What are macronutrients, anyway?

When there are so many diets in the media right now, it can be overwhelming to pick the right one for you when looking to change up your diet or lose a few pounds. Should you cut out bread? Are avocados the greatest food of all time? What should you be eating?

Well, it comes down to what the food is made of, which are called macronutrients. Macronutrients (macros for short) are what is found in food that provides the body with energy. There are three macronutrients: protein, carbohydrates (carbs) and fats. Protein is found in foods like eggs, meat, nuts, and other animal products. Carbs are found in foods like fruits, vegetables, dairy products, sugar, and grains. Fats are found in foods like avocados, nuts, and oils. Each macronutrient has a specific function in the body. Carbohydrates are the brain and body’s main source of energy, proteins help build muscle and repair damaged body tissues, and fats give our body cushion, support, and help the brain to function (2).

Each of these macronutrients have different amounts of calories in them, meaning they all give different amounts of energy. Protein and carbs gives us four calories for every gram of food that we eat, and fats give us nine calories for every gram we eat (1). What does this mean though? How much is a gram of food? Let’s take a bagel for example. One regular bagel has 48 grams of carbohydrate, which can be found on the nutrition label on the package (3). This means that one regular bagel has about 192 calories, because for every gram of carbohydrate there is four calories (3).

So, how much of each macronutrient is good to eat? People always preach about “eating healthy”, but what does that really mean? The Institute of Medicine suggests that 45-65% of our daily calories should come from carbohydrates, 10-35% of our daily calories from protein, and 20-35% of our daily calories from fats (2). This means that for an average diet, there should be 225-325 grams of carbohydrates, 50-175 grams of protein , and 100-175 grams of fat (2).

This is how people “count” their macronutrients. By keeping each macronutrient within these gram ranges, it’s easier to keep track of how much of each type of food is eaten throughout the day. Keeping track of the macronutrients makes it harder to overeat, because of the strict limitations on the allowed gram amount. For instance, back to the bagel example, eating seven regular bagels in one day would meet the daily recommendation for grams of carbohydrates (3). This makes it important to eat a variety of foods within each macronutrient category.

What is the right way to keep track? There are apps and websites available, or a journal or food diary could be kept. Just read food labels, figure out how much of each macronutrient is being consumed per meal or snack, then calculate how many grams of each macronutrients are eaten daily! Counting macronutrients can be useful for losing weight or to avoid overeating.

At the end of the day, eat real, whole foods like fruits and vegetables, whole grains, and dairy. Avoid eating processed foods or food full of sugar, and make sure to get plenty of exercise!

Resources

1. ODonoue, W. T., & Levensky, E.R. (2006) Promoting treatment adherence: A practical handbook for health care providers. London: SAGE.

2. Institute of Medicine. 2005. Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. Washington, DC: The National Academies Press. https://doi.org/10.17226/10490.

3. Nutrient Data Laboratory (U.S.), & Consumer and Food Economics Institute (U.S.). (1999). USDA nutrient database for standard reference. Riverdale, Md: USDA, Nutrient Data Laboratory, Agricultural Research Service.