What Are Macronutrients?

“Macronutrient” is a blanket term for a nutrient that provides the body with energy (calories). The four main macros being:

  • Protein
  • Dietary fat
  • Carbohydrates
  • Alcohol

Out of these four, fat, protein, and carbs are essential for life and bodily processes, whereas alcohol is non-essential (although calorically dense, thus a macronutrient).

Let’s take a closer look at the three essential macronutrients and their importance…


Proteins are molecules consisting of one or multiple amino acids, bound together with peptide chains. Amino acids come in three different categories; essential (9), conditionally non-essential (7), and non-essential (4). The term “complete protein” is used when some food has all 20 of them. Animal proteins (meat, milk, cheese, eggs) are all considered complete, whereas many plant-based proteins (legumes, seeds, grains, vegetables) are not (however they can be combined in a same meal to make a complete protein source).

Some basic functions of proteins include;

  • maintenance and growth of lean muscle mass, connective tissue, and bones
  • acting as neurotransmitters in the brain
  • transportation and storage of bodily molecules
  • hormone creation (insulin, secretin, etc)
  • enzyme synthesis

Dietary Fat

Dietary fatty-acids or triglycerides (fancier word) are esters of the fatty-acid chains, often separated into the following three types:

  • Monounsaturated fatty-acids (MUFAs)
  • Polyunsaturated fatty-acids (PUFAs)
  • Saturated fatty-acids (SFAs)

These fats are found in different ratios from our everyday basic foods, most red meats and tropical oils for example are higher in saturated fat and low in PUFAs, whereas seed and vegetable oils tend to be higher in PUFAs with lower amounts of saturated fat. Foods high in MUFAs include olive oil, avocados, argan oil and Macadamia nuts.

These three types of fats also branch down into even more specific types – but most notably – remember that the polyunsaturated fats are identified with omega (ω) numbering, such as;

  • Omega-3’s
  • Omega-6’s
  • Omega-7’s
  • Omega-9’s

The benefits of fatty-acids are numerous, for one, fats are the most nutritious (9kcal/gram) macronutrient, which according to some experts allowed the human species to develop bigger brains than other mammals. Aside from just being an energy source, fats serve as signaling molecules between cells and hormones, are necessary for creation of all steroid hormones, protect and “insulate” bodily organs, and are vital components in normal cell functioning. Out of the three macronutrients – completely omitting from dietary fat would yield the biggest health problems, with this view it could be labeled as the most important macronutrient for human survival.

It’s also worth mentioning that some vitamins are fat-soluble (A, D, E, and K2) and thus can only be absorbed by the body with proper intake of dietary fat.


Carbohydrates (CHO) consist of carbon, hydrogen, and oxygen. They are the most readily-available form of energy for the human body, and are often divided into groups of;

  • Sugars (found in table sugar, fruits, and some vegetables)
  • Starches (found mostly in grains and root vegetables)
  • Fiber (found in many foods but highest in whole grains, nuts, fruits, and legumes)

Carbs are often simplified and separated into two categories; simple carbohydrates and complex carbohydrates. The simple type being the kind that is rapidly absorbed to the bloodstream and complex being something that’s released to the bloodstream in a slower manner. The key here is to remember that all carbohydrates (with the exception of insoluble fibers) will be converted to the simplest form of sugar (glucose) before it enters the bloodstream, some just convert faster than others.

Carbohydrates are necessary part of;

  • Fueling the metabolic processes of nearly all of the bodily cells
  • Storage of energy in muscle tissue and liver (muscle and liver glycocen)
  • Providing energy (ATP) for the central nervous system and endocrine system