The Three Macronutrients Your Body Needs Most

Grilled meats and vegetables
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Macronutrients are nutrients that the body uses in relatively large amounts and needs daily. There are three macronutrients: proteins, carbohydrates, and fats. The big three are separate from micronutrients, which the body requires in smaller amounts, such as vitamins and minerals. Macronutrients provide calories and the building blocks of growth, immune function and overall repair to the body and helps perform these and other normal daily functions.


The United States Department of Agriculture suggests 45 to 65% of our daily caloric intake come from carbohydrate. There are reasons why they suggest this. First, carbohydrate is known as the body's main source of fuel. Second, carbohydrate is the easiest way for the body to convert energy compared to fat and protein. Without carbohydrate and the soluble and insoluble fiber, it provides in addition to energy from glucose, intestinal health and waste elimination would be near impossible to maintain. Carbohydrate helps our bodies receive and release food. Some examples of foods high in carbohydrates are mainly found in starchy foods (like grain and potatoes), fruits, milk, and yogurt. Other foods like vegetables, beans, nuts, seeds and cottage cheese contain carbohydrates, but in lesser amounts.


In the absence of glucose or carbohydrate to convert into glucose, the body can process energy through a reverse conversion of energy using protein. Dietary protein is responsible for growth, muscle mass, hormone and enzyme production, tissue repair and immune function. Many Americans get more than enough protein from meats, poultry, fish, meat substitutes, cheese, milk, nuts, legumes, and in smaller quantities, starchy foods and vegetables. Complete proteins contain all of the essential amino acids and incomplete proteins are missing one or more of the individual essential amino acids. Incomplete proteins are found in plant-based foods, such as beans and rice. 


As much as 20-35% of your daily calories should come from fats. Dietary fat serves a very important function as the absence of it wouldn't allow for our bodies to get certain micronutrients. Fats also help us insulate our bodies and maintain our exercise sessions beyond our default energy glucose. Fat is also important in maintaining the texture and taste of food.

Striking a Balance

While daily recommendations look practical, finding a balanced mix of macronutrients at every meal is essential to maintaining your health. The large range of percentages recommended for each leaves room for anticipation, but finding the right ratio is less important than balance itself. That is, keeping each range within its boundaries, but ensuring you get each is the goal. And even when your ratios shift, be sure that you are consuming the right amount of calories in each category. Too much or too little will make you gain or lose weight. And although your ratios and caloric intake may change as you take on a low carb diet, it's essential that you continually keep your ratios in balance.

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Article Sources
  • Macronutrients: The Importance of Carbohydrate, Protein, and Fat. McKinley Health Center University of Illinois at Urbana-Champaign. 2014.