Calories, low-fat, low-carb, high protein, glycaemic index. There are times when it is hard to keep track of what’s what when it comes to diets, dieting and nutrition.

One might often be forgiven for thinking that the food and diet industries were deliberately complicating matters so that we, the average punters who wants to lose some weight, are still beholden to their advice and products. Let’s not forget than these are industries that are worth literally billions of pounds.

For example, something that is low in fat and that is advertised and packaged as a ‘low fat’ option may well be high in sugar and more calorific than something that is high in fat. After all the Atkins diet advocates eating cheese and fatty foods to lose weight, and although it might well work in the short term and have its advocates in Hollywood, does that mean that it is a healthy diet to follow?

Foods fall in and out of fashion, as do diets and ways of exercising. It’s not surprising that many of us are confused and not quite sure what to believe.

And yet, in the precarious world of dieting and weight loss, there are certain benchmarks, which we feel we can rely on. Most obviously is weight.

If we get on the scales we can see whether we are heavier or lighter than the previous time that we got on those scales. That surely is a good indication of whether a diet is working? Well apparently not. We now recognise that muscle weighs more than fat, so someone who loses fat and gains muscle mass may actually get heavier. This is why many people now take issue with Body Mass Index (BMI) reading as an indication of healthiness or ideal weight.

Many athletes with body fat readings in single figures are considered obese if their BMI is calculated using their weight and height. Many bodybuilders would be considered morbidly or even super morbidly obese using this measuring method.

So what about calories- surely a calorie is constant unit? If it isn’t then how are we supposed to count them?

On the side of food packaging, the number of calories in the product is there to see. It also suggests what our calorie intake should be, 2000 for a woman and 2500 for a man. The experts suggest that, in order to lose weight, all we have to do is to either reduce our calorie intake or to burn more calories off in a day. If we do, they suggest, we will lose weight. It’s all pretty obvious isn’t it?

Well not really. A calorie is different depending on whether it is a carbohydrate, a fat or a protein. The body processes each type of calorie in a different way and this fact has big implications for someone who is trying to lose weight.

Here are the five reasons why one calorie of one type of foodstuff may be significantly different from one calorie of another: The body needs more energy to process protein than it does to process carbohydrates. It also needs more energy to process carbohydrates than it does fat. This means that someone eating a 2500 calorie diet of protein will add fewer calories than if they ate the same amount of calories of carbohydrates. Likewise 2500 calories of carbohydrate will add fewer calories than 2500 calories of fat. Yes it’s rather confusing isn’t it?

1. The body needs more energy to process protein than it does to process carbohydrates. It also needs more energy to process carbohydrates than it does fat. This means that someone eating a 2500 calorie diet of protein will add fewer calories than if they ate the same amount of calories of carbohydrates. Likewise 2500 calories of carbohydrate will add fewer calories than 2500 calories of fat. Yes it’s rather confusing isn’t it?
2. Eating fewer calories makes your body’s metabolism slow down, which in turn means that it stores fat rather than burns it. This is thought to be as a consequence of evolution- your body thinks that food is scare and therefore slows down- not good if you’re trying to burn off fat.
3. Eating a protein rich diet makes you less hungry than eating a carbohydrate rich diet. This means that if you start to eat more protein you will, more likely than not, eat less.
4. A high fibre diet reduces calorie intake. This is because fibre is not absorbed by the human body, which means that the calories you take in, if you eat a lot of fibre will not be added to your body. Also, like protein, a diet that is high in fibre reduces appetite, which means that you will end up eating less in a day.
5. The time of day at which you eat affects calorie intake. We burn calories more quickly in the morning. So if a person eats two identical meals, on in the morning and one in the evening he will absorb more calories in the evening.

 

There we have it then, proof that a calorie is not a fixed unit but has lots of shifting variables. It might make counting calories more difficult. It does not however make it less important.