Normal nutritional requirements across childhood: Viva

Branch 1: Assessing whether requirements are met

The candidate should recognise that this child is meeting her energy requirement, shown by her weight on the 50th centile, but failing on at least one micronutrient, shown by her iron deficiency anaemia. The key teaching point is that a normal weight does not exclude micronutrient deficiency, and excessive milk intake is a classic cause of iron deficiency in toddlers. [10]

A strong candidate would explain that nutritional assessment combines a diet history, a focused examination and anthropometry, and that the growth chart is the most sensitive test of whether requirements are met. Her weight tracking on the 50th centile shows energy adequacy, but her pallor and anaemia reveal the iron gap. The clinician should never conclude that nutrition is adequate from weight alone. [7]

If the examiner presses on the assessment method, the candidate should describe plotting weight, length and head circumference on WHO growth standards, taking a structured diet history including milk type and volume, and examining for signs of micronutrient deficiency and chronic disease. The diet history here would immediately reveal that 800 millilitres of cow's milk per day is well above the recommended maximum of about 500 millilitres. [10]

Branch 2: The requirement across childhood

If asked about the requirement at her age, the candidate should state that a two-year-old needs about 80 kilocalories per kilogram per day and about 1.05 grams per kilogram per day of protein. The candidate should then show command of the trajectory: the per-kilogram requirement is highest in infancy at about 80 to 120 kilocalories per kilogram per day and falls to about 40 to 55 kilocalories per kilogram per day by late adolescence, while the absolute daily intake rises throughout childhood. [1]

A strong candidate should explain why this pattern exists. Total energy partitions into basal metabolism, physical activity, the thermic effect of food, losses, and the energy deposited as new tissue. Growth is the component that makes the paediatric requirement higher than the adult one per kilogram, and its cost falls as growth velocity slows, which is why the per-kilogram requirement declines with age. [1]

The candidate should be able to quote the key micronutrient rules: vitamin D at 400 international units per day for all ages, iron at 1 milligram per kilogram per day for breastfed term infants from four months, and cow's milk delayed to twelve months as a main drink. The examiner may probe why cow's milk is capped in toddlers, and the answer is that excess milk causes occult gastrointestinal blood loss and displaces iron-rich foods. [6]

Branch 3: Correcting the deficit

If asked about management, the candidate should reduce her cow's milk intake to about 500 millilitres per day, introduce iron-rich foods, and treat the anaemia with oral elemental iron at about 3 to 6 milligrams per kilogram per day until the haemoglobin normalises and for a further two to three months to replete stores. The milk reduction is the key to preventing recurrence. [7]

A strong candidate should explain that a therapeutic trial of oral iron with a measured rise in haemoglobin over four weeks confirms dietary iron deficiency without invasive testing, provided the cow's milk intake is addressed at the same time. Treating the iron without addressing the milk will fail. [7]

If the examiner extends the scenario forward, the candidate should describe how her requirement will change through school age and adolescence, noting the final surge of growth that raises iron needs in menstruating females and calcium needs for peak bone mass accrual. This shows that the candidate understands requirements as a trajectory, not a single number. [1]