FOR years weight management has been about counting calories. But is taking a mathematical approach to weight loss the best answer?
With a plethora of calorie-tracking apps, nutritional information on food labels, and now menu boards and price tags with calorie counts, it’s hard not to be at least calorie-conscious.
Calories and kilojoules are common language*. With kilojoules (kJ) being the Australian preference, a kilojoule is a measure of how much energy people get from consuming a food or drink.
We get that in order to stay the same weight, we need to eat roughly the same amount of kilojoules as we burn. For the ‘average’ adult this is about 8700 kilojoules(roughly 2000 calories), if the surveys are correct. This magic number is widely used as an approximate figure for achieving and maintaining a healthy weight and as the basis of food labels and fast food menu boards.
Obviously 8700 kilojoules a day is an average. The actual amount of energy you need will vary depending on your age, gender, height, weight, weight history and physical activity level. In other words, your individual circumstances will dictate whether you need either more or less than 8700.
NOT CREATED EQUAL
Whether it’s an apple, a chocolate bar or a bowl of soup — a kilojoule is still a kilojoule, right? At least, that’s what dieters have been told for the past half-century. The problem is, not all kilojoules are created equal.
If you compare a plain croissant with jam and large full-fat latte to a small bowl of untoasted oat-based muesli with low-fat milk, fresh berries, and a dollop of yoghurt, served with two slices of toast with peanut butter, finished off with a cup of tea, it’s hard to believe that they are equal in kilojoules — roughly 2500 kJ (600 cal) for both meals.
Clearly this doesn’t appear right, especially given that scoffing a croissant and coffee (most likely on the run) will not give you that same full feeling as sitting down to a bowl of breakfast cereal, toast and fruit.
Different foods have varying affects on satiety (how full you feel after eating). In other words, your body responds differently to calories from different sources.
QUALITY VS QUANTITY
Let’s take a closer look at why the quality of kilojoules determines the quantity your body burns or stores. You’ll get so much more fibre in muesli, toast and fruit than in a croissant (13 grams versus 2 grams) and very few of the kilojoules would actually get absorbed because somewhere along the line your gut bacteria have burned them for their own energy source. Those that did would get absorbed very slowly causing your stomach to distend, sending signals to your brain that you were full.
As for carbohydrates, you may think that a bowl of cereal with toast and fruit is ‘carb heavy’ but it’s the types of carbs that matter most. The type of carb found in croissant and jam tend to have a higher gylcemic index (GI) meaning there’d be a high sugar spike. This would start a domino effect of high insulin and a cascade of hormonal responses that wreaks havoc on metabolism.