What are Macros? Macronutrients and the Ketogenic Diet.

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If you are considering starting a Keto Diet, then you’ve probably heard references to ‘macros’ spoken in a nearly reverent way.  But, honestly, do you really know what macros are and why they are so all important?

P.S. If you are just starting keto, you should check out the Starting A Keto Diet Resources I’ve created right here on AdvatnageMeals.com.

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What are Macros?

“Macros” is short for macronutrients and these are the nutrients that our body needs in large amounts and that provide your body with its primary sources of calories – Research Link.  The three macronutrients are:

• Carbohydrates
• Fats
• Proteins

Basically, everything you eat that has calories will fit into one of these three macronutrient categories. 

In America, we usually measure each macro in grams.

How many calories are in each macro?

These macronutrients all provide calories that our body uses as fuel and for structural building blocks, though each macro doesn’t provide an equal amount of calories per gram as detailed by the USDA.

Carbs = 4 Calories per Gram

Fats = 9 Calories per Gram

Proteins = 4 Calories per Gram

There are other micronutrients (that our body needs but in small amounts like vitamins and minerals) but for now let’s focus on why macros are important in a Ketogenic Diet.

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#1 The Carbohydrates Macro

In a Ketogenic Diet, I suggest you eat no more than 25 net grams of carbohydrates per day.

Keeping your net carbs very low is the most important part of a ketogenic diet. To figure net carbs, look at a nutrition label and find the total carbs and the fiber as listed.

Total carbs minus fiber equals net carbs.

Depending on how much fiber you consume, that means that the carb macro will make up 5 to 10% of your total calorie intake.  This low carb diet will encourage your body to burn its stored body fat (more on that in the next section), and will in time make weight loss effortless.

But what is the Carb Macro?

In any form of eating, carbs are one of the three primary sources of calories for your body.

Carbs are the first source of energy that your body burns, for two reasons:

1. They are the easiest of the three macros to convert into energy.
2. All carbohydrates are converted into glucose which is then absorbed into the bloodstream.  Too much glucose in your blood is toxic, so your body wants to get your blood glucose level down quickly.

First, the glucose is shuttled into cells to be used immediately for energy. When the immediate energy need is met, but there is still too much glucose in your bloodstream, your body has to have a way control the glucose level in your bloodstream or you will die of glucose toxicity.

Some of that glucose is converted into glycogen and stored in your liver and muscles. Your body can store enough glycogen to fuel itself for about one or two days.

Any remaining glucose is converted into a more long-term, stable form of stored energy, body fat.

This evolutionary mechanism made sense thousands of years ago when carbs were relatively rare and just an occasional portion of our diets.  Store those carbs for leaner times!

However, in our modern world, carbs are not just an occasional treat. Sugary sweets are everywhere. And we’ve been taught that grains (which are very high in carbs) should be the foundation of our diet. But this just doesn’t match up with our biology!

In our current day reality, is it a surprise that we have way more carb calories than we can use in a day?

Is it a surprise that our body stores extra carbs everyday as body fat?

When your carb intake is low, your body dips into this extra stored fat and burns it for fuel.

When you constantly eat way too many carbs, this fat is never accessed because your body is always burning carbs for fuel.

What about your brain?

Glucose is your brain’s primary energy source. So don’t you need carbs to create glucose for your brain? Actually, no.

1. Your brain can also use ketones (a byproduct of a ketogenic diet) for a lot of its energy needs.
2. Your body can create glucose from fat and protein with a process called Gluconeogenesis as outlined by the NCBI.

Carbohydrates are not evil. They often contain important vitamins and minerals that are essential to good health. But carbs don’t need to be your primary source of calories as they are in the Standard American Diet (SAD).

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#2 Fats Macro

On a ketogenic diet, fat is going to make up the majority of the calories you eat in a day. If you’re just starting out, you want your fat intake to be about 70-80% of your calories.

If you’ve been in ketosis for a bit and your goal is to lose weight, you’ll take your dietary fat down to just enough to feel satisfied. That way, your body can burn stored body fat.

But isn’t fat bad for us?

In the summer of 1976 America’s fear of fat began, which was just a few years before our obesity epidemic began.

I am absolutely convinced that the government’s low fat diet recommendations led to America’s Obesity Epidemic.

Fat is an essential macronutrient for humans for both energy and structural function.

Being more energy dense than the other two macronutrients (9 calories per gram versus just 4 in the other two), fat is the best source of energy. You get much more “bang for your buck.”

The primary structural function of fat in our body is to form the membranes of each and every one of the billions of cells that make up our body, and it is vital for proper steroid and hormone production, which regulate all of the processes in our bodies.

Fat is not only essential, but it’s our preferred source of energy.

How do I know that it’s our preferred source of fuel?

Let’s think about this intuitively. When our body has excess energy, it stores that energy as body fat. Why would our body store its emergency energy supply in anything less than its preferred form?

Glucose (made from carbs) burns fast and hot and is followed by the inevitable crash when the fuel is gone. It’s great for immediate, high intensity energy needs, like sprinting. Fat burns slow and steady, making it an excellent fuel for normal, daily activities.

Also, we can only store enough glucose in our muscles and liver to fuel us for one to two days. But healthy, lean people carry enough in their fat stores to fuel them for about 3 months!

Even the most fat-phobic of government agencies recognize that fats are essential for good health.  Certain types of dietary fat provide your body linoleic and linolenic fatty acids, which we can’t survive without. These are commonly known as omega-3 and omega-6 fatty acids.

Why are these natural fatty acids “essential”?

They are essential because your body can’t function without them, and your body cannot make these fatty acids.

Your body must have the essential acids for a number of key survival mechanisms, including:

• Brain Development
• Controlling Inflammation
• Empowering Blood Clotting

And it’s not just omega-3 and omega-6 that are important. Remember all that fat your body is storing in its preferred fuel form? The vast majority of it is saturated and monounsaturated fat.

Dietary fat is essential for life.

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#3 Protein Macro

Protein is essential for life. Getting the right amount for your body is important for success on a Keto diet.

Keto is a moderate protein diet (not a high protein diet.) Your protein intake should be between 15-25% of your daily calorie intake.

Protein is the only macronutrient which our body cannot store in a conventional sense.  There is protein in your muscles, but it’s not really stored there; instead your muscles are made of protein.

It’s also the only one that doesn’t include ‘providing energy’ as one of its primary uses. Protein is primarily used as a building block for your body, from your largest muscles to elements of your blood.

Protein is only used for energy in extreme starvation situations or very intense prolonged exercise sessions like a marathon.

How much protein do you need?

Suggested ranges for protein intake run the gamut. Bodybuilders tout the need for huge amounts of protein while vegans will tell you the requirement is really very low. As with most things in life, the answer probably lies somewhere in the middle.

I have found that protein needs are highly individualized. Your needs will vary depending on age, gender, activity levels, stress, inflammation levels, and disease or recovery status.

From a Keto perspective, if you eat more protein than you need, your body can convert excess protein into glucose, which will raise your insulin level and knock you out of ketosis. That extra glucose can also be stored as fat if you don’t need it right away.

But if you eat too little protein, your body won’t have the essential building blocks required to repair and maintain your muscle mass and other body parts. If it needs to, your body will even start to cannibalize your muscle tissue for its protein needs.

How much protein should you eat on Keto?

When you first start a ketogenic diet, I suggest you try to keep your protein right around 20% of your daily calories. This will give most people enough protein for their body’s needs without taking in too much.

Some people function very well on a high protein ketogenic diet. If you start out at 20% of your calories from protein but feel that more would be good for you, try it.

If you have been eating on the high side for protein and struggle with hunger and are not losing weight, you may want to consider lowering your protein. Sometimes, too much protein will reduce ketone production.

To find my suggested minimum for protein, multiply your weight in pounds by 0.45 and make that your goal for protein. Get at least that much but try not to go over by a lot, at least not on a regular basis. If you have a large amount of weight to lose, you can multiply your goal weight by 0.45. Your ideal protein intake will be somewhere between the two figures.

If after a few days, this just doesn’t feel right to you, don’t force it. Some people need more protein for any number of reasons, and that’s ok!

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Ready to figure out your Keto Macros?

Now that you have a better understanding of what macros are, I encourage you to jump on over to my “What should my macros be on a Keto Diet?” article to figure out what your target should be for each macro.

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As always, if you found this article of value, please let me know in the comments below and consider sharing it far and wide.  Those things mean the world to me.

~ Angela

Disclaimer: While I have been keto for over a decade and have guided thousands of people through starting a keto diet, I am neither a licensed nutritionist nor medical professional. I never prescribe diets.  I only share my personal experiences and those of my clients for informational purposes only.  Nutrition details are provided for informational purposes only, and should not be considered medical nutritional data. You should consult your medical professional before making any major changes in the way you eat.