Calculating Macronutrient Distributions

Disclaimer: The use and efficacy of this style of macronutrient / Calorie calculation is predicated on your individual maturity and capacity to track dietary intake. This is a skill in and of itself and is not appropriate for all people. Those with a history of disordered eating or eating disorders are better served using other methods of dietary planning and should seek the guidance of a registered dietitian. Further, this macronutrient distribution guide assumes the reader is free from any chronic illness or metabolic considerations. Anyone with clinical considerations should follow the guidance of a registered dietitian.

Estimating Caloric Requirements

The basal metabolic rate (BMR) is the number of Calories required to maintain your current weight during absolute rest (sleep). This number can be predicted by using a variety of metabolic equations (each having particular strengths or weaknesses). In the case of this example, we will use the Harris-Benedict equation.

Harris-Benedict Equation

Males: BMR = 66 + (6.23 x weight in lbs) + (12.7 x height in inches) – (6.8 x age in years)

Females: BMR = 655 + (4.35 x weight in lbs) + (4.7 x height in inches) – (4.7 x age in years)

We now multiply the BMR by a coefficient which represents your (estimated) average daily physical activity level. This number accounts for the additional Calories required to maintain your weight when we consider your activities of daily living. This is your total daily energy expenditure (TDEE).

Average Daily Physical Activity Level (coefficient):

1.2 = Sedentary (desk job, little formal exercise)

1.375 = Lightly Active (light daily activity & light exercise 1-3 days a week)

1.55 = Moderately Active (moderate daily activity & moderate exercise 3-5 days a week)

1.725 = Very Active (physically demanding lifestyle & hard exercise 6-7 days a week)

1.9 = Extremely Active (athlete in ENDURANCE training or VERY HARD physical job)

Example – A 26 year old male who is six feet tall would like to weigh 200 lbs. He is moderately active. His estimated total daily energy expenditure at his goal weight would be:

TDEE = (66 + (6.23 x 200) + (12.7 x 72) – (6.8 x 26)) x 1.55

TDEE = (66 + 1246 + 914.4 – 176.8) x 1.55

TDEE = 3177 Calories

It’s important to keep in mind that all of these numbers are estimates. The final number of Calories you end up consuming in reality may be somewhat more or less than what was calculated; however, this will provide a relatively useful ballpark. Compare your current average caloric intake to your estimated requirements and then slowly add/subtract the difference. This process may take many months to achieve but in this case slower tends to be better. A controlled rate of Calorie increases or decreases produces far better outcomes for leanness or muscle retention (depending if you are attempting to gain or lose weight). A general guideline is to add or subtract 250 – 500 Calories to or from your current and hold it at that new total until you see your weight plateau once again. From there, add or subtract another pocket of Calories and repeat the process.

Macronutrient Distribution

There are certain benchmarks for macronutrient distribution one should strive for, especially when becoming physically active. Whether you are trying to lose body fat or gain muscle, there is a minimum level of protein and fat intake to account for. This is because protein is the main nutrient used to grow and repair the muscle used during exercise and fat is an essential nutrient for creating and maintaining healthy levels of naturally occurring hormones (among other things). Without careful consideration for protein and fat intake, progress toward either goal may stall. Carbohydrates also have certain benchmarks (usually a baseline or minimum intake) which should be met in order to prevent the other two nutrients from being used for energy instead of their “manufacturing” roles.

Protein – Deciding on how much protein to consume is typically affected by the type and frequency of exercise or activities of daily living you are performing. For example, consuming higher levels of protein becomes more important as your lifestyle becomes more physically demanding. Calculating your estimated dietary protein intake (in grams) is usually a function of multiplying your lean body mass (LBM) (in kilograms) by a specific coefficient depending on the level of physical activity you engage in.

Estimated Protein Requirements (coefficient):

0.8 = Sedentary

1.2 – 1.4 = Endurance training and/or muscle maintenance

1.5 – 1.7 = General resistance training

1.7 – 2.0 = Heavy resistance training and/or high intensity athletic training

≥2.0 = Maximal muscle gain and/or maintaining muscle in Calorie deficit

Fat – Dietary fat is required for maintaining many processes within the body. In recent decades, most people have critically reduced their dietary fat intake because they associate ingesting dietary fat with the accumulation of fat on the body. This simply isn’t the case. Consuming a surplus of Calories above that which would maintain your weight, over a long period of time, is the true culprit. A general recommendation for the amount of dietary fat (in grams) to consume per day would be anywhere from 20 – 35% of your TDEE from healthy sources.

Example – A TDEE of 3177 Calories would have an approximate recommended dietary fat consumption range of 70 grams (635 Calories) – 124 grams (1112 Calories) per day.

Carbohydrate – Carbohydrates are one of your primary fuel sources during exercise and also protect against the breakdown of dietary protein for energy. Use them as caloric filler once you’ve established how many Calories you’ll need to denote to both protein and fat.

Example: A 26 year old male who is six feet tall would like to weigh 200 lbs. He is moderately active. His estimated total daily energy expenditure at his goal weight would be 3177 Calories. An example of his macronutrient distribution would be as follows:

Step 1: Convert body weight (in lbs.) to kilograms (kg).

·      200 lbs ÷ 2.2 = 90.9 kg.

Step 2: Protein calculation.

·      Protein = 4 Calories per gram.

·      90.9 kg x 1.5 grams of protein (moderately active) = 136 grams of protein.

·      136 grams of protein x 4 Calories per gram = 544 Calories.

Step 3: Fat calculation.

·      Fat = 9 Calories per gram.

·      3177 TDEE x 0.2 – 0.35 = 635 – 1112 Calories of fat.

a.     Personal choice: 25% of TDEE of fat.

b.     3177 x 0.25 = 794 Calories.

c.     794 Calories ÷ 9 Calories per gram of fat = 88 grams of fat.

Step 4: Carbohydrate calculation.

·      Carbohydrate = 4 Calories per gram.

·      (3177 Calories) – (544 Calories + 794 Calories) = 1839 Calories.

·      1839 Calories ÷ 4 Calories per gram of carbohydrate = 460 grams of carbohydrate.

Step 5: Macronutrient Distribution

·      Protein – 136g

·      Carbohydrate – 460g

·      Fat – 88g

·      Total Calories: 3177

Many of the above calculations have been rounded to the nearest whole number for convenience. Once you’ve calculated the difference between where your average daily caloric intake is now versus where you “need to be” in the estimate, plan your additional Calories in 250 - 500 Calorie pockets and allow a few weeks for your body to acclimate to the new load. This will help ensure you stay as lean as possible. The opposite is also true for weight loss (subtract Calories slowly).

In an ideal world these numbers would align perfectly but this is rarely the case. Again, this is simply a guide to help navigate a weight gain / loss goal. In actuality you may reach your goal before or after actually hitting the estimated Calorie and macronutrient totals. If this is the case, as long as you proceed in a slow controlled fashion, you can stop once you’ve reached your goal weight. Another consideration is that the estimated TDEE for weight gain is already below what you require for your current weight maintenance. This highlights the fact that the ability to track your total daily Calorie intake / TDEE with reasonable accuracy and make informed increases or decreases in daily Calories is the true crux of your success.

Once you have become comfortable with the process, your macronutrients do not need to be this exact “style” of distribution. For example, the caloric “reservoir” style of carbohydrate calculation may also be redistributed into a more protein heavy diet depending on your personal preference. So long as your recommended minimum requirements have been met, there is a lot of individualization which may occur. When in doubt, seek professional guidance from a registered dietitian.

Best,

Eric