Macro friendly, macro splits, macro tracking: “Macros” are everywhere in nutrition. But what are macros, and why are they so important?
As usual, this is where nutritionist and nutrition researcher Richie Kirwan comes in to save the day. Macros in terms we can understand? Go on then.
What are macros?
As is often the case in nutrition, there’s an abbreviation in our midst. It won’t surprise you to learn that “macros” is short for macronutrients and comes from the Greek makro, meaning “large”.
Macronutrients are the nutrients we consume in large quantities and are usually measured in grams. There are three main macronutrients important to our diets: protein, carbohydrates and fats. (Technically speaking, alcohol is also a macronutrient, but it doesn’t serve an important role in a well-balanced diet.)
Micronutrients are the smaller siblings of macronutrients. They are smaller nutrients like vitamins and minerals and are generally measured in milligrams or even micrograms.
First up, everyone’s favourite macro. Protein comes from the Greek word protos, meaning “of prime importance”. It’s kind of a big deal, mostly because of the role it plays in several processes in your body. One gram of protein provides you with four calories of energy.
Proteins are made of long chains of smaller molecules called amino acids. They are called “amino” acids because all amino acids contain an amine group, which contains nitrogen; protein is the only macronutrient that contains nitrogen.
There are 22 amino acids in human nutrition. Nine of these are considered “essential” as the human body can’t make them itself and we must get them from our diets.
Protein is necessary for the growth and repair of various tissues. Essentially, your body is made up of protein in different forms. It’s used to form your hair, skin, bones, ligaments and tendons and muscle. The structural function of protein is incredibly important.
Protein is also essential for the formation of enzymes, hormones, antibodies and other signalling chemicals in your body. All of these are proteins with very specific chemical functions. Our bodies are complex protein-based machines, and protein is required for so much more than simply building muscle.
Most whole foods have some amount of protein in them, but the amounts vary. 100g of lean steak can have about 25g of protein, whereas 100g of broccoli has about 3g of protein. One of the highest quality sources of protein available to us is milk protein, which includes whey and casein. These are both easy to digest and full of essential amino acids. Other options include eggs, fish, and lean meats. Or if you follow a plant-based diet, then tofu (soy) is a great option.