Parents have to persevere if they want fussy eaters to expand their palette.
Child nutritionist Dr Carrie Ruxton noted the average kid needs to be offered a food type six to eight times before they will eat it.
"Young children have something called neophobia, where they're naturally reticent to try new things, whether [it is] food or anything else," she added.
Dr Ruxton went on to note it is vital that mums and dads continue to encourage their little ones to sample healthy produce in an effort to vary their diet.
The expert stated it is also a good idea to eat the food with one to five-year-olds, as this will sustain their interest in it.
Research by growingupmilkinfo.com uncovered that almost 80 per cent of parents are not aware of the specific nutritional needs of toddlers when it comes to vitamin D.
The average British toddler is only receiving 27 per cent of their recommended daily intake of the substance.
Furthermore, 75 per cent of parents mistakenly think their kids are having their nutritional needs met.