Coming up with lunchbox ideas day after day, year after year, can take its toll on the imagination. Fruit juice poppers are one of those convenient items that you can buy in bulk, keep in the cupboard, fridge or freezer, and pop in the lunchbox as a sweet, hydrating treat. It's kind of like fruit in a box! Except, well, it's not.

Juice comes from fruit, so it must be healthy, right?

Fruit juice tends to have a healthy image, and 100% juice can give you valuable nutrients such as vitamin C and folate. But it contains all the sugar of fresh fruit without the fibre, and Australian dietary guidelines advise we only occasionally substitute 100% juice for fruit pieces as counting towards the recommended two serves a day. A serve of juice is defined as 125mL (half a cup), and most poppers contain double this amount.

Watch out for added sugar

Don't confuse fruit juice with fruit drinks. Fruit drinks contain minimal juice (generally less than 40%) and have added sugar, and for the most part should have the status of treats only. One brand we tested contained more than six teaspoons (30.5g) of sugars in a 250mL pack of juice – that's more than the recommended adult intake, as recently revised  by the World Health Organization, and nearly as much as a 330mL can of Coca Cola.

Like soft drinks, sugar-sweetened fruit drinks are packed with kilojoules and tend to offer few nutrients. There's mounting evidence that drinking sugar-sweetened beverages is associated with an increased risk of weight gain, and that they contribute to dental decay. Drinks that are both sugary and acidic – such as fizzy and energy drinks, as well as fruit juices and fruit drinks – tend to be the worst offenders.

If you're after the convenience of a popper, choose one with no added sugar.

Other things to consider

Size

Juice poppers come in a range of sizes, generally from 125mL to 300mL. A serve of juice is defined as 125mL (half a cup), and most poppers we reviewed contained twice this amount.

Artificial colours

A priority for many parents when choosing food and drinks for their kids is that they're free of artificial additives. The following artificial colours have been red-flagged for kids showing signs of hyperactivity:

  • sunset yellow FCF (additive number 110)
  • quinoline yellow (104)
  • carmoisine (122)
  • allura red AC (129)
  • tartrazine (102)
  • ponceau 4R (124).

Of the poppers we reviewed, several brands contained one or more of these colours.

In 2007, researchers at the University of Southampton in the UK linked combinations of these colours and the preservative sodium benzoate to increased hyperactivity in some children. Subsequent reviews by the European Food Safety Authority and US Food and Drug Administration concluded that a causal link wasn't substantiated by the available evidence.

Despite this, it's now mandatory in the European Union for food and drinks containing any of these six colours to be labelled with the warning: "May have an adverse effect on activity and attention in children."

The Australian food regulator FSANZ advises that its 2006 study of added colours found Australian food manufacturers use these colours at much lower levels than those of the Southampton study.

What about water?

As any dietitian will tell you, water is the best everyday drink for children. The occasional 100% fruit juice is fine, however, and can add variety to their lunchbox. Choose a small popper and give your child a bottle of water as well for extra hydration. Or make up your own juice bottle with a 125mL serve of juice, and dilute with water to provide better hydration.

Cost

The juice poppers we reviewed ranged in price from $0.13 to $1.00 per 100mL.