Packing school lunches can be difficult, particularly if your child is a picky eater.

But a University of Guelph nutrition professor says parents are far too often turning to less healthy snack foods to fill their children's lunchbox.

There's nothing wrong with the idea of snacking, said Jess Haines, an associate professor in family relations and applied nutrition at the University of Guelph and the associate director of the large-scale Guelph Family Health Study.

"Little kids do need to eat more frequently. They have a smaller belly and they need to eat to sustain [and] meet their energy needs," said Haines, a mother of two who admits packing lunches is one of her least favourite parenting tasks.

"It's fine if we want to graze throughout the day."

The problem comes with what children are eating.

"The main issue is that we have to be thoughtful about making sure that our health choices, both in our meals as well as our snacks, are healthful foods from our food groups as opposed to those processed foods that would fall into the 'other' category," she said.

Nova Scotia Students Child Care school lunches

When packing lunches, Haines suggests things like fruits and veggies can be made more exciting with dips or hummus. (CBC)

Girls given more sugar

As part of the study, the researchers did a small sample study looking at 50 children and their snacking habits. The children were between 18 months and five years of age.

They found snacks made up a third of the caloric intake for children and Haines said the concern is the habit of filling up on snacks could last a lifetime.

The study also found girls were more likely to be given sugary snacks than boys.

Haines said it's interesting to consider why that is the case. Is there a difference in how boys and girls are nurtured? Could it be advertising that sends different health messages to different genders?

"Ads for women often tell us that we deserve a healthy treat whereas our marketing for men would never include that type of messaging," she said.

"So this is sort of preliminary, but it is interesting and interesting to think a bit about why. We want to replicate this in a larger sample to see if this holds true when we have more children."

Back to School snacks

Avoid the prepackaged foods, Haines recommends. (Ryan Cooke/CBC )

Make it small and healthy

Haines said parents don't have to throw up their collective hands when it comes to packing a lunch that their children will actually eat.

She suggests avoiding the prepackaged items and reach for an apple, whole grain crackers and carrot sticks. If your child needs extra incentive to reach for the healthy items, give them a little extra like hummus or dip to help boost the flavour.

Also consider making smaller sandwiches so it appears more snack-sized, but is still healthy. Even a smaller portion of leftovers from dinner may be more pleasing to snacking students.

Time constraints can be a problem, with parents also dealing with making dinner, homework and taking their children to hockey practise or dance class. But a small amount of extra effort could help children develop better eating habits later in life, Haines said.

There is also a movement afoot, unrelated to the University of Guelph research, calling on the federal government to develop a national school food program. A UNICEF report ranked Canada 37th out of 41 countries on access to nutritious food for children.

"What we'd like to see is a national school food program where all kids from across the country know that they can go to school and get access to healthy food and eat it in an environment that teaches them about what healthy food means and about nutrition," Sasha McNicoll, co-ordinator at the Coalition for Healthy School Food, organized by the advocacy group Food Secure Canada, told CBC News.

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