Food Restriction
January 22, 2018
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What are Macronutrients?

What are Macronutrients?


Carbohydrates, protein, and fat make up the macronutrients.Carbohydrates contain 4 kcal/g, protein contains 4 kcal/g, and fat contains 9 kcal/g. When reading a nutrition label, you can calculate the total number of calories based on how many grams of carbohydrates, protein, and fat are in the food item you are looking at. For example, let’s look at this nutrition label of Jif peanut butter.

There are a total of 190 kcal in a serving size, but where does this number come from?


  1. 16 g fat x 9 kcal/g = 144 kcal
  2. 8 g carbohydrates x 4 kcal/g = 32 kcal
  3. 7 g protein x 4 kcal/g = 21 kcal
  4. 144 kcal + 32 kcal + 21 kcal = 189 kcal/serving


Macronutrient counting has been extremely successful for a wide variety of people because if you review and understand the above calculation, you’ll interpret macronutrient counting is really calorie counting. So then, why count your macros and not calories? There is no harm in counting calories, however macronutrient counting favors proportionality of those macronutrients to prevent nutritional deficiencies. It is quite possible when counting calories, you could eat 80% of your diet from fat. Counting macronutrients avoids this, by setting ratios to meet your nutrient goals. 


Carbohydrates are the body’s preferred fuel source composed of monosaccharides, disaccharides, and polysaccharides. Monosaccharides are the simplest form of carbohydrate and can not be further broken down. Examples include, glucose, fructose, galactose. Disaccharides are sugars composed of two monosaccharides, which can be broken down by hydrolysis. Examples include sucrose (glucose+fructose), lactose (glucose+galactose), and maltose (glucose+glucose). Polysaccharides are considered our complex carbohydrates, such as starch, cellulose, pectin, glycogen, and dextrin.


Examples of carbohydrates include whole grains (barley, buckwheat, farro, quinoa, millet, oats, rye, wheat), fruits, vegetables, bread, pastries, soda, pasta, and beans. Carbohydrates should contribute to 45-65% of our daily caloric intake, with the goal to make half your grains whole!



Protein plays a role in tissue synthesis, growth, and regulation of normal body processes. Active individuals require increased protein due to physical activity playing a role in muscle breakdown. There is ongoing research on the quantity of protein that active individuals need based on their output, however, for the healthy individual, the DRI (dietary reference intake) is 0.8g/kg BW to maintain normal body processes. This equates to 10-35% of total calories.


Amino acids are the building blocks of protein. There are 9 essential amino acids, which must be ingested from the diet. There are 11 non-essential amino acids that are naturally occuring in the body. A complete protein contains all the essential amino acids in sufficient quantities and ratios to maintain body tissue and promote tissue growth. An incomplete protein is deficient in one or more essential amino acids.


Examples of complete proteins include, eggs, beef, milk, fish, poultry, pork, and lamb. Incomplete proteins would include legumes, such as, beans, peas, and lentils, seeds, nuts, raw greens, avocado, and vegetables. Vegetarians benefit from combining incomplete proteins to produce a complementary effect that raises the protein quality compared to eating one incomplete protein alone.



Fat functions in energy, insulation, cellular production, brain development, and cell regeneration. Fat plays an essential role in absorbing the fat-soluble vitamins (A,D,E,K). Fat-soluble vitamins aid in skin, vision, enhance calcium absorption, act as antioxidants, and aid in blood clotting, respectively. Malabsorption of fat-soluble vitamins could lead to night blindness, rickets, osteomalacia, anemia, or hemorrhage.


20-35% of your diet should come from fats, which include nuts, fish, oils (olive, canola, safflower, avocado, corn, soybean, coconut), margarine, mayonnaise, avocados, nut butters, flax seeds, eggs, cream, and cheese.


By understanding what the function and sources of macronutrients are, you will be able to start creating a macro based diet that fits YOU. Although meal plans are convenient, macro counting gives you the freedom to make healthy decisions without feeling restricted.

Post by:

Abby King- Registered Dietician

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