Undernutrition in Children in 'Developed' Countries

Introduction

Obesity (ie, overnutrition) claims considerable attention in ‘developed’ countries and societies. Yet, deficiencies of various nutrients still occur in all societies and some are becoming more frequent. The common deficiencies seen in infants and  toddlers are described below. The table lists high risk groups for a nutrient deficiency that require special attention. This paper refers to otherwise well children, not to low birthweight babies, nor to those with a medical illness.

Breast fed infants
Breast milk contains only small amounts of vitamin K, vitamin D and iron.

Vitamin K should be given to all breast fed babies to prevent classical early haemorrhagic disease and the later rare, but often fatal, intracranial bleeding. The treatment choices are 1mg intramuscular once only, shortly after birth, or 2mg orally on 3 occasions. Normal infants receiving an infant formula from birth (either exclusively or with breast milk) do not require these extra doses of vitamin K. (1)

Vitamin D deficiency is unlikely if the mother had adequate vitamin D intakes during pregnancy, either from sun or supplements, and the baby was exposed to sunlight. However, it is difficult to be sure of all these factors and a safer policy is to give vitamin D supplements to all breast fed infants.(2) This is not the current policy in many countries, including Britain, but has recently become so in the USA .
 
Iron is not a problem initially. The new born baby does not need as many red blood cells as it does in utero. As the circulating red cells are broken down, the iron in the released haemoglobin is stored and gradually reused as the infant grows. A supply of available iron in the diet is necessary from about the age of 6 months.

Other nutrient deficiencies reported include thiamin (Asia), pyridoxine (Finland), B12 (vegan mothers) and zinc (immigrants to France).

Bottle  fed infants
If the infant takes sufficient amounts of a properly prepared infant formula there will be no deficiencies of either macro or micronutrients since infant formulas have been designed to meet the full nutritional requirements of a young infant. Their composition is closely regulated by law and the enforcement agencies.

However, ‘feeding accidents’ have occurred very occasionally because during manufacture or preparation a nutrient has been omitted or destroyed (for examples, deficiencies of pyridoxine leading to convulsions, chloride causing metabolic upset and  thiamine resulting in some deaths. (3, 4)

If a nutrient deficiency occurs in a formula fed baby, consider whether it is a symptom of some underlying disorders such as malabsorption or a ‘feeding accident.’

Toddlers
In Britain, twelve percent of all 2 year olds were anaemic. A quarter of Asian toddlers were anaemic and/or had subnormal plasma vitamin D concentrations. (5, 6)

Iron deficiency anaemia is associated with alterations of immunological, gut and mental function. Two dietary factors contribute to the problem.(7)

1. Undue reliance on whole cows milk to provide a large proportion of the total food intake may be a cause -- cows milk contains little iron and occasionally leads to intestinal blood loss
2. Limited meat consumption. Meat, because of its well absorbed haem iron is a good source; it also provides zinc.

The average toddler diet provided only 73 percent of the ’reference nutrient intake’ (RNI) in Britain. One hundred percent is desirable.
 
Vitamin D deficiency is reported with increasing frequency. Possible reasons are: (2)

1. Prolonged exclusive breast feeding – see above.
2. Increased time spent indoors and the use of sunscreens.
   Advice on prevention of skin cancer should ensure that mothers and children receive adequate solar radiation, for example, 30-60 minutes per day to face and forearms from April to September in the northern hemisphere.
3. Unusual diets such as Macrobiotic or soy health food beverages providing little vitamin D and calcium. An approved and regulated soya infant formula provides both vitamin D and calcium.
4. Migration of darker coloured races to less sunny climates.

Other nutrients
Even in developed countries, some toddlers even have unusually low plasma concentrations of vitamin A and zinc. They are not known to  cause any problems in most countries, but zinc deficiency has been associated with growth faltering in USA
 
References

1. Hey E Vitamin K-what, why and when?  Arch Dis Child (Fetal and neonatal edition) 2003; 88:80-2.
2. Wharton BA,  Bishop NJ. Rickets. Lancet 2003;362:1389-400.
3. Malloy MH, Graubard B, Moss H, McCarthy M, Gwyn S, Vietze P, Willoughby A, Rhoads GG, Berendes H. Hypochloremic metabolic alkalosis from ingestion of a chloride-deficient infant formula: outcome 9 and 10 years later.Pediatrics. 1991;87:811-22.
4. Aris B. Maker of vitamin B1-deficient baby milk admits error.  Lancet. 2003;362:1730.
5. Wharton BA  Low plasma vitamin D in Asian toddlers in Britain: If in doubt give vitamins, consider iron too, and remember other vulnerable children. BMJ 1999; 318:2-3.
6. Lawson M,Thomas M. Low Vitamin D status of  Asian two year olds living  in  England. BMJ  1999; 318:28.
7. Wharton BA. Iron deficiency in children: detection and prevention. Br J Haematol. 1999; 106:270-80.  

Table.  Risk of a  nutrient deficiency in various groups of children

A child  growing adequately (refer to growth charts) is unlikely to have protein or energy deficiency. Even in children growing adequately micronutrient deficiency may be present  in the following groups:

• Exclusive breast feeding (ie, without other foods) for more than 6 months. (iron, zinc, vitamin D and possibly pyridoxine)
• Vegetarian diet unless at least 500ml of an infant formula/follow on formula (or a soya infant formula for vegans) is consumed each day. (iron)
• Receiving cows milk before the first birthday. (iron, rarely copper, vitamin D)
• Receiving neither an infant formula/follow on formula, nor vitamin drops. (vitamin D)
• Limited exposure to sunlight between April to October (in the northern hemisphere) for examples, due to female modesty, bad weather, illness, restricted play areas, television/computer addiction. (vitamin D)
• Children of ‘immigrant’ families. (Iron, vitamin D – most countries; zinc –in France and USA)
• Unusual diets, for examples, macrobiotic, food component restriction because of perceived or real allergy, especially diets self prescribed without the help of a dietitian. 
• Children who qualify for food aid of various types, for examples, WIC in USA, Welfare Food Scheme in UK. While these schemes are designed to improve nutrition, they indicate a vulnerable group, who, if they do not register for or receive the supplements offered,  may develop under-nutrition.

This material has been prepared by B. A. Wharton on behalf of the IFM's Advisory Committee on Child Health and Nutrition, February 2006.