If you're buying lunch from a fast-food outlet, don't assume that everything that claims to be "healthy" is. Eight pieces of sushi, from St Pierres, which advertises with the line "it's time to eat healthy", has more calories than a mince pie from Jesters.
Subway markets itself as "the undisputed leader in fast healthy food" but a foot-long version of six of the chain's 12 "classic subs" would provide more than than half a person's daily calorie requirements in one hit, when sauce and cheese is added.
Nutritionist Catherine Sissons said it was always worth looking into what "healthy" meant. She said pre-packaged boxes with eight pieces of sushi were more than most women would need to eat and did not contain enough protein to be a balanced meal.
"If you choose sushi, go for the ones with protein laid on top of the rice or add in some sashimi or edamame beans on the side. Donburi, a mixture of teriyaki chicken and rice with salad, is a good combination. Be aware of the rice portion and find out how much is right for you."
A woman with a sedentary lifestyle needs about 1,800 calories and a man needs about 2300 a day. A foot-long Three Pepper Chicken sub from Subway contains 814 calories before any extra sauces or cheese are added.
Cheddar cheese adds another 80 calories to a foot-long sandwich, and ranch dressing adds almost 200. Sissons said Subway did not include enough salad.
"McDonald's salads are the best option if you want less processed and more fresh ingredients. A meatball foot-long has more calories and fat than a Big Mac."
Salad bars were good options but could catch people out with added nuts and seeds, she said. "Beware of salads that have too large a carbohydrate portion, such as roast vegetable salads. Carbohydrates need to make up no more than a quarter of your whole portion," said Sissons.
Healthy Food Guide nutritionist Claire Turnbull said people should look for a lunch with vegetables. "Go for wholegrain carbohydrates such as brown rice or wholegrain bread.
"Make sure you're getting some protein from chicken, fish, lean meat or eggs, as well as a little healthy fat by including avocado."
For a lunch under $15, Turnbull recommended a Tank Thai Chicken Salad, Habitual Fix's Mexicano Salad, Subway's Roasted Chicken Salad and Pita Pit's Chick'n Fala made as a salad, or sushi with a side of edamame beans.
Sissons said people should not be too hung up on calorie counting.
"Too many people worry about calories without thinking about food as fuel and what nutrients it is providing. Eating foods that have a greater variety of vitamins, minerals, amino acids, protein and supply some carbohydrate is essential for a healthy metabolism and for the body to burn fat."
Sissons' top cheap lunch picks for a cheap lunch were a Naked Burrito from Mad Mex or snack pack-size sushi.