Macronutrients: a guide to your fav P/F/C trio
You’ve probably seen countless amounts of content about how to calculate your macros, macro-based diets, etc, but rarely does it get to the most important question: what IS a macronutrient?
Macronutrients, aka proteins, carbohydrates, and fats, are the crucial blocks used to provide energy needed for daily activities and essential physiological functions. To leave it at that, however, neglects important nuances on how macronutrients work. We’re getting into the nitty gritty of macros — from amino acids to polysaccharides, get ready for some geeky reading.
What are macronutrients?
Macronutrients are the three main categories of nutrients required by the body in relatively large amounts: protein, carbohydrates, and fats. Each macronutrient plays a unique and important role in supporting various bodily functions, ensuring optimal performance and well-being. These macronutrients are the building blocks that fuel and sustain our bodies.
Macronutrients and calories
Calories are a unit of measurement for energy, and macronutrients are the components of food that provide this energy. Each macronutrient contributes a certain number of calories per gram:
Proteins: 4 calories per gram
Carbohydrates: 4 calories per gram
Fats: 9 calories per gram
Whenever you chow down, the macronutrients present in that food contribute to the total caloric content of the meal. The energy derived from macronutrients is used by the body for various functions, including maintaining bodily functions at rest (basal metabolic rate), supporting physical activity, and facilitating the digestion and absorption of nutrients.
Proteins
Protein is a critical macronutrient that serves as the foundation for the body's structure and function. It’s composed of amino acids, which are essential for muscle development, repair, and overall cellular health. Adequate protein intake is necessary for the proper functioning of organs, immune system support, and the production of enzymes and hormones.
Animal-based proteins
Sources of animal-based protein include meat, poultry, fish, eggs, and dairy products. These foods are rich in complete proteins, meaning they contain all the essential amino acids required by the body. Incorporating a variety of animal-based proteins into your diet supports a well-rounded amino acid profile.
Plant-based proteins
For those following a vegetarian or vegan lifestyle, plant-based protein sources are abundantly available. Legumes, beans, nuts, seeds, and soy products are excellent alternatives.
Although plant-based proteins may lack some amino acids found in animal-based sources, combining different plant-based foods can provide a complete set of essential amino acids. Rice and beans, for example, is one of the most common combos that provides all nine essential amino acids.
Carbohydrates
Carbohydrates are a class of macronutrients formed from carbon, hydrogen, and oxygen that serve as a primary source of energy for your body. Carbohydrates come in various forms, and they play a crucial role in fueling physiological processes and supporting overall health.
When consumed, carbs are broken down into glucose (a type of sugar), which is then used by cells for energy production. The digestion and processing of carbohydrates involve a series of complex biochemical reactions that break down these macronutrients into simpler forms — glucose, fructose, galactose — for absorption into the bloodstream and utilization by the body.
Your body regulates the storage and uptake glucose levels to provide you with energy as needed. Many athletes and fitness enthusiasts take advantage of this process to optimally fuel their training — runners and other endurance athletes, for example, are known for eating carb-heavy meals the evening before a race. During a run or race, you’ll often see them sipping on sugary drinks or snacking on candy and carb gels. This approach helps support energy levels and performance as it keeps glucose at the ready and the dreaded bonk away.
Carbohydrates are classified into two main types: simple carbohydrates and complex carbohydrates.
Simple Carbohydrates
Simple carbohydrates, also known as simple sugars, are a type of carbohydrate composed of either one (monosaccharides) or two sugar molecules (disaccharides). Simple carbohydrates are found naturally in some foods, such as fruits and milk, as well as in processed and refined sugars.
Examples of monosaccharides include:
Glucose: Found in fruits and vegetables, and a primary source of energy for the body
Fructose: Naturally occurring in fruits and honey.
Galactose: Found in milk and dairy products
Examples of disaccharides include:
Sucrose: Composed of glucose and fructose; found in table sugar, sugarcane, and sugar beets
Lactose: Composed of glucose and galactose; found in milk and dairy products
Maltose: Composed of two glucose units; found in malted foods and some beverages
Due to their simple structure, these carbohydrates are quickly digested, providing a rapid but short-lived source of energy. The rapid digestion of simple carbohydrates can lead to a quick increase in blood sugar levels, which is important for individuals with diabetes or those aiming to manage their blood sugar. Simple carbohydrates, often in the form of sports gels and drinks, are sometimes consumed by athletes for quick energy during intense physical activity.
Complex Carbohydrates
Complex carbohydrates, also known as polysaccharides, are a type of carbohydrate composed of long chains of sugar molecules, which you may know as starch and fiber. These complex chains can be branched or unbranched, and they may contain hundreds to thousands of sugar units that require more time and effort to break down during digestion. The result is a slow and sustained release of glucose into the bloodstream, providing longer-lasting energy but less immediate access than simple sugars.
Often containing important vitamins, and minerals, complex carbs support satiety, your diet’s nutritional profile, and healthy blood sugar levels. Whole plant foods are rich sources of complex carbohydrates. Examples include:
Whole grains: Brown rice, quinoa, oats, barley, and whole wheat.
Legumes: Beans, lentils, and peas.
Vegetables: Sweet potatoes, broccoli, carrots, and leafy greens.
Fruits: Fruits provide fiber and various nutrients, contributing to their classification as complex carbohydrates.
Fiber
Dietary fiber is a type of carbohydrate that the body cannot digest or absorb. Unlike other carbohydrates that are broken down into sugars during digestion, fibrous carbohydrates pass through the digestive system relatively intact. Instead of providing calories or energy, dietary fiber offers various health benefits cholesterol management and blood sugar regulation. It also helps keep your digestive system happy by aiding food movement… in other words, fiber helps you poop.
Fats
Fats, also known lipids, are a macronutrient that have faced particular demonization in diet culture. Contrary to popular misconceptions, fats don’t directly contribute to weight gain/loss. Rather, fats are composed of fatty acids that can offer an abundance of nutrients crucial for various physiological processes including absorbing vitamins, protecting organs, and supporting brain function.
Fats are a concentrated source of energy, providing more than twice the calories per gram compared to carbohydrates and proteins. They serve as a long-term energy storage mechanism in the body.
There are three main types of fats: saturated fats, unsaturated fats, and trans fats.
Saturated Fats
Saturated fats are a type of dietary fat in which the fatty acid chains lack double bonds between the individual carbon atoms. These fats are typically solid at room temperature and are commonly found in the following sources:
Animal products: Saturated fats are prevalent in animal-based foods such as red meat, poultry with skin, whole-fat dairy products (whole milk, cheese, butter), and fatty cuts of meat.
Certain plant oils: While most plant oils are unsaturated, some tropical oils like coconut oil and palm oil contain high amounts of saturated fats.
High intake of saturated fats has been associated with an increased risk of cardiovascular diseases. Consuming too much saturated fat may contribute to elevated levels of LDL cholesterol, often referred to as "bad" cholesterol as it’s a risk factor for heart disease.
That doesn’t mean that saturated fats are bad — the relationship between dietary saturated fats and heart health is complex and may depend on various factors, including overall diet and individual health status. There’s ongoing debate around the health benefits of saturated fats, but research so far suggests that, besides being a great source of long-term energy, saturated fats can aid hormonal regulation and cognitive health.
Unsaturated Fats
Unsaturated fats, found in olive oil, avocados, and nuts, are a type of dietary fat characterized by the presence of one or more double bonds in the fatty acid chain. These fats remain in a liquid state at room temperature and are known to carry certain health benefits when compared to saturated fats.
Unsaturated fats are classified into two main types: monounsaturated fats and polyunsaturated fats. Each type can help improve blood lipid profiles by reducing levels of LDL cholesterol while maintaining or increasing HDL ("good") cholesterol, potentially reducing the risk of heart disease.
Monounsaturated fats have one double bond in the fatty acid chain. Foods rich in monounsaturated fats include:
Olive oil
Avocados
Nuts (e.g., almonds, peanuts, cashews)
Seeds (e.g., sunflower seeds, pumpkin seeds)
Canola oil
Polyunsaturated fats have multiple double bonds in the fatty acid chain. There are two main types of polyunsaturated fats: omega-3 fatty acids and omega-6 fatty acids. Omega-3 fatty acids, a type of polyunsaturated fat, are crucial for brain health and cognitive function and exhibit anti-inflammatory properties. Foods rich in polyunsaturated fats include:
Omega-3 fatty acids:
Fatty fish (e.g., salmon, mackerel, trout)
Flaxseeds and flaxseed oil
Walnuts
Chia seeds
Hemp seeds
Omega-6 fatty acids:
Vegetable oils (e.g., soybean oil, corn oil, safflower oil)
Nuts and seeds
Sunflower oil
Evening primrose oil
Trans Fats
Trans fats, or trans-unsaturated fatty acids, are a type of dietary fat that is formed through a process called hydrogenation. Hydrogenation involves adding hydrogen atoms to liquid vegetable oils, turning them into solid fats. Trans fats can also occur naturally in small amounts in some animal products.
High consumption of trans fats has been associated with an increased risk of cardiovascular diseases as they raise levels of LDL cholesterol and lower levels of HDL cholesterol, contributing to an unfavorable lipid profile. Health organizations, including the World Health Organization (WHO) and the U.S. Food and Drug Administration (FDA), recommend minimizing the intake of trans fats for heart health. Many countries have implemented regulations to limit or ban the use of artificial trans fats in food products.
FAQs about macronutrients
How can I ensure I get enough protein in a vegetarian or vegan diet?
Incorporate a variety of plant-based protein sources. Consider combining complementary proteins to ensure you get all essential amino acids.
What role do carbohydrates play in a balanced diet?
Carbohydrates are the body's primary source of energy, providing fuel for daily activities and supporting various physiological processes.
Why is it important to balance macronutrient intake?
A balanced intake of macronutrients ensures that the body receives the necessary nutrients for optimal functioning, supporting overall health and well-being.
Can I lose weight by eliminating fats from my diet?
While reducing unhealthy fats is advisable, completely eliminating fats from your diet is not recommended as they’re crucial for many physiological functions.
