The Role of Macros for Weight Loss

Carbohydrates, protein, and fats are macronutrients—nutrients you need in large quantities because they are essential for the body's function. They provide energy and structural components for cell growth, development, and repair. Most foods contain all three macronutrients in varying amounts.

Various weight loss eating plans require you to follow different distributions of macronutrients. A ketogenic diet limits carbohydrate intake to 50 grams (10% of total calories for someone consuming 2,000 kilocalories a day).

The Dietary Guidelines for Americans recommends that 45-65% of calories come from carbohydrates.

How Macros Affect Weight Loss

Eating plans emphasize macronutrient distributions because they can affect how you lose weight, such as whether it is healthy for you to restrict carbohydrates, whether you are eating enough protein to avoid losing muscle instead of fat, whether the foods you eat provide satiety, and more.

You need all three macronutrients—carbohydrates, protein, and fat—to support weight loss while maintaining your health.

Protein

Proteins contain amino acids. Each gram of protein provides 4 kilocalories, but your body does not use protein as a primary energy source. Protein is primarily a nutrient that builds muscle, prevents muscle loss, supports the immune system, and produces hormones, enzymes, and neurotransmitters.

Sufficient protein intake is critical for losing fat while maintaining muscle mass. Losing muscle mass can cause a decrease in resting energy expenditure over the long term, making it harder to lose and maintain weight.

Although optimal protein intake will vary by person, guidelines recommend at least 0.8 grams per kilogram of body weight. A person who weighs 70 kilograms needs 56 grams of protein to meet the minimal protein requirement.

Inadequate protein intake can cause muscle loss, decreased bone mass, impaired hormone production, anemia, and skin issues.

Carbohydrates

Carbohydrates are the body's primary energy source. They provide 4 kilocalories per gram. Fiber, a carbohydrate found mainly in complex carbohydrates, is important for gut and immune function and helps maintain metabolic and heart health.

If you don't get enough carbohydrates, your body will still produce energy from fats and protein. Your body's use of protein for energy can cause you to lose muscle mass.

Restricting carbohydrate intake can be taxing on your body, and many people find it difficult to maintain energy and motivation. It also limits the intake of essential nutrients. On the other hand, excess carbohydrate intake can cause you to exceed your calorie intake.

People with prediabetes and diabetes can develop serious health problems when they eat too few carbohydrates. Limited fiber intake—due to decreased carbohydrate intake—can also contribute to higher cholesterol and blood glucose levels and negatively impact your gut health.

Fats

Fats provide the most energy: 9 kilocalories per gram. They play a role in regulating body temperature, producing sex hormones, contributing to cell structures, and helping absorb fat-soluble vitamins (vitamins A, D, E, and K).

While your body needs fat, a diet mostly consisting of unsaturated fats over saturated fats is recommended. Unsaturated fats include olive oil, nuts, seeds, fatty fish, and avocados. Saturated fats naturally exist in animal-based foods and are present in higher levels in fast and processed foods.

While unsaturated fats are associated with health benefits, saturated fats can increase cholesterol levels and the risk of heart disease.

What's the Best Macro Ratio for Weight Loss?

There is no universal best macro ratio for weight loss. Although there are guidelines for carbohydrate, protein, and fat ratios, actual needs differ for every person. Research has not identified one single dietary pattern that leads to weight loss for everyone.

The difference between macronutrients can significantly differ by diet. One study found that among the most popular diets, carbohydrate content ranges from 40-60%, protein from 10-30%, and fat from 20-55%.

How To Calculate Your Macros

If you want to count your macronutrients, you can do so with some calculations, food journaling, or help from phone applications.

Calculate Your Calorie Needs

Calculate how many calories you'll need to lose weight. There are various methods for doing this.

One easy way is to use a body weight planner. You'll enter your weight, height, age, gender, physical activity levels, how much weight you want to lose in how much time, and whether you will increase your activity, among other factors. The calculator will then tell you how many calories you should consume to reach your goal.

Determine Macronutrients Distribution

Different diets come with varying distributions of macronutrients. The 2020-2025 Dietary Guidelines for Americans recommends adults get 45-65% of calories from carbohydrates, 10-35% from protein, and 20-35% from fat.

Calculate Your Macro Intake

Now that you know your calorie needs, let's say you need 1800 calories to lose weight and will use the macronutrient ratios given above. Your macronutrient targets would be approximately 202.5-292.5 grams of carbohydrates, 45.7-157.5 grams of protein, and 40-70 grams of fat.

Track Macro Intake

There are many tracking apps available that allow you to set your macro goals and calculate macros when you enter meal details. Some apps can even do this by analyzing pictures of your meals.

Macro Sources To Support Weight Loss

You need to learn which foods contain particular macronutrients to target your macro distribution. Here are sources of macronutrients:

• Proteins: Beef, poultry, fish, seafood, eggs, dairy products, and plant-based protein sources such as beans, lentils, nuts, seeds, and soy products
• Carbohydrates: Simple carbohydrates like sugars, fruits, grains, and starchy vegetables and complex carbohydrates like whole grains, beans, legumes, and vegetables
• Fats: Vegetable oils, nuts, seeds, avocados, and animal fats found in meat, poultry, fish, and dairy products

Other Nutrition Factors To Consider

If you want to lose weight or are already following a weight-loss diet, here are a few things that are helpful to know:

• Optimum nutrition is different for everybody: Your nutritional needs are unique and influenced by health, genetics, gender, age, body weight, body composition, physical activity level, and lifestyle. It's essential to make personalized nutritional choices.
• Weight loss is meant to be slow: Losing 1-2 pounds (0.5-1 kilograms) per week is recommended. You may lose a bit more at first, but with time, you'll likely lose a lesser amount until you settle the target weight. Fast weight loss can cause loss of muscle mass, gallstone formation, gastrointestinal discomfort, and tiredness.
• Consult a professional: The process of losing weight is not the same for everybody. Some can lose weight by simply lowering their calorie intake, while others may need a more tailored nutrition plan that meets their nutritional needs and requirements.
• Tools can help: MyPlate Plan can calculate your daily calorie needs and show recommended intakes for foods and food groups based on those calories. The MyPlate app can help you track and set goals related to food and food groups.
• Get active: Moving your body can contribute to weight loss and overall health. The World Health Organization (WHO) recommends at least 150 minutes of aerobic activity (such as walking, running, swimming, or dancing) and two days a week of strength training for adults.
• Read Nutritional Fact labels: Packaged foods display nutrition fact labels. Reading these labels can help you choose more nutritious foods while shopping.

A Quick Review

You need all three macronutrients for weight loss while maintaining health. The optimal distribution of macronutrients varies from person to person.

If you don't have guidance from a healthcare provider, you can follow the recommended macronutrient distribution by the Dietary Guidelines for Americans for a healthy and balanced diet while maintaining a 300-500 calorie deficit for slow, long-term weight loss.