A macro diet involves counting the intake of three macronutrients — proteins, fats, and carbohydrates. It divides daily calories into proportions, such as 10–35% proteins, 20–35% fats, and 45–65% carbs.

Although a macro diet primarily focuses on counting macronutrients, it also involves staying within a specific calorie range. A person will calculate their daily calorie needs and determine their macros accordingly.

Some people count their macros to reach weight loss goals, build muscle mass, and balance blood sugar levels. However, many people may find it time-consuming, socially restrictive, and confusing.

There can be risks associated with a macro diet if a person’s diet is too restrictive., such as deficiencies in certain vitamins and minerals.

Read more to learn about the three macronutrients, how counting macros works, and the risks and benefits of counting macros.

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Macros, or macronutrients, provide the body with energy. The three macronutrients –– protein, fat, and carbohydrate –– make up the foods people eat. Different foods contain different amounts of these macronutrients.

Protein, fat, and carbohydrates each contain a different amount of energy per gram (g). This article will refer to kilocalories (kcal) as simply calories.

Protein

The body needs proteins for the building and repair of tissues, cellular communication, enzymatic reactions, immune function, and more.

Examples of foods rich in protein include meat, fish, eggs, beans, tofu, and nuts.

There are approximately 4 calories in 1 g of protein. The Dietary Guidelines for Americans (DGA) recommends adults get 10-35% of their daily calories from protein. However, that amount may vary. It changes depending on a person’s age, body composition goals, muscle mass, and more.

Learn more about nutritious, high-protein foods.

Fat

Fat helps a person’s body store energy. It also protects the nerves, regulates hormones, aids in nutrient absorption, and maintains body temperature.

Examples of high fat foods include butter, oil, avocado, nuts, fatty fish, and meat.

There are 9 calories in 1 g of fat. According to the DGA, adults should get 20-35% of their daily calories from fat. Although the diet industry has historically vilified fat, it is essential for a healthy body.

Some fats may be a better choice than others. Saturated fat, which is solid at room temperature, should be consumed in moderation by most people. The American Heart Association (AHA) recommends no more than per day.

Unsaturated fat, such as monounsaturated and polyunsaturated fat, is liquid at room temperature. Nuts, seeds, avocados, and oily fish contain these fats. These are healthy fats, and diets that contain a good amount of these fats have associations with many health benefits.

Learn more about nutritious high-fat foods.

Carbohydrate

Carbohydrates, or carbs, are made up of sugar, starch, and fiber. They are the body’s main source of energy.

Examples of foods rich in carbs include potatoes, rice, pasta, fruit, beans, and oats.

Carbohydrates contain 4 calories per 1 g, and the DGA recommends adults get 45-65% of their daily calories from carbs.

People sometimes associate carbs with processed, less nutritious food items, such as cookies and white bread. However, many nutritious carbs are an essential basis of a balanced diet. Many of these foods are high in fiber and help keep a person full longer.

Additionally, the energy provided by carbs is essential for fueling the body and brain.

The amount of carbs a person needs varies. Some people thrive on lower carb diets, while others require a diet higher in carbs.

Learn more about nutritious carbohydrate-rich foods.

A macro diet involves counting macros instead of counting calories.

There is no one specific macro diet. Each person’s macronutrient needs are different, so no two macro diets will look the same. If a person wants to count macros, it is a good idea to consult a dietitian for advice on appropriate macro ratios.

People should follow several steps before starting a macro diet.

Determine caloric needs

There are a few ways a person can figure out their daily calorie needs.

First, they can use an online calculator, such as the popular If It Fits Your Macros (IIFYM) BMR calculator. Using information about a person’s body and lifestyle allows the app to estimate a person’s daily caloric needs.

Additionally, people can calculate their calories themselves using a formula. The Mifflin-St. Jeor equation is a popular choice:

  • Men: calories/day = 10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) + 5
  • Women: calories/day = 10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) – 161

Then, the person multiplies their result by an activity factor, which is a number that represents their daily activity level:

  • Sedentary: x 1.2 (little or no exercise; desk job)
  • Lightly active: x 1.375 (light exercise 1-3 days a week)
  • Moderately active: x 1.55 (moderate exercise 6-7 days a week)
  • Very active: x 1.725 (hard exercise every day or exercise twice a day)
  • Extra active: x 1.9 (hard exercise twice a day or more)

The final number is the person’s total daily energy expenditure (TDEE). This is the total number of calories they burn per day. People who want to either lose or gain weight can slightly increase or decrease their calories, although they should do so gradually.

Determine macronutrient ratio

Once a person has calculated their total daily calories, they can then determine their macronutrient ratio.

The DGA recommends the following ratio:

  • Proteins: 10–35% of total calories
  • Fats: 20–35% of total calories
  • Carbs: 45–65% of total calories

However, this ratio may not fit everyone’s goals. For example, endurance athletes may need more carbs, while a person with metabolic disease may thrive on a lower intake of carbs.

Track macros

After determining the macronutrient ratio, a person needs to track their food. Tracking macros means logging the foods consumed and paying attention to the macronutrients eaten.

There are a few ways to track macros.

For many people, the easiest way is to use a website or mobile app.

Others prefer to do the math by hand, although this takes more time. This typically involves a person calculating how many grams of each macronutrient they will consume per day by using the following formula:

(Total daily calories x macronutrient percentage) / calories per gram

So, if a person eating 2,000 calories per day wanted to know how many grams of carbs they should consume, and they aimed to get 50% of their daily intake from carbs, they would calculate:

(2,000 x 0.50) / 4 = 250g carbohydrate

Learn more about counting macros.

Some reasons why people choose to count macros include:

Before starting a macro diet, a person should consider the following.

Takes time

Tracking macros takes time. Unlike tracking calories, following a macro diet requires a person to pay close attention to the macronutrient ratio of everything they eat.

Lack of nutrient diversity

A macro diet could lead to a lack of nutrient diversity. It can be easy to overlook essential micronutrients because the diet focuses on protein, carbs, and fat.

A person following the macro diet does not need to consume nutritious food. The only guidelines are that the food falls within the acceptable macronutrient ranges. Consistently making poor dietary choices may lead to a variety of health problems.

Socially restrictive

Some people may find a macro diet socially restrictive. For example, a person may be less likely to go to dinner with friends because it is difficult to count the macros of food prepared by someone else.

Potential for disordered eating

Perhaps the most significant risk associated with counting macros is disordered eating.

In a 2017 study involving people who had received an eating disorder diagnosis, most participants said the My Fitness Pal tracking app contributed to their eating disorder.

Another 2017 study showed an association between calorie counting and regular health tracking with eating disorder attitudes and behaviors. This suggests that an intense focus on tracking health may even put people who do not have a history of eating disorders at risk for developing disordered eating behaviors.

It is advisable for anyone considering a macro diet to consult their doctor or dietitian for guidance.

Macronutrients — proteins, fats, and carbs — play essential roles in major bodily functions. Keeping track of a person’s macro intake may help some people reach their health and fitness goals.

However, for others, counting macros is time-consuming and restrictive. While there are benefits to counting macros, there are also risks. It is advisable to talk with a healthcare provider or a nutritionist before starting a macro diet.