Fitness Nutrition for Beginners: Macronutrients & Micronutrients
Ready to take control of your diet? Getting to know what’s on your plate is crucial for fueling your body correctly, and it all starts with a solid grasp of macronutrients and micronutrients. These aren’t just fancy terms—they’re the building blocks that keep us going and support long-term health.
In this post, I’ll walk you through what micronutrients and macronutrients are and how they connect to calories. Whether you’re a seasoned pro aiming to boost your performance or a newbie looking to balance your meals better, understanding nutrients is key to hitting your fitness goals.
What Are Nutrients?
Nutrients are essential for our bodies to grow and function properly. They form the backbone of a healthy diet and are crucial for things like energy production, growth, and tissue repair. Our bodies need two main types of nutrients: macronutrients and micronutrients, and we need them in different amounts. Let's dive into each one!
What Are Micronutrients?
Micronutrients, often called "micros," are essential compounds our bodies need in small amounts to perform important chemical reactions. You probably know them as vitamins and minerals.
Vitamins like A, C, D, E, and K, along with the B-complex vitamins, help with bone health, immune response, and energy production. Minerals such as calcium, potassium, iron, magnesium, and zinc are crucial for nerve transmission, fluid balance, and maintaining healthy bones and teeth.
While macronutrients provide energy in the form of calories, micronutrients don't have calories. However, they're essential for helping the body effectively use the energy provided by macros.
What Are Macronutrients?
As the name 'macro' hints, our bodies need macronutrients in larger amounts. They're our main energy source and are crucial for building our tissues and more. Macronutrients include carbs, proteins, and fats. Let's quickly check out what each one does.
Macronutrients: Protein
Proteins play a role in almost every part of cell life. They give cells their structure, form enzymes that aid metabolic reactions, help cells communicate, regulate acid-base and fluid balance, support our immune system, and more.
If you're into fitness, you'll love that protein aids in muscle growth and maintenance. It boosts performance and even gives your metabolism a slight kick. Plus, protein keeps you feeling full longer, making it easier to manage your calorie intake.
Macronutrients: Carbohydrates
Carbohydrates are mainly an energy source and your body's go-to fuel for high-intensity activities. They can be used right away or stored for later in your liver and muscles as glycogen.
Beyond energy, carbs are crucial for digestive health. Like protein, they help you feel fuller for longer.
While your body can make glucose from other stuff, it's not as efficient as getting it straight from carbs. So, if you're looking to improve body composition or boost athletic performance, making sure you get enough carbs is a smart move.
Macronutrients: Fats
Our bodies need fat to work properly. Contrary to what some might think, fats aren't always bad for us. Actually, they play a key role in keeping our immune system healthy, helping us absorb fat-soluble vitamins, and producing hormones like estrogen and testosterone.
Fat is also a great energy source, especially for long periods of low-intensity activities. It's our largest energy reserve because our bodies can store almost unlimited amounts of fat, unlike carbs, which are limited to what our muscles and liver can hold.
Where Do Calories Come In?
Let's talk about where calories come into play. Most foods are a mix of proteins, carbs, and fats, even if one macronutrient is more dominant. There are some exceptions, like oils, which are purely fat. But generally, foods combine different macronutrients. Take vegetables, for instance—they're mainly carbs but have small amounts of protein and fat.
Keep in mind that macronutrients provide energy, which means the calories in food come from its macronutrients. The total calorie count depends on how many grams of each macronutrient are in the food. This is because each macronutrient has a different calorie count per unit.
Here's a quick rundown of the calories in each macronutrient:
Protein contains 4 calories per gram
Carbohydrates contain 4 calories per gram
Fats contain 9 calories per gram
As you can see, fat-dense foods can pack more than twice the calories per gram compared to foods mainly made of protein or carbs with little to no fat. That's why small amounts of butter, oil, nuts, and peanut butter have way more calories than low-fat foods that are mostly carbs and protein.
Now that we know how many calories are in each gram of protein, carbohydrates, and fat, we can calculate a food's calorie content. Here's an example to show you how to do it. Suppose we have a food with the macronutrient breakdown on the label below, but the calorie count is missing, and we want to find out.
How to Calculate Calories from Macronutrients
To get started, we just need to multiply the grams of each macro by their specific calories per gram and then add them up. Here's how it breaks down:
2.6g of fat x 9 calories per gram = 23 calories
27g of carbs x 4 calories per gram = 108 calories
5.3g of protein x 4 calories per gram = 21 calories
Adding up the calories from each macronutrient gives us 152 calories. This would be the calories per serving you'd see on the label if it were visible. By the way, these numbers are for dry oats.
It's important to use total fat and total carbohydrates in these calculations. While fiber has fewer calories per gram than regular carbs, the exact number depends on the amounts of soluble and insoluble fiber and how your body processes it. To keep things simple, we'll just focus on the total carbohydrate content.
How to Calculate Macronutrient Ratios
Alright, so we know the calories. Now let's get a bit fancy and figure out the macronutrient ratios. We can do this by dividing the calories from each macronutrient by the total calories to calculate percentages.
Protein: 21 calories ÷ 152 calories = 0.14 x 100 = 14% protein
Carbs: 148 calories ÷ 232 calories = 0.71 x 100 = 71% carbs
Fat: 72 calories ÷ 232 calories = 0.15 x 100 = 15% fat
Just multiply each result by 100 to get the percentage. Double-check your math by making sure the results add up to 100%. As you can see, oats are about 70% carbs, with the rest of the calories split pretty evenly between protein and fat.
To summarize, because the calories per gram are different for protein and carbs compared to fats, make sure you convert grams to calories first when figuring out the macronutrient ratios. This way, you're comparing apples to apples.
Key Takeaways
Macronutrients are the three nutrients that give us calories: protein, carbs, and fat. They're crucial for energy, growth, overall health, and fitness. Protein and carbs each have 4 calories per gram, while fat has 9 calories per gram. By multiplying the grams of each macro by its calories per gram, we can calculate the calories each one adds to the total calories of a food.
