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Introduction to Macronutrients

Nutrients are substances needed for growth, metabolism, and for other body functions. Macronutrients are the major (macro meaning large) nutrients that provide calories (energy) that are required by the body for optimal health.

Macronutrients also have specific roles in maintaining the body and contribute to the taste, texture, and appearance of foods, which helps to make the diet more varied and enjoyable. Macronutrients are essential what makes up the calories that you consume.

There are 3 broad classes of macronutrients:

1.  Proteins

2.  Carbohydrates

3.  Fats

While each of the macronutrients provides calories, the amount contributed by each varies.

Carbohydrates provide 4 calories per gram.

Protein provides 4 calories per gram.

Fat provides 9 calories per gram.


Proteins consist of strings of smaller units called amino acids, the “building blocks” of proteins.  Besides providing energy to the body, dietary protein is also required for growth: tissue repair, immune system function, hormone and enzyme production, and for lean muscle mass and tone maintenance.

There are 20 amino acids that are needed in the body. Our body can make 11 of them (called non-essential). However, 9 of them need to be obtained through the diet, naming them the “essential amino acids”.

A protein that comes from animal sources is called “complete proteins” because they contain all of the essential amino acids. Protein from plants, legumes, grains, nuts, seeds and vegetables are called “incomplete proteins” because they lack one or more essential amino acid(s).

Proteins are complex molecules and the body needs time to break them down. This is why they are a slower and longer-lasting source of energy than carbohydrates.   Protein is also the most satiating macronutrient, which provides the sense of fullness and satisfaction after a meal.

Foods that are a source of protein include:

  • Beef

  • Pork

  • Poultry

  • Fish

  • Eggs

  • Nuts

  • Seeds

Plant proteins: Plants, legumes, grains, nuts, seeds and vegetables provide low biological value proteins. However, combining proteins from different plant sources in the same meal often results in a mixture of higher biological value. Examples of such combinations are beans with rice, lentils with potatoes, etc.


There are two basic types of carbohydrates, depending on their size. Simple carbohydrates include various forms of sugar, such as glucose and fructose. Complex carbohydrates are more significant and consist of long strings of simple carbohydrates.

The human body uses carbohydrates in the form of glucose and it can convert both simple and complex carbohydrates into energy very quickly.  When carbohydrates are consumed in an excessive amount according to one’s output, the body will store it in the liver & muscle tissue as glycogen. This glycogen can be broken down & utilized later during physical activity and times of energy output. The body can hold thousands of calories as glycogen! However, if the stores are never used, it will be stored as fat.

Carbohydrates have two significant roles: they are the preferred energy source for the body and they are a source of calories. They are also involved in the construction of the body organs and nerve cells.

Dietary fiber, which is a carbohydrate, also helps keep the bowel functioning properly. Because they are smaller, simple carbohydrates can be broken down by the body more quickly and they are the fastest source of energy. Fruits, dairy products, honey, and maple syrup contain significant amounts of simple carbohydrates.

Complex carbohydrates also include starch, the primary energy reserve in root vegetables, grains, etc. Non-starch carbohydrates are the main components of dietary fiber.

The more simple sugar a food contains, the higher your blood sugar & insulin will rise. While carbohydrates provide an important role in body functioning, the amount and type should be tailored for one’s specific health needs, goals and overall activity levels.

Sources of dietary carbohydrates include:

  • Fruits, vegetables

  • Raw honey, pure maple syrup

  • Whole grains such as rice, quinoa
  • Root vegetables: yams, sweet potatoes, red potatoes, squashes
  • Legumes, lentils, beans

Dietary Fats

Besides being a source of energy, fat stores protect the internal organs of the body. Fats are also required for the production of hormones, supports cognitive function, helps heal & repair cells, and necessary for the formation of the cellular membrane. Fats are digested the slowest but the most energy-efficient form of food, since they have more than twice the calories per gram that provided by the two other macronutrients.

Fats that are in foods are combinations of 4 main types:

1. Saturated fats: They are solid at room temperature and are most often of animal origin. Examples are coconut oil, grass fed butter, ghee etc. These fats provide a concentrated source of energy in the diet and building blocks for cell membranes and a variety of hormones and hormone-like substances.

2. Monounsaturated fats: These are liquid at room temperature. Examples are olive oil, avocado oil, avocados, almonds etc. They appear to protect against heart disease, in that they reduce blood cholesterol levels.

3. Polyunsaturated fats: These fats  are also liquid at room temperature and can be further divided into the omega-6 and the omega-3 families. Polyunsaturated fats are thought to reduce the risk of coronary heart disease.

Omega 6 fats include: Almonds, pecans, seeds and also oils such as soybean, canola, vegetable, safflower etc.

Omega 3 fats include: salmon, herring, mackerel, walnuts, chia seeds, flaxseeds etc.

Unfortunately, most Americans over consume Omega-6 oils and are severely deficient in the Omega-3. Both are needed by the body, but in excess, Omega-6 promotes inflammation, while Omega-3s actually are anti-inflammatory.

The omega-3 forms are believed to have a positive impact on heart health and to play an important role in brain and eye function. It is important to avoid the processed Omega 6 oils completely while adding in the protective Omega 3s to your diet.

4. Trans fatty acids: They are produced by the partial hydrogenation of vegetable oils and present in hardened vegetable oils, most margarine, commercial baked goods, and many fried foods. An excess of these fats in the diet is thought to increase the risk of heart disease.

These are found in most all packaged and processed foods and usually used in fast foods & restaurants. These should be avoided completely! The words “hydrogenated” on the label is an indicator of these dangerous oils.

Sources of Dietary Fats include:

• Plant sources:
Coconut (oil, butter, milk, unsweetened shredded or flaked), avocado, olives, extra virgin olive oil, red palm oil, macadamia nut oil, nut butter, nuts such as walnuts, almonds, pecans, macadamia nuts, brazil nuts, seeds such as pumpkin, sesame, sunflower, flaxseed, hempseed, chia seed
• Animal Sources:
High quality fattier cuts of meats (grass fed red meat, pork, chicken thighs, ground chicken, ground turkey) fattier fish such as salmon, tuna, grass fed butter, whole eggs, whole fat organic dairy, hard cheeses like feta or goat cheese