The ‘ideal’ kids lunch box should contain a protein-filled sandwich, a veggie snack, fruit and some dairy, according to a food expert.

Nutritionist Lucy Kerrison said it’s important to include one portion of starches, such as bread, pasta or rice, one to two portions of veggies, such as cucumber, carrot or lettuce, and one portion of fruit, such as an apple, banana or orange.

The advice follows research of 800 parents, who make packed lunches for their kids, revealed the average child’s lunchbox includes a sandwich, a pack of crisps and an apple.

The poll, commissioned by Warburtons, revealed 60% worry about ensuring their children’s pack lunches are nutritious while meeting their child’s preferences.

Sarnies were seen as the ‘safest’ option on the menu, with 20% adding them to the lunchboxes with the same filling daily – with ham most common, closely followed by cheese.

While a yoghurt was the top ‘sweet treat’ added, followed by biscuits and a chocolate bar.

The bread making company has teamed up with the nutritionist as well as Girls Aloud member and super-mum of three, Kimberley Walsh, ahead of back-to-school season.

They aim to show parents that back-to-basics lunches, such as sandwiches can be part of a healthy, balanced diet while keeping the kids happy.

When it comes to their children’s lunchbox requests – the most frequent asks were the inclusion of a particular snack or juice, sandwiches to be cut a certain way, or for their crusts to be chopped off.

Interestingly, parents spend almost 20 minutes planning and preparing their school lunchboxes each day.

In a heartwarming gesture, 64% have left notes for their little ones in their boxes – expressing love and affection, jokes or funny messages and motivational words.

Jonathan Warburton, from the bread making company, said: “Making your child’s lunchbox everyday can be a lot of pressure, as we want to ensure our children are on top form to learn throughout the day.

“The research shows how many parents are unsure about whether a sandwich is a suitable, healthy lunch option for their children, which is why we’re delighted to launch a campaign that helps make it clear they can still be a staple of the lunchbox.

“Most parents don’t have the luxury of time, convenience or money to feel like they’re feeding their kids the most nutritious meals possible.

“However, Lucy’s insights help highlight how they can pack as much nutrition as possible into the humble sandwich to provide the energy and nutrients they need.

“We’re thrilled to be working with Kimberley and Lucy to help empower parents to feel confident and secure in putting them in their children’s lunch boxes.”

Speaking on behalf of the brand, Kimberley Walsh, added: “As a busy mum of three, I understand the pressures that come with trying to make healthy, nutritious packed lunches for your kids, and it’s interesting to see from the research that other mums feel the same.

“Working on this campaign with a nutritionist has really helped me understand that going back-to-basics with a delicious sandwich is one of the best ways to ensure your child is getting all the correct nutrients they need.”

Nutritionist Lucy Kerrison said: “Whilst many parents want their kid’s lunchboxes to be as nutritious as possible and feel the pressure to do so, most don’t have the luxury of being able to do so – due to factors such as fussy kids, time poor mornings, convenience and affordability.

“That’s why sandwiches are a great lunch time option – the fibre, calcium, starch and carbohydrates are in the bread with essential fats from the butter and protein such as chicken, egg or ham in the fillings.

“With Back to School around the corner, we’re looking to educate parents about how they’re a quick and easy way to provide nutrition with recipe inspiration and top tricks to make it that little bit easier.”

It also emerged 75% were unsure whether giving their child a sandwich for lunch was a healthy option, with 79% packing one as a main in their child’s lunchbox despite only 26% believing that what they’re packing is very nutritious.

Six in 10 (61%) considered the packed lunches they make their child ‘somewhat’ nutritious, with one in 10 admitting what they pack isn’t and 39% struggle to keep things varied while 34% find it difficult to provide nutritional balance.

Of the 34% who struggle to balance their child’s lunch boxes, 48% their kids won’t eat the ‘good’ items they add in. And 42% struggle to find items that’ll keep, according to the OnePoll.com data.