
The term macro-nutrients (macros) originates from the Greek word makros, meaning large. Macros are the nutrients you require daily in large amounts.
Macro-nutrients provide the body with energy (calories) and provide the building blocks of cellular growth, immune function, and overall repair. They are:
- Fat. 9 calories / gram;
- Protein. 4 calories / gram;
- Carbohydrate. 4 calories / gram.
Your body also requires micronutrients in smaller amounts, such as vitamins and minerals.
Fats
Of all the macro-nutrients, fats (and oils) provide the most energy (calories) per gram. Important for critical functions such as nutrient absorption (especially the fat soluble vitamins A, D, E & K), hormone production, temperature regulation and providing an alternative energy source (in fact, cardiac muscle cells derive up to 90% of their energy requirement from fatty acids).
Dietary fats are either saturated or unsaturated.
Saturated fats come mostly from animal sources. At the chemical level they are tightly packed and have no double bonds, hence the term saturated. These fats are generally solid at room temperature and tend to be shelf-stable for a longer period of time.
Unsaturated fats include those that are monounsaturated or polyunsaturated. Chemically, these fatty acids are loosely packed and have either a single (mono) or multiple (poly) double bonds. The important Omega-3 fatty acids belong in this group. Unsaturated fats are generally in liquid form even when refrigerated and have a shorter shelf life.
The recommended daily intake is between 20-35% of the total caloric intake, although many people find optimal function and performance at higher levels.
Good sources of healthy fat include fish, meats, avocado, nuts, butter, olive and coconut oils.
Proteins
Proteins are important for the body to be able to build and repair cells and tissue structures, produce enzymes and hormones as well as regulate your immune system. Protein requirements will vary depending on individual body weight and fitness levels.
Typical recommendations for protein intake is between 15-25% of the total caloric intake.
Good sources of protein include meat, fish, poultry, eggs, lentils and diary products.
Carbohydrates
Carbohydrates provide the body with fuel. They are broken down into sugars by the body and either provide immediate energy or are stored in the liver and muscles for later use in the form of glycogen.
Carbohydrates can either be complex or simple.
Simple carbohydrates (monosaccharides and disaccharides) are made up of either one or two sugar units and can be broken down fairly quickly in the body. Simply put, blood sugar levels typically rise quickly, then drop just as quick after the consumption of simple carbohydrates.
Complex carbohydrates (polysaccharides and oligosaccharides) are made up of long strings of sugar units that take longer to break down for use in the body. Due to these longer strings of sugars, complex carbohydrates take longer to be broken down and as such, generally have a lesser impact on blood glucose levels.
In addition to providing fuel to the body, complex carbohydrates, particularly fiber, can help the body to maintain healthy digestive function and a reduction in LDL cholesterol levels.
Although high, typical recommendations for carbohydrate intake is between 45-65% of the total caloric intake.
Good sources of carbohydrates include fruits, vegetables, tubers and grains.
How to actually count macro-nutrients
Use the following steps to effectively count macro-nutrients:
- Identify how many calories you want to eat each day.
- Identify the ratio of macro-nutrients that you want to consume. The current recommendations in Australia are as follows:
- Fat: 20-35%
- Protein: 15-25%
- Carbohydrate: 45-65%
- Multiply the total daily calories by the identified percentages.
- Divide the calorie amounts by the macro-nutrient calorie-per-gram number.
The Example
Our case athlete is following a 2,000 calorie diet using 25% fats, 25% protein and 50% carbohydrates.
Fat (9 calories / gram)
- 25% of 2,000 calories = 500 calories of fat per day
- total amount of fat per day = 500/9 = 56 grams
Protein (4 calories / gram)
- 25% of 2,000 calories = 500 calories of protein per day
- total amount of protein per day = 500/4 = 125 grams
Carbohydrates (4 calories / gram)
- 50% of 2,000 calories = 1,000 calories of carbohydrates per day
- total amount of carbohydrates per day = 1,000/4 = 250 grams
From these simple equations we can determine how many grams for each macro-nutrient our case athlete should be eating per day. With the above example to achieve the goal of 2,000 calories our case athlete would need to eat 56 grams of fat, 125 grams of protein and 250 grams of carbohydrates.
Let us look at one more case athlete. Still following an 2,000 calorie diet, but following a fairly standard ketogenic nutrition plan using 65% fats, 25% protein and 10% carbohydrates.
Fat (9 calories / gram)
- 65% of 2,000 calories = 1300 calories of fat per day
- total amount of fat per day = 1300/9 = 144 grams
Protein (4 calories / gram)
- 25% of 2,000 calories = 500 calories of protein per day
- total amount of protein per day = 500/4 = 125 grams
Carbohydrates (4 calories / gram)
- 10% of 2,000 calories = 200 calories of carbohydrates per day
- total amount of carbohydrates per day = 200/4 = 50 grams
For ketogenic case athlete to achieve the same goal of 2,000 calories they would need to eat 144 grams of fat, 125 grams of protein and 50 grams of carbohydrates.
Two different case athletes with different macro-nutrient breakdowns and achieving the same total caloric intake.
Final thoughts
Each macro-nutrient has important role in the body, essential to optimal health and performance. Understanding how to count these macros can produce a variety of health benefits, including the improvement in the overall quality of diet, smarter food choices and portion control, which when combined with a healthy exercise program can assist in reaching specific goals including improved body composition, lean muscle growth and / or effective weight loss.
When I track my calories I have found the CRONOMETER application to be a great tool for not only tracking macros, but have found that it also tracks more vitamins and minerals than any other application on the market.