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Macronutrients 101

Updated: Mar 9

What are the 5 macronutrients?

  1. Protein

  2. Carbohydrate

  3. Fat

  4. Fiber

  5. Alcohol

The macronutrient composition of our diet has a massive impact on health, wellbeing, and our ability to comply with a diet, whether it’s at our caloric baseline, a deficit or a surplus. Understanding how macros interact with the body is crucial to understanding how to manipulate calories effectively, so let’s look further into each to understand precisely how they work.


Forms the building blocks of muscle

  • Muscle optimizes good health and our body composition

  • Adequate consumption of protein along with resistance training while we diet will prevent muscle catabolism

  • Protein is an essential macronutrient

  • What is an essential macronutrient?

  • Essential macros are needed by the body to function normally but cannot produce on its own

  • If we don’t consume adequate amounts of protein, our body will find protein elsewhere

  • What happens if we do not eat enough protein?

  • In a severe protein deficit, the body will start to break down muscle to provide protein for other essential bodily functions.

  • When it runs out of muscle, it will go after organs, and when it runs out of organs, that will inevitably result in death.

  • 20 different amino acids used by the human body

  • 9 of them are essential

  • Essential amino acids means the body cannot make them, they must be eaten

  • Essential Amino acids

  • Histidine

  • Lysine

  • Methionine

  • Phenylalanine

  • Threonine

  • Tryptophan

  • Isoleucine

  • Leucine

  • Valine

  • Non-essential Amino Acids

  • Alanine

  • Asparagine

  • Aspartic acid

  • Glutamic acid

  • Proteins are broken down by digestive enzymes

  • Enzymes breaking down food into nutrients

  • Carbohydrates

  • Amylase

  • Maltase

  • Lactase

  • Glucose

  • Proteins

  • Pepsin

  • Protease-trypsin

  • Peptidase

  • Amino acids

  • Fats

  • Lipase

  • Fatty acids & glycerol

  • How do we get protein?

  • Not all proteins are equivalent

  • Measure protein quality 1 of 2 ways

  • Bioavailable (biological) Value = BV

  • Protein Digestibility Corrected Amino Acid Score = PDCAAS

  • Bioavailable Value

  • The biological value provides a measurement of how efficient the body utilizes protein consumed in the diet.

  • A food with a high value correlates to a high supply of the essential amino acids.

  • Animal sources typically possess a higher biological value than vegetable sources due to the vegetable source’s lack of one or more of the essential amino acids.

  • Protein Digestibility Corrected Amino Acid Score

  • PDCAAS measures the amino acid profile of a protein versus an ideal source for the human body. 

  • Protein that provides the right proportion of the various amino acids when broken down through digestion

  • What about veggies and grains as protein sources?

  • The key is what triggers Muscle Protein Syntheses…Leucine

  • Vegan protein sources are inferior to animal proteins for improving body composition because they do not contain the full spectrum of essential amino acids, and most do not contain leucine.

  • Vegan protein sources are considered incomplete


1 or 2 primary sources of fuel for the body

  • While all food is energy, carbohydrates provide the most readily available form of energy in the human diet

  • Types of Carbs

  • Monosaccharides – the simplest of carbs, one sugar

  • Fructose – sugar in fruits

  • Glucose – THE primary fuel source of the body.

  • Disaccharides – “double sugars”

  • Lactose – sugar in dairy

  • Sucrose – table sugar

  • Polysaccharides and Oligosaccharides – these combine monosaccharides into special arrangements resulting in complex carbohydrates

  • True or False: Carbs are needed in order for the body to properly function?

  • False – the body is capable of running on fat as energy and smart enough to be able to turn proteins into glucose through a process known as gluconeogenesis.

  • Non-Essential doesn’t make carbs unimportant.   Carbs play several key roles when it comes to energy and muscle hypertrophy.  Without adequate carbs, you will struggle to stay energized, struggle during workouts, and building muscle without carbs is possible but VERY inefficient

  • Carbs are classified based on their impact on the human body and measured by 1 of 2 ways:

  • Glycemic Index, or GI

  • Measures relative impact on blood sugar levels of a given carb vs pure glucose

  • 100% = carbs become fuel as readily as glucose (glucose is body’s natural fuel source).

  • <100% = fuel source is relatively slower than glucose

  • More complex a carb will slow down how long it takes to be broken down into glucose in blood, thus lower the GI of that carb will be

  • Glycemic Load

  • Looks at how a carb will impact the body by elevating blood sugar

  • Higher GL = More blood sugar expected


Is it a carb, or its own macro?

  • Fiber serves a crucial role in keeping our digestive system healthy

  • Insoluble Fiber – indigestible portion of plants we eat that does not dissolve in water.  Instead of being digested, insoluble fibers increase bulk, soften stool, and shorten transit time through the gastrointestinal tract.

  • Soluble Fiber – Dissolves in water, helps to slow the emptying of the stomach (increased fullness).  Also helps to lower cholesterol and regulates blood sugar levels.

  • Soluble Fiber will either absorb water and become gel or it dissolves in water and reaches intestine and are digested by bacteria. 

  • Soluble Fiber

  • Dissolve in water and slow down digestion to give you that “full feeling”.

  • Oatmeal

  • Lentils

  • Apples

  • Insoluble Fiber

  • Add bulk to diet and help with constipation, have that “laxative” benefit

  • Barley

  • Couscous

  • Brown rice

Key Points to Remember on Carbs

  1. Carbs are our best source of energy

  2. Carbs are necessary for maximizing our muscle protein synthesis

  3. Carbs can be adjusted to benefit insulin resistant people

  4. Carbs are easily adjusted in a nutrition plan based on activity

  5. Carbs keep us feeling full

  6. Carbs fuel good bacteria and keep our plumbing running “smoothly”


Fat is the #2 Primary fuel source in the body!!!

  • Most dietary fat is slow digesting and take the long journey through the digestive track. Thus, fat is the primary mechanism for storing long term energy in the body.

  • Fat’s do well for energizing the body through low to moderate intensity exercise

  • When glycogen is depleted, fat becomes the primary source of fuel during endurance activities.  

Fats break down into 2 categories:

  • Saturated

  • Saturated fats tend to come from animal sources

  • Saturated fats are solid at room temp

  • Not all saturated fats are not unhealthy

  • Unsaturated

  • Unsaturated fats tend to come from plant and fish sources

  • Unsaturated fats are liquid at room temp

  • Not all unsaturated fats are healthy

  • Can be split into monounsaturated and polyunsaturated fats

  • Monosaturated

  • They have a single carbon-to-carbon double bond in their molecular structure

  • Sources: olive oil, peanut oil, nuts & avocado

  • Polyunsaturated

  • They have 2+ double carbon bonds

  • Are essential fats and can’t be produced by the body

  • Fall into 2 categories: Omega-3 & Omega-6

  • Omega 6 come from vegetable oils

  • Omega 3 primarily comes from fish oil

  • Omega 6 are overconsumed in the Western Diet

  • Diet should include a 1:1 ratio of each Omega

  • Trans Fats

  • Trans fat comes when hydrogen is added to unsaturated fat – taking a previously liquid fat and turning it into a solid fat at room temp.

  • There are no naturally high sources of trans fats

  • Linked to health problems such as cholesterol by driving down the “good” HDL and driving up the “bad” LDL

  • Linked to increased inflammation and negative heart health outcomes

  • Best to avoid trans fats when at all possible

  • If you see hydrogenated it is a trans fat regardless if it is followed by a vegetable oil, i.e. hydrogenated canola oil


  • Triglyceride consists of three fatty acids linked together by a glycerol

  • Triglyceride is the form that fat takes in the blood and is also the form of fat that provides energy to our cells


Gram for gram, alcohol is a very dense source of calories

  • There is NO recommended amount of alcohol

  • The body has NO biological use for alcohol

Our body has no ability to store alcohol, thus the calories are preferentially metabolized -it will be the 1st fuel the body will use

  • There is no circumstance where you want to prevent the body from burning carbs AND fats at the same time

  • Alcohol comes with other negative side effects: 

  • Reduces inhibition, making it hard to stick to a nutrition plan

  • Disrupts restorative sleep limiting the body’s ability to adequately recover and repair

Want to know how to calculate your individual macros for fat loss and healthy body composition?  Check out my online course- it’s a printable course with handouts with a video component and takes about 90 minutes to complete!   It's 50% off ONLY FOR THE MONTH OF MARCH!!!  Click HERE for details!

Keep Moving Forward 😊 Sarah

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