02.What makes food fattening?
Even if your kids aren’t fat, you might still be surprised at just how many flab-forming kilojoules some of the foods specially aimed at kids can pack in. And on average Aussie kids really are getting fatter (see Childhood obesity).
While there are many contributing causes, lack of exercise doesn’t seem to be the main one. A recent study of schoolkids in NSW found that they’re now exercising more than they were around 10 years ago, yet still stacking on the weight. It seems they’re simply eating too much of the wrong foods.
We all know fast foods should only be an occasional treat (or a last resort for desperate parents), but the supermarket shelves are also loaded with products that’ll really pack on the kilos if your kids have too many of them too often.
And to make it worse, these products are often promoting a healthy image.
We’ve listed 10 (see The fat list). They’re not the only offenders, and many products out there are similar, if not the same — but they’ll give you some pointers to what to avoid.
What makes some foods more fattening than others?
If there were a simple answer there wouldn’t be so many fad diets. But you can get a good idea of how fattening a particular food is by looking at the energy (in kilojoules or Calories) per 100 g on the nutrition information panel. Nutritionists call this number the food’s energy density.
It seems we’re programmed to feel full when we’ve eaten a certain quantity of food, regardless of its energy value. So when foods pack in a lot of energy — when they’re energy-dense — it’s easy to get a lot of kilojoules from what looks like a very modest serving, and then not feel particularly full afterwards.
Foods with high energy density generally have a lot of fat and sugar (such as cakes, pastries and most processed snacks); those with low energy density typically contain more water and dietary fibre (most fruits and vegetables, for example).
Energy density comparison
Each of these plates has 500 kJ of food. Ferrero Nutella has a high energy density and the 500 kJ is provided by a small portion. The portion size is a little bigger for Steggles Chicken Nuggets, but a lot bigger for a tropical fruit salad, which has a low energy density typical of fruit and vegetables generally.
Tropical fruit salad: 234 g Nutella: 22.6 g Chicken nuggets: 47.2 g
Obviously other factors, such as how much we enjoy the food and the portion size, also influence the amount we eat, but our bodies haven’t evolved to cope with the energy-dense foods now so common on supermarket shelves.
Sweetened fizzy drinks, fruit drinks and fruit cordials are especially bad news nutritionally.
In the past they were a treat, something kids had at parties or other special occasions. Now many kids have them every day. But drinks don’t make you feel as full as solid foods do, so you can take in a lot of sugar (and the kilojoules that go with it) and hardly notice it.
And evidence is emerging that even artificially sweetened drinks without sugar can give you more of a liking for sweet foods and so contribute indirectly to you putting on weight.