2 HIGH PROTEIN

This macronutrient can help you stay fuller for longer

Of the three macronutrients – carbohydrates, fat and protein – protein is chemically the most complex. Fat and carbs are made entirely of carbon, hydrogen and oxygen atoms, just in a variety of different configurations, thus metabolising or storing them is energetically efficient.

Unlike fat and carbs, all protein in our body is there for a reason, either for building or for repair – there is no passive store of protein for a rainy day. So any excess protein that is not used immediately has to be metabolised into energy or converted into fat. Second, while protein is, like fat and carbs, primarily composed of carbon, hydrogen and oxygen, it also contains a significant amount of nitrogen. This nitrogen needs to be removed, so is secreted as urea, primarily in our urine, before the remaining chemical structure of the amino acids can be converted into energy or fat. This process takes a lot of words to explain, and even more energy to deliver. In fact, for every 100 calories of protein that we consume, we are only ever able to use 70 calories, with the other 30 calories needed to handle the protein. Thus, protein has a caloric availability of 70 per cent. All the protein calorie counts we see today are 30 per cent out!

By comparison, fat has a caloric availability of 98 per cent, meaning that to convert it to energy costs next to nothing, and hence why it is such an efficient long-term fuel store. As for carbs, it all depends on whether we are talking about the complex (90 per cent available) or refined (95 per cent available) variety. The difference in this availability is down to the presence of fibre, which we mostly cannot digest and therefore passes right through us.

Diets that are high in protein include the entire menagerie of ‘low carb, high fat’ diets, ranging in severity of carb restriction from Atkins to keto to carnivore, but are all universally high in protein, defined as 16 per cent or more of total daily intake. For all intents and purposes, they also encompass diets like gluten-free (with the exception for those suffering from coeliac disease) and paleo.

These diets work for many people trying to lose weight because protein, from a chemical perspective, takes longer to digest and takes more energy to metabolise, so is more satiating than fat or carbs. You feel fuller, you eat less, you lose weight.

It’s important to note that protein doesn’t only mean steaks! Fish, tofu, beans and nuts are all rich sources of protein, but without the saturated fat found in land-based animals. Consider including a wide range of protein in your diet.