These days, it’s not uncommon to know someone who is working hard to lose weight or eat healthier. The presence of fad diets, cleanses, supplements, and celebrity-sponsored fitness programs have made weight loss a popular goal for many. Despite this, most people aren’t aware of one of the most important elements of a healthy diet: macronutrients. Knowing what macronutrients are, and more importantly how to monitor them, is a surefire way to build a successful weight loss and healthy eating plan.

What Are Macronutrients?

Macronutrients are the essential elements that make up a significant portion of the food people eat. While this includes necessary vitamins and minerals, the term refers to carbohydrates, proteins, and fats. Everyone requires these three nutrients to survive, but most people get either too few or too many of one nutrient. American cuisine is known for being high-fat and high-carb, and though these are important parts of a diet, the amount most Americans consume is far greater than the recommended level. When these excess carbs and fats are not used directly for energy, they are stored as fat in the body and can result in a multitude of health problems, including weight gain.

Calculating BMR

For the average person, the ratio of daily macronutrient intake is roughly 45% carbohydrates, 35% protein, and 20% fats. How many grams of carbs, fats, and proteins this equals varies based on a variety of factors such as gender, age, and activity level. Therefore, to know how many macronutrients you need, you must be aware of your basal metabolic rate, or BMR, which is how many calories you burn while performing routine daily activities (i.e., breathing, sleeping). Once you calculate this figure, you can use it to determine how many calories you need from each macronutrient category.

There are many ways to determine your BMR, including handy online calculators, all of which are based on the Mifflin-St. Jeor equation. It’s important to note that the BMR equation differs between males and females, but uses the same information (height, weight, and age). These formulas are:

Females: 10 x weight in kg + 6.25 x height in cm – 5 x age – 161

Males: 10 x weight in kg + 6.25 x height in cm – 5 x age – 5

A lot is going on here, which is why many people opt for an easy calculator that takes in their information. However, it’s relatively straightforward. For example, imagine Sarah, a 27-year-old female, weighs 65 kg and is 168 cm tall. The formula would look like this:

(10 x 65 = 650) + (6.25 x 168 = 1,050) – (5 x 27 = 135) – 161.

This equals out to (650 + 1,050 – 135 – 161) or 1,404 calories. The final step in calculating Sarah’s BMR is to multiply this number by a figure called the activity factor (AF), which is based on the amount of energy a person expands on a typical day. The list of AFs is:

• Sedentary individuals: 1.2
• People who work out one to three times a week: 1.375
• Individuals working out three to five times a week: 1.55
• Those exercising six to seven times a week: 1.725
• Athletes or people with physically demanding jobs: 1.9

If Sarah works out five days a week, her original figure (1,404) gets multiplied by the AF for people who work out five days a week (1.55), which would equal roughly 2,176 calories. The result is the number of calories Sarah burns on an average day.

Using BMR to Find Macronutrients

There are two ways someone can use their BMR to see how many macronutrients they need. The first strategy is for people who are looking to maintain their weight and neither gain nor lose pounds. These individuals would find their macronutrient percentages based on their BMR. Doing so requires knowing how many calories there are in each gram of a macronutrient. One gram of protein or carbs contains roughly 4 calories whereas 1 g of fat is 9 calories. For example, Sarah needs approximately 244 g of carbs each day. She finds this by calculating 45% of her BMR (2,176 x .45 = 979), which is the recommended daily percentage of carbohydrates, and dividing this number by 4 since there are 4 calories in each gram of carbohydrates (979 / 4 = 244). This same method is used to find that Sarah needs 190 g protein and 48 g fat each day.

The second method of calculating macronutrients applies to people who are looking to change their weight by either gaining or losing pounds. In this case, that person would use their desired weight to figure out how many calories they should eat. If Sarah, for instance, decided she wanted to lose 8 pounds in the next eight weeks, she would calculate her caloric intake based on the knowledge that 1 lb of fat loss requires burning 3,500 calories. That means if Sarah eats 500 fewer calories per week than her BMR (2,176 – 500 = 1,676), she will lose 1 lb per week for eight weeks and end up losing 8 lbs. To calculate her new macronutrients, she would substitute this new calorie level (1,676) and perform the same calculations. For example, Sarah’s new carbohydrate requirement is 188 g because (1,676 x .45 / 4 = 188).

These calculations may seem like a lot of work, but often people struggle to lose weight or achieve a healthy diet because they neglect to monitor their macronutrient intake. Fortunately, several websites calculate BMR, which makes finding macronutrient levels much simpler. Keep in mind that while these formulas can be useful, they are generalizations and apply to the average person. Due to variations in activity level or health issues, some people require more or less than the recommended macronutrient levels provided by the USDA. These individuals should seek advice from a dietician or primary physician. For most people, however, these formulas offer an accurate representation of what the human body needs for optimal health and performance.