What are Macronutrients and their Importance in the Human Body?

You need macronutrients in large amounts to keep your body working. They are the crucial components of your structural and functional components. Whether you want to improve your health or want to achieve your dream figure, macronutrients are the key.

In this article, we have discussed the important concepts related to macronutrients which will give you a clear idea about their meaning, types, sources, and more.

The nutrients that our body requires in large proportions to function properly are known as macronutrients. They are also known as essential nutrients, as our body cannot produce the macronutrients in the required amounts.

When talking about the functions, each macronutrient has different functions in our body. At the time of digestion, they are broken down and are used in various bodily functions. Let’s look at each macronutrient one by one:

1. Carbohydrates

This is finally broken down into glucose or galactose. However, dietary fibre doesn't get digested along the gastrointestinal tract and a tiny bit of it gets fermented in the colon. The functions of carbohydrates are:

• Instant energy: Provides you with instant energy due to faster digestion of carbohydrates.
• Works as Energy Reserve: Excess carbohydrate is stored as energy for later use.
• Proper Bowel Movement: The dietary fibre facilitates proper bowel movement.
• Keeps Us Full: Carbohydrates and fibres keep you full for a more extended period of time.

2. Proteins

Proteins are building blocks of our body that get broken down into amino acids. To date, 20 amino acids have been discovered, out of which 9 are being supplemented by the foods we eat, and the rest are produced in our body. The following part enlists some of the functions of protein:

• Repair of Worn-out Tissue: New amino acids help in the repair of worn-out tissue and build muscles.
• Structural Component: Amino acids are responsible for the structure of cell membranes, skin, nails, and organs.
• Enzymes and Hormones: Amino acids are essential for the synthesis of enzymes and hormones.
• pH Level: Amino acids also maintain the pH level throughout our body.

3. Fats

Fats are finally broken down into simpler forms, known as fatty acids and glycerol. The main functions of fat include:

• Structural Component of Cell Membrane: The layers of the cell membrane are essentially phospholipid bilayers. Hence, lipids are a crucial part of our cell membranes.
• Shock absorber: Fats act as shock absorbers and protect the vital organs of our body.
• Energy Reserves: Fats can be stored as energy reserves which come in handy during long periods of starvation.
• Absorption of Fat-Soluble Vitamins: Fats also facilitate the transport and absorption of fat-soluble vitamins.

Some of the benefits of macronutrients are:

• Improve Immunity: Proper intake of macronutrients help us to fight several infections and chronic illness by boosting our immune system.
• Provides Energy: Macronutrients are majorly responsible for the energy provision of our body.
• Builds Up Athletes: An adequate amount of macronutrient consumption helps to build up the body of athletes and enhance their performance as well.

A macro diet comprises three components: carbohydrates, proteins, and fats. After working out the daily needs, the calories must be divided into proportions. Also, a macro diet focuses on counting the macronutrients rather than counting calories.

Some people might be on a macro diet for weight loss and build muscle mass, whereas others may find it completely nonsensical, time-consuming, and socially restrictive. On top of that, if a diet is very restrictive, the person may suffer from vitamin and mineral deficiency.

There are three things to keep in mind while counting your macros. Let’s look at them one by one:

• Make out the caloric needs: There are two ways to determine caloric needs. The first one is by using online calculators, while the second way is to calculate them manually. Let’s look at the formula:
  • For Men: 10*weight in kgs + 6.25*height in cms - 5*age in years + 5.
  • For Women: 10*weight in kgs + 6.25*height in cms - 5*age in years - 161.

After this, you need to multiply it by an activity factor to calculate the total daily energy expenditure. This is different for people engaged in different types of work:

• Make out the ratio for macronutrients: After calculating your daily caloric needs, focus on the macronutrient ratio. As per the American Dietary Guidelines, we have the following:
  • Carbohydrates: 45% to 65% of total caloric needs. 
  • Proteins: 10% to 35% of total caloric needs. 
  • Fats: 20% to 35% of total caloric needs.

However, this ratio varies from person to person.

• Track your macronutrients: This step requires keeping track of the foods that you consume throughout the day and focusing on the macronutrients you are taking in. The formula for this is:

(Daily Caloric Needs*Macronutrient Percentage)/ Calories present in the food per gram.

For example: In case a person consumes 3,000 calories per day and take 60% of the daily intake from carbohydrates, the grams of carbohydrate consumed will be:

(3,000 x 0.60) / 4 = 450g carbohydrate

It is very important to eat all your foods in the correct proportions so as to get an adequate amount of each macronutrient. The following part enlists the sources of each of the macronutrients.

• Carbohydrates:
  • Vegetables: Include corn, potatoes, peas, and other starch-containing vegetables.
  • Dairy Products: Include curd, milk, and milk chocolates.
  • Whole Grains: Include farro, barley, brown rice, etc.
  • Fruits: You can eat any fruit based on your liking.
  • Beans and Legumes: Includes lentils, black beans, and chickpeas.
• Proteins:
  • Seafood: Includes fish such as shrimp, salmon, and cod.
  • Dairy Products: Includes curd, milk, and milk products.  
  • Soy Products: Includes tofu, tempeh and edamame.
  • Nuts and Seeds: Includes walnuts, almonds, and edible seeds of all kinds.
  • Red Meat: Includes pork, lamb, beef and mutton.
  • Poultry: Includes turkey and chicken.
  • Eggs: Only egg whites, avoiding the egg yolk.
  • Beans and Legumes: Includes lentils, chickpeas, and black beans.
• Fats:
  • Avocados: Includes freshly plucked avocados along with avocado oil.
  • Coconut: Includes coconut in all forms such as fresh, dried, or in oil form.
  • Fatty Fish: Includes herring and salmon.
  • Nuts and Seeds: Includes all kinds of edible seeds along with edible nuts.
  • Dairy Products: Includes all milk products such as cheese and fat-laden yoghurt.