Giving babies an egg every day could be the best way to help them thrive, scientists believe.
A daily egg reduced their chances of stunted growth or becoming underweight and made them less likely to eat sugary food.
They also had higher levels of important nutrients such as vitamin B12 in their blood compared with those who were not regularly consuming eggs.
The often messy ritual of feeding infants an egg each day has fallen out of favour.
Dr Lora Iannotti, of Washington University in the US, divided children aged six to nine months into two groups – one of 83 children who were fed an egg a day and another of 80 who had eggs less often. The study, published in the journal Pediatrics, found cases of underweight children fell by 74 percent in the group given eggs. Stunted growth fell by 47 percent and they also ate less sweetened food.
Dr Iannotti said: "Eggs can be affordable and easily accessible.
"They are a good source of nutrients for growth and development in young children. We were surprised by how effective this intervention proved to be."