Understanding Macros: A Guide to Proteins, Carbs and Fats

Maintaining a healthy diet is crucial for overall wellbeing and optimal physical performance.

To achieve this, it's essential to understand the three primary macronutrients: proteins, carbohydrates and fats. These macronutrients provide the body with energy, support vital functions and play a significant role in body composition.

In this beginner's guide I'll delve into the details of each macronutrient and explain their functions, sources and recommended intake.


Proteins are often referred to as the building blocks of life. They are composed of amino acids and play a crucial role in the growth, repair and maintenance of body tissues, enzymes and hormones.

Here's what you need to know about proteins:

Proteins perform various functions, including the formation of structural components such as muscles, skin, hair and nails. They also play a critical role in immune function, transportation of molecules and cell signaling.

Sources: Excellent sources of proteins include lean meats (chicken, turkey, fish), dairy products (milk, yoghurt, cheese), eggs, legumes (beans, lentils, chickpeas) and plant-based proteins such as tofu and quinoa.

Recommended Intake: The Recommended Dietary Allowance (RDA) for protein is 0.8 grams per kilogram of body weight for the average sedentary adult.

However, athletes, active individuals and those undergoing muscle-building training may require higher protein intake to support muscle repair and growth.


Carbohydrates are the body's primary source of energy. They provide fuel for the brain, muscles and various other physiological functions. While carbs have often been misunderstood in recent years, it's essential to make informed choices.

Here's what you need to know about carbohydrates:

Carbohydrates are primarily responsible for providing energy to the body. They are broken down into glucose which is used by cells for various metabolic processes. Carbs also play a role in digestive health, brain function and athletic performance.

Sources: Carbohydrates can be classified into two types: simple and complex. Simple carbohydrates include sugars found in fruits, honey and processed foods. Complex carbohydrates are found in whole grains, vegetables, legumes and starchy foods like potatoes and corn.

Recommended Intake: The recommended carbohydrate intake varies based on individual needs and activity levels. Generally, carbohydrates should contribute to around 45-65% of total daily caloric intake.

However, it's important to prioritise complex carbohydrates and limit the intake of added sugars and highly processed carbs.


Fats are often misunderstood, but they play essential roles in the body. They are a concentrated energy source, aid in nutrient absorption and provide insulation and protection for vital organs.

Understanding the different types of fats is key to making healthy choices:

Fats are crucial for the absorption of fat-soluble vitamins (A, D, E and K) and support healthy brain function. They also provide insulation, protect organs and help maintain healthy skin and hair.

Sources: Fats can be categorised into four types: saturated fats (found in animal products and some tropical oils), unsaturated fats (found in plant-based oils, nuts and seeds), trans fats (found in processed and fried foods) and omega-3 fatty acids (found in fatty fish, flaxseeds and walnuts).

Recommended Intake: The American Heart Association recommends that saturated fat intake should be limited to less than 7 per cent of daily caloric intake. The British Nutrition Foundation advises less than 11 per cent.

Unsaturated fats, particularly monounsaturated and polyunsaturated fats, are considered healthier options and should replace saturated and trans fats in the diet. Including omega-3 fatty acids in the diet is also beneficial for heart health.

The total fat intake should generally be around 20-35% of daily caloric intake.

Related post: Why Fat Doesn't Make You Fat

Finding Balance and Individualising Macronutrient Intake

While understanding the functions, sources and recommended intake of macronutrients is important, it's equally crucial to find a balance that suits individual needs and goals.

Here are a few key considerations:

1. Energy Balance:
The total caloric intake should align with individual energy needs, which can vary based on factors like age, sex, activity level and goals (eg. weight loss, maintenance or muscle gain).

It's important to maintain a balance between the calories consumed and the energy expended.

2. Macronutrient Ratios: The optimal macronutrient ratios can differ depending on individual preferences and goals. For example, athletes or individuals engaged in intense physical training might benefit from a slightly higher protein intake to support muscle recovery and growth.

Experimenting with different ratios can help find the right balance.

3. Nutrient Timing: The timing of macronutrient consumption can impact energy levels, performance and recovery. For example, consuming carbohydrates before physical activity can provide readily available energy, while protein intake after exercise aids in muscle repair and synthesis.

Listening to the body's signals and adjusting nutrient timing accordingly can optimise results.

4. Quality Matters: While meeting macronutrient needs is important, the quality of the food sources shouldn't be overlooked.

Choosing whole, minimally processed foods ensures a higher intake of essential nutrients, fibre and phytochemicals, promoting overall health and wellbeing.

5. Individual Variations: Each person's nutritional requirements can vary, and it's essential to listen to your body's signals. Some individuals may thrive on lower carbohydrate diets, while others may perform better with a moderate carbohydrate intake.

Paying attention to how different macronutrients make you feel can help fine tune your dietary choices.


Understanding macronutrients is key to creating a well-balanced and nourishing diet. Proteins, carbohydrates and fats play distinct roles in the body, providing energy, supporting vital functions and contributing to overall health.

By including a variety of nutrient dense foods from each macronutrient group, individualising intake based on goals and needs, and focusing on high quality sources, you can optimise your nutrition and achieve your desired outcomes.

Remember, consulting with a registered dietitian or nutritionist can provide personalised guidance and support in determining the ideal macronutrient ratios for your specific needs.

With knowledge, experimentation and mindful choices, you can unlock the power of macronutrients to fuel your body, enhance performance and maintain optimal health.