You’ve probably heard of macronutrients in science or health class back in high school, but unless you continued to study nutrition beyond those classes, the likelihood of remembering what it is would probably be slim. Macronutrients, also known as macros, are nutrients needed by the body in order to function properly. They provide your body with energy in the form of calories, or kcals. There are three types of macronutrients to be aware of: carbohydrates, proteins, and fats.  

Each one of these macronutrients plays a specific role in how your body functions. Here’s how they work.


Carbohydrates create the main source of energy for your body, glucose, and are necessary for your brain and other organs to operate properly. They also help synthesize specific amino acids and allow consistent bowel movements. Not all carbohydrates are the same—there are two types of carbohydrates:

  • Simple: Simple carbohydrates are easy for your body to break down and turn into glucose, being made up of 1-2 sugar molecules. They’re typically found in sweet foods like honey, table sugar, syrup, milk, and fruit. Fiber, another simple carbohydrate, cannot be broken down by the body, but it helps with bowel movements and digestion.
  • Complex: Complex carbohydrates take more time to breakdown. These carbs come from savory foods, starches, and grains, along with other plant-based foods. 


Protein is the macronutrient that allows your body to grow, build, and repair tissues, and it protects lean body mass (muscles). It’s composed of amino acids, or the building blocks of protein, and is made up of two different types of amino acids: non-essential and essential. Non-essential amino acids aren’t required to be consumed through your diet because your body already makes this, while essential amino acids need to be consumed in order to get it. You can get protein through meat, poultry, fish, and other animal by-products or through plant sources like beans, lentils, nuts, and soy. 


Though fat usually gets a bad rep, it’s actually necessary to survive. Fat lets you store energy, cushion your organs, make certain hormones, absorb fat-soluble vitamins, and helps with cell membrane integrity. There are three types of fats: trans fat (fat that should be avoided), saturated fat (which increases cholesterol in large levels and is generally unhealthy), and unsaturated fat (healthy fat that decreases your risk for heart disease).

Macros and weight loss

Counting macros is a very effective way to help stay in line with your weight loss goals. I highly recommend using the app MyFitnessPal to help you keep track of your total calories and individual macros. Here’s a good method to start with your weight loss goals.

  1.   Find out what your total daily caloric intake should be 

There are several factors to consider when calculating your daily caloric requirements, depending on age, sex, weight, and activity level. Fortunately, there are many tools online which help calculate this for you. Just google “Calorie Calculator”, and many methods will be available at hand.

  1.   Find out individual macronutrients required to reach your caloric goal

Carbohydrates are 4 calories/gram; Proteins are 4 calories/gram; Fats are 9 calories/gram.

In general, a good starting point with respect to ratios of macronutrients are: 30% protein, 30% fats, and 40% carbs (30/30/40 breakdown).

  1.   Keep track of your weight

Purchase a scale. Stick to a strict daily calorie goal. If after 2 weeks, you have not lost any weight, decrease your total daily caloric intake by about 10-20% for the next 2 weeks.