More than 1 in 4 children under the age of 5 globally live in "severe" food poverty, UNICEF has warned — meaning that more than 180 million are at risk of experiencing adverse impacts on their growth and development.

"Severe child food poverty describes children who are surviving on severely deprived diets so they're only consuming two or less food groups," said Harriet Torlesse, a lead writer of a new UNICEF report published late Wednesday. "It is shocking in this day and age where we know what needs to be done."

UNICEF recommends that young children eat foods daily from five of eight main groups — breast milk; grains, roots, tubers and plantains; pulses, nuts and seeds; dairy; meat, poultry and fish; eggs; vitamin A-rich fruits and vegetables; and other fruits and vegetables.