What children primarily require is sufficient food energy i.e. calories rather than protein per se. With adequate calories an individual will be in positive nitrogen balance and will thrive on a diet in which protein is available from a mix of plant-based foods.
After birth, if a woman's breast milk contains too little B12, deficiency can then occur in her infant - not in the first few weeks of life but after a few months when his or her own stores have run down. B12 problems in breastfeeding infants of vegan mothers remain very rare. Requirements include 0.3 micrograms per day for infants aged 0-6 months and 0.4 microgramsfor infants aged 6-12 months. Children from 1-10 years of age should consume 1 microgram increasing to 2 micrograms per day. B12 deficiency in infancy and childhood is rare. However, because deficiency can have severe effects, and because natural plant sources of the vitamin are in serious doubt, it is important for vegan families to use and give their children fortified foods or supplements.
Except in northern latitudes, most people obtain vitamin D from exposure to sunshine, rather than food. Consequently the UK has a set Reference Nutrient Intake (RNI) only for people most at risk from deficiency - that is infants from 8.5 micrograms dropping to 7 micrograms per day. Formula feeds contain sufficient vitamin D for infants but breast milk may not supply adequate amounts after 4-6 months of age especially in northern countries in the winter. Even in the general population, some autumn-born babies who are solely breast fed throughout winter may develop a deficiency, because the vitamin D content of their mother's breast milk is low. Nutritional rickets is more likely to occur under these conditions in dark-skinned people, especially if traditional clothing limits exposure to sunshine. Brief daily exposure of the skin to daylight in spring, summer and autumn, although not at the hottest times of the day, nor necessarily in direct sunshine, will ensure adequate vitamin D. Alternatively vitamin D fortified foods or supplements are an option for solely breast-fed infants and at weaning.
Calcium deficiency has not been reported in vegan children. Given the importance of calcium intake during youth on the future risk of osteoporosis, vegan parents like any others should ensure calcium-rich foods in the diet. The RNIs are: 350-550mg per day for infants and children to the age of 10 years, 800mg per day for teenage girls, 1000mg per day for teenage boys.
Infants can absorb up to 50% of the iron in human breast milk but it is calculated that only 10% of the iron in formula milks is absorbed. A 1981 survey of British vegan children aged 1-4.6 years found an average iron intake of l0mg per day, mainly from wheat and pulses, which considerably exceeds the British RM of 6.1-6.9mg per day. A follow up study at the ages of 5.8-12.8 years confirmed that all the children were still consuming the RNI for iron. The 1991 UK RNI is: 0-3 months - 1.7mg per day; 4-6 months - 4.3mg per day; 7-12 months - 7.8mg per day; children up to 10 years - 6.1-8.7mg per day (depending on age); and teenagers from 11.3-14.8mg per day.
There is evidence from the general population that malformations occurring in some infants may be linked to zinc insufficiency in their mothers. Human milk is not a rich source of this mineral and during breastfeeding infants draw on their body reserves laid down during the last 3 months of pregnancy. Thus premature babies may be at risk of zinc deficiency. UK recommendations are 0-6 months - 4mg/day; 7 months-3 years - 5mg/day; 4-6 years - 6mg/day; 7-10 years - 7 mg/day.