2. How To Calculate Macros To Lose Fat And Build Muscle

Macronutrients, or macros for short, are the second most important step in your diet setup. As you could read in my previous post, calories or more specifically their balance dictates if you lose or gain weight. On the other hand, macros will affect whether you will lose (or gain) more muscle or fat.

“Macro” means we need these nutrients in large amounts – tens to hundreds of grams per day. We distinguish three basic macronutrients – proteins, fats, and carbohydrates. So how to calculate macros to achieve our goals?

Before we dive into calculations of our individual macronutrient needs I think it is a good idea to learn a thing or two about them, their benefits, caloric content and of course the recommended amounts.


Proteins are made from amino acids out of which 9 are essential, which means that our bodies are unable to create them so we need to get them from food. These essential amino acids are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. The full amino acid profile is available only in meats so If you are a vegetarian or vegan you need a wide variety of plant-based protein sources to get them all.

Protein is probably the most discussed and researched macronutrient in the fitness world. From the fitness world perspective it’s mainly associated with muscle building, but not just that. It is the vital component for almost all tissues in our body. It has also two very useful properties for the dieter – it helps to protect us from muscle loss and is quite satiating.

Caloric content of protein – 4 kcal per gram.

Grilled salmon with vegetables

Salmon – great source of protein and fat

How Much Protein Do I Need In a Day?

The government recommended daily protein intake for healthy, nondieting person is around 10% – 15% of your daily caloric intake, which is 50 – 75 g for a 2000 kcal intake. This can be considered as a minimum intake for a healthy diet but is way too low for a person with physique-based goals. As you will see in the example calculation, our intake will be roughly double.

Recommended intake:

  • cutting: 1 – 1.3 g per lb of bodyweight (2.2 – 2.8 g per kg of bodyweight)
  • bulking: 0.8 – 1 g per lb of bodyweight (1.8 – 2.2 g per kg of bodyweight)

There is a difference between cutting and bulking because when you are cutting, you need more protein to protect lean tissue (muscle mass) and more protein also keeps you more satiated. When you are bulking you have an excess of calories so you don’t have to be afraid of losing muscle.


Fat is an essential nutrient that you should never completely eliminate from a diet. It is very important for proper hormonal function, skin, and hair health, body and organ insulation, and is necessary for absorption of fat soluble vitamins (A, D, E, K).

There are numerous types of fats like saturated and trans fats (considered unhealthy) and unsaturated fats (mono and polyunsaturated, considered healthy). All foods that contain fat contain a mix of all types.

Caloric content of fat – 9 kcal per gram.

Pouring olive oil in a bowl

Olive oil – one of the healthiest fats on the planet

How Much Fat Do I Need In a Day?

Recommended intake:

  • cutting: 15 – 25% of energy intake
  • bulking: 20 – 30% of energy intake

The difference between cutting and bulking is due to the fact that fat is the most calorically dense macronutrient. When we are in cutting phase we need fewer calories and decreasing fat intake can really make a difference to our energy intake. Be sure to don’t go below 0,25g/lb (0,5g/kg) because health.

I wouldn’t go lower than the low end of the recommendation above but you can certainly go higher if you have “fat tooth”:) If you have a feeling that you need more of it, up the fat intake for a few weeks and see how your body responds.


Carbs are the only macronutrient we can live without but I don’t recommend their complete elimination from a diet. They have a very big benefit of being the most easily accessible energy source for our bodies and they also taste good:)

They refill muscle glycogen, which is a primary energy source of our muscles and liver. This is really important for us since the largest part of our training will be powered by glycogen stores. Carbohydrates are also broken down into glucose, which is used by the brain.

Carbs are divided into two groups – simple and complex. This classification is based on their chemical structure and how fast are carbs absorbed by the body. From body composition perspective it doesn’t matter if you eat simple or complex carbs as long as calorie intake is adequate. From a health perspective, I don’t think it’s a good idea to get the majority of carbs from ice cream and pop-tarts.

Caloric content of carbohydrates – 4 kcal per gram.

Fruits and vegetables served in bowls and plates

Great sources of carbohydrates

How Many Carbs Do I Need In a Day?

Recommended intake:

  • cutting: the rest of energy intake
  • bulking: the rest of energy intake

As you can see carbs will fill up the remainder of our energy intake, after accounting for protein and fat. Here we will see the biggest difference between cutting and bulking phases.


Fiber is a type of carbohydrate that is indigestible or only partially digestible. There are two main types of fiber – soluble and insoluble.

Soluble fiber, which dissolves in water, is readily fermented in the colon into gases and physiologically active byproducts and can be prebiotic and viscous. Insoluble fiber, which does not dissolve in water, is metabolically inert and provides bulking, or it can be prebiotic and metabolically ferment in the large intestine. Bulking fibers absorb water as they move through the digestive system, easing defecation. (source)

Fiber is non-essential nutrient (you don’t need it to live) but it has many benefits:

  • increases satiety – it increases the volume of food without increasing caloric intake
  • stabilizes blood sugar levels – soluble fiber creates a gel-like substance which slows down the absorption of glucose and other nutrients
  • decreases cholesterol – both total and LDL
  • normalizes bowel movements – reduces constipation and improves the regularity of defecation
  • may reduce the risk of colon cancer
Chia seeds in a bowl

Chia seeds – great source of fiber and one of the healthiest foods on the planet

How Much Fiber Do I Need In a Day?

There are slight variances in lower and upper limit from various sources but the most recommended range is between 20 – 30 g (lower end for women, higher for men).

Summary And Example Calculation

Summary of recommended intakes for all macronutrients:

protein fat carbs
cutting 1 – 1.3 g per lb of bodyweight
(2.2 – 2.8 g per kg of bodyweight)
15 – 25% of energy intake the rest
bulking 0.8 – 1 g per lb of bodyweight
(1.8 – 2.2 g per kg of bodyweight)
20 – 30% of energy intake the rest


In this example calculation, I will use my caloric intakes calculated in calorie guide – 1570 kcal for cutting and 2350 kcal for bulking at bodyweight 137 lbs (62.1 kg).


  • bodyweight x recommended intake
  • cutting: between 137 x 1 = 137 g and 137 x 1.3 = 178 g
  • bulking: between 137 x 0.8 = 110 g and 137 x 1 = 137 g

I would use something like 150 g for cutting and 120 g for a bulking.


  • (caloric intake x fat recommended intake) / caloric content of fat per gram
  • cutting: between (1570 x 0,15) / 9 = 26 g and (1570 x 0,25) / 9 = 44 g
  • bulking: between (2350 x 0,20) / 9 = 52 g and (2350 x 0,30) / 9 = 78 g

I would use something like 45 g for cutting and 65 g for a bulking. I have a bit of a fat tooth, that’s why I went with the higher number for a cut.


  • (caloric intake – (calories from protein + calories from fat)) / caloric content of carbs per gram
  • cutting: (1570 – (150 x 4 + 45 x 9)) / 4 = 141 g
  • bulking: (2350 – (120 x 4 + 65 x 9)) / 4 = 321 g

To have a nice round number I would use 140 g for cutting and 320 g for bulking.

The final macros would look something like this:

protein fat carbs
cutting 150 g 45 g 140 g
bulking 120 g 65 g 320 g


Thank you for reading this a bit lengthy post, I hope you will find it helpful. If you have any questions or suggestions, please don’t hesitate to leave a comment.


  1. Arthur siew

    I find it quite difficult to measure how much calories and protein, carb and fats that I should eat in my diet. Can you suggest a way to measure them ?

    1. admin

      Excellent question Arthur. I should have mentioned that in the article.

      To find out macros in your food you can use nutrition labels on food you buy, or if there is no label (eg. you are in a restaurant) use some food tracker like myfitnesspal

      To track you calories you can again use myfitnesspal or do it like me and use excel sheet:)

      Thanks for the input.

  2. Dany J

    Nice post man! Very informative and useful!

    1. admin

      Thank you very much Danny J:)

  3. Xena

    WOW, very interesting! I didn’t realize that loose fat and gaining muscles was such a science. I though it was all about just lifting weights!

    How big difference do you think changing my diet make in my overall results for a female?

    1. Marek (Post author)

      Hi Xena:)

      Since I’ve tried both approaches I can say that it is possible to just lift weights and lose fat / build muscle. But it will take longer to see the results and you won’t be able to reach as good results as with more structured or in-depth approach (like the one in my article series). It may look a bit complicated but it really isn’t, just follow the steps:)

      It is a bit broad question but I will try to answer:) The change in your diet can work wonders! It all depends on where you are now, how committed you are to the change and how you set up your diet.

      Thanks for comment:)

  4. Nita

    I am amazed at how seemingly complicated loosing weight can be. No wonder for the life of me I struggle with my weight. Great article it sheds a light on all of my diets (and I’ve probably tried them all!) Best of everything to you and your website.


    1. Marek (Post author)

      Thank you Nita:)


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