Even though these little kids in New Zealand are eating enough zinc-rich food, almost 4 out of 10 of them still have low zinc levels in their blood — which means what they eat might not be turning...

Even when toddlers eat enough zinc-rich foods, their blood tests might still show low zinc — which means the usual way doctors check for zinc deficiency might not be working right.

Giving toddlers in New Zealand more zinc through meat or special milk doesn’t seem to raise the zinc levels in their blood or hair, so just eating more zinc might not fix low zinc levels in their bodies.

Giving zinc supplements to infants at intervals is linked to fewer cases of mild respiratory infections and fewer severe cases of diarrhoea, with a stronger effect on the more serious diarrhoea cases.

Giving babies in Bangladesh a daily zinc pill for 6 months raises the zinc in their blood, but it doesn't change their immune system's gene activity or signaling molecules — so if zinc helps them, it's probably working in ways we can't see with standard blood tests.

Giving infants zinc supplements at intervals may lead to slightly greater increases in height and weight over six months compared to normal growth patterns seen in low-resource areas.