What Are Macronutrients?

In order to understand nutrition one needs to comprehend the fundamentals. Learning the three macronutrients and what they’re used for is a great place to start. This will help you to further your knowledge in nutrition and allow you to understand the principles of whichever type of diet you choose.

The Big Three

  • Fat

  • Carbohydrate

  • Protein


There are several different types of fat, but for the simplicity of this article I want you to focus on only two: saturated and unsaturated.

Saturated Fat

What is it?

The term “saturated” refers to its chemical structure, being that all carbon bonds are full, but no one actually cares about that. For the past decade or so saturated fat has become one of the several no-no’s of  good eating habits. Is this warranted? As you’ll find with other articles on this site, such as Flexible Dieting. No foods are inherently good or bad.

A current review [1], has shown the saturated fat scare to be incredibly overrated and the initial outcry was based on poorly controlled epidemiologic studies. In moderation, especially combined with other healthy lifestyle factors, saturated fat is not the bad guy. Saturated fat has actually been associated with an increase in testosterone levels, [2], so avoid it all together is not recommended.

Where is it found?

Most saturated fats are solid at room temperature and can be found in various types of meat, such as chicken, steak, beef, fish, eggs, bacon & sausage. Each of these meats differ in their fat content. Other sources of saturated fat include dairy products, such as milk, cheese and ice cream. These too can vary greatly depending on the type and several dairy products are offered fat-free.

Unsaturated Fat

These fats have been far less demonized, frequently referred to as “healthy” fats, but as stated earlier this is misleading at best. These fats are typically liquid at room temperature and include oils, like canola and olive oil. This can further be broken down into polyunsaturated fats and monounsaturated fats, which will be found on the food label.

*Note: majority of foods do not contain only saturated or unsaturated fat, but a combination of the two, like listed on this label.

Basic Role In The Body

*Cell Structure-conserve body heat, protect organs

*Metabolic Regulation-cholesterol formation, hormone production

*Energy Source-predominant at rest, energy of metabolic processes


If you’re following the flexible dieting approach I do not think it’s incredibly important which type of fat you consume. Remember, this means 80-90 percent of your intake is coming from whole-foods. Those “bulking” may need to keep a closer eye on the saturated fat number, as adverse conditions would most likely show under these conditions.

I generally recommend an intake of 0.3-0.5 grams/lb. body weight for most individuals. This also ranges from 20-30 percent of overall calories. The range you choose should be based on your personal food preference and trial and error on exercise performance.

Common Sources of Fat

Peanut/almond/regular butter, nuts, high-fat dairy, vegetable oil added to processed foods, high-fat meats, salad dressings & oils added to meals. 


Carbs are bad! Run, run, run away! In the 90′s fat was the bad guy, now it seems that the ball has been passed to carbohydrates. As you’ll find out in Meal Frequency and Energy Balance no single nutrient can solely cause obesity, but rather an overall positive energy balance will result in weight gain regardless of what is consumed. Like fat, there are several kinds of carbohydrates, but I will break them down into the major two forms: simple and complex.

Simple Carbohydrates

These as also known as sugars, such as lactose (milk sugar), sucrose (table sugar), fructose (fruit sugar) and others. Simple carbs have also gotten an undeserved reputation as being unhealthy. The main argument usually stems from their ability to rapidly increase blood sugar, as you’ll find in Issues with the Glycemic Index this is a misunderstood concept.

Some sugars such as those found in soda, pop tarts, cereal and other processed foods may not come with additional nutrients. This does not make them “bad” foods, but rather foods that shouldn't make up the bulk of our carbohydrate intake. They can still be consumed on a semi-regular basis. Other sugars such as the ones found in fruit and milk are accompanied by other micronutrients and in fruits case even fiber.

Complex Carbohydrates

These are also known as starches and can be found in foods such as whole grain bread, pasta, oatmeal, potatoes, vegetables and rice. These are often time referred to as “good carbs” but the goodness of carbohydrate is more determined by the context of your entire diet rather than a single serving. These carbs will generally be more filling and packed with micronutrients, so they should make up majority of your intake, but not necessarily all.

Basic Role In The Body

*Supply Energy-brain, central nervous system, major fuel source during high intensity exercise.


Carbohydrate tolerance is incredibly variable depending on genetics and activity factor. It’s very difficult to give a broad range for individuals to follow, but as a good rule of thumb if one is exercising, carbohydrate content could make up 40-60% of caloric intake. Again, this is highly variable depending on the individual. An endurance runner will have incredibly high carbohydrate needs, while an individual who works a desk job and exercises for 4-5 hours a week will have low-moderate carbohydrate needs. Although fiber is not mentioned in this article, I’d also recommend a baseline of 15 grams of fiber/1,000 calories consumed for decreasing hunger and general health.

Common Sources of Carbohydrates

Bread, oatmeal, cereal, rice/pasta, table sugar, fruit, sport drinks/soda, pancakes!


You begin to feel bad for all these macronutrients, it seems like one way or another they all get picked on. In High Protein Diets Damage Kidneys you’ll find out that there has never been any research showing adverse effects on kidney function during high protein diets with individuals with normal functioning kidneys. [3] For our purpose we will break protein down into two components: complete and incomplete.

Complete Protein

Complete proteins contain all nine essential amino acids, these are the amino acids that our body cannot make on its own, so it’s imperative we obtain them from the diet (amino acids are just broken down protein.) Animal products are great sources of complete protein, such as beef, chicken, fish, pork and dairy products.

Incomplete Protein

Incomplete proteins are “incomplete” because they lack one or more of the essential amino acids. This does not mean they are not counted or used by the body, but that they are less important. These are typically found in much smaller amounts in foods such as grains, vegetables and some processed foods. Some sources such as beans and nuts are quite high in protein.

Basic Role In The Body

*Formation of Body Tissues-muscle 

*Regulation of Metabolism- enzyme and hormone formation

*Water Balance

*Acid-Base Balance

*Immune Function


Note that digestion and utilization of food is a long process and foods are rarely consumed in isolation. Take a chicken sandwich from Subway as example. On the sandwich you will have chicken (complete protein), cheese (complete protein), bread (incomplete protein) and vegetables (incomplete protein) overall you may consume 50 grams of protein with 40 grams complete from a complete source. I do not feel it’s necessary to count them separately for this reason as long as majority of your intake is coming from complete sources.

Recommended intake will greatly vary depending on who you ask, but for those involved in exercise and looking to lose fat, build muscle or gain strength a recommend an intake of 0.75-1.25 grams/lb. of body weight is a good starting place.

A important thing to note about protein needs is that they’re based off lean body mass, since fat tissue isn’t very metabolically active. This means in an individual is severely overweight the average of 1g/lb. of body weight is not necessary. You’ll have to be objective about your body fat level or actually get it tested and dose your protein accordingly. In general, the leaner the individual the higher relative protein needs.

Common Sources of Protein

Meat (chicken, beef, steak, fish, eggs), dairy (including protein powders such as whey & casein)

 Wrapping Up

Hopefully this post was a great starting point for you in the quest to learn more about nutrition. Knowing the three macronutrients, their roles in the body, and dispelling myths about each one will assist you no matter which type of diet protocol you choose. Things certainly get more complicated than this, but without this prerequisite knowledge it is easy to fall into the lure of sexy fad diets. Understand that not any nutrient is inherently good or bad, but rather obtain the knowledge on how to use them properly so you can have the healthiest and most suitable diet for your needs.


1. Volek, J. S. Testosterone and cortisol in relationship to dietary nutrients and resistance exercise. Journal of Applied Physiology. 1996

2.Volek, Jeff S. “Testosterone and cortisol in relationship to dietary nutrients and resistance exercise.” Journal of Applied Physiology. 1996

3. Martin WF, Armstrong LE, Rodriguez NR. Dietary protein intake and renal function.Nutr Metab. 2005;2:25.