are given bigger portions in the mistaken belief they have bigger appetites and need to build up their strength. Being male or female is not relevant. Small people need less food and bigger people need more.
Parents must ensure portion sizes for girls are as large as for boys, particularly of meat and green vegetables, which are good sources of iron. It is also time for women of childbearing age to start looking after themselves.
Information on anaemia can be found at hse.ie.
The new European guidelines on iron can be downloaded from www.efsa.europa.eu/efsajournal.
Dr Jacky Jones is a former HSE regional manager of health promotion and a member of the Healthy Ireland Council.