Updated: Nov 16
Having a basic understanding of nutrition will help you create a diet that is enjoyable to you while also helping you reach your fitness and body composition goals.
In this post:
A calorie is simply the amount of energy required to raise one gram of water by 1 degree Celsius. When we talk about food, we actually use kilocalories, which means the amount of energy required to raise 1000g (a kilo) by 1 degree Celsius.
For the sake of simplicity, we can consider a calorie to be a unit of energy.
Why does your body need calories?
Our body needs a molecule called ATP (Adenosine Tri-Phosphate) to produce muscular contractions.
These contractions are occurring constantly, with or without our knowledge. Your heart, intestines and other organs all have their own muscular contractions, even without us thinking about it.
We only have a limited amount of ATP in our body and we are constantly making more of it and breaking it down. It’s during this process that the energy from food turns into the energy being used up for life.
Calories are not all equal
Nutrients are vitamins and minerals, molecules that help your body function at its best. A lack of these nutrients, (nutrient deficiency) can lead to poor performance and even illness.
Nutrient density is the amount of nutrient that comes with each calorie. Think of it like a ratio.
For example, a serving of blueberries has many more nutrients for a given number of calories than a milkshake does.
Foods that are high in nutrients usually come from natural and unprocessed sources.
To be sure about how natural a food is, you can ask yourself three questions:
Can I pick it from a plant or tree
hunt it or fish it
dig it from the ground
If the answer is no to all three, that food has been processed in one way or another. As a general rule, the more food is processed, the fewer nutrients it has.
If we take bread or pizza for example, you can still have delicious, minimally processed pizzas and bread if all ingredients are natural. Or you can have more processed pizzas and breads with preservatives, white flour, and other processing techniques.
Beginner nutrition: Macronutrients
Macronutrients (macros) are nutrients that contain calories in them. They include fats, protein, carbohydrates (carbs) and alcohol.
When you eat these nutrients, you absorb calories in your body. Each macro contains a different amounts of calories:
One gram of fat contains 9 calories
One gram of protein contains 4 calories
One gram of carbohydrate contains 4 calories
One gram of alcohol contains 7 calories
Once they go through your stomach and get digested, proteins are broken down into amino acids. You may have heard this term before if you take BCAA supplements (Branch Chain Amino Acid).
Amino acids are the molecules that make up protein. Think of them as the building blocks of your body. They are used to make muscles, collagen (all your tendons and ligaments and other stuff like that), antibodies, enzymes and much more.
When you digest a protein molecule, you form a bunch of these amino acids which are in turn rearranged into different forms of tissue, according to your body’s needs.
It is recommended that you consume between 1.5g to 2g of protein per kilogram of body weight. I weigh 81 kg so I need to eat 81 x 2 = 162g of protein each day.
When a carbohydrate molecule gets digested, whether it’s a healthy or unhealthy carb, the end molecule is the same, it turns into glucose. So whether you eat ice cream or a fruit, you end up with molecules of glucose in your body.
Once glucose is digested, it goes into the bloodstream and looks for a purpose. Your body loves to use glucose to create ATP, so that’s what glucose molecules are looking for.
If there is no work for the glucose molecule, your body wants to keep it for future use, and it converts the glucose into fat molecules that are stored in your fat cells.
Different carbs affect blood glucose differently. I’m sure you’ve heard the terms complex carbs and simple sugar before.
Complex carbs are more natural than simple sugars and are overall, healthier for your body. Simple sugars are processed carbs that tend to have a lot fewer micro nutrients.
Simple sugars are not “bad” per say, it just depends on your goals.
When I am about to workout I eat simple sugars for the reasons mentioned in the table: they don't make me feel full, I get energy from these sugars and they get digested quickly, so I can use up the energy during my workout.
Also, eating a well balanced meal including protein and fats helps to reduce the blood sugar spike from the simple sugars.
When I am about to go to bed, I prefer eating complex carbs because it won’t spike my blood sugar, it brings in more nutrients, and makes me feel more full, so I eat fewer of them.
We will discuss later in this article what is the recommended amount of carbs you need to eat each day.
Your body needs fat for cell repair and function, to absorb vitamins A, D, and E, to regulate cell signalling, to help with hormone function and many other key functions. As with carbs, the source of those fats are important because more natural fats are going to be better for us than processed fats.
Fats can be organized into four distinct groups:
Monounsaturated fats: these are good for us, they are found in olive oil, most nuts and seeds, and avocados.
Polyunsaturated fats: also good for us and our body cannot synthesize them, so we have to eat them. We can find them in fatty fish, flax seeds, walnuts, chia and hemp seeds and soybeans.
Saturated fats: Still healthy but solid at room temperature so harder to digest. Comes from animal products.
Trans fats: Have been artificially altered to have a longer shelf life, very solid at room temperature and very hard for your body to digest and get rid of, this is the one that causes us more harm than good, avoid them if you can!
One gram of fat brings in 9 calories when you digest it so they make us feel more full.
This is a double edge sword because it is easier to over eat fats if we don’t pay attention to portion size.
One tablespoon of olive oil has 120 calories in it. If we’re not careful, we easily put 3 of those in our dressing for our salads, and now even if you only have 100 calories worth of vegetables in your salad, you just added 360 calories from the oil.
It is recommended that you eat 1 gram of fat per kilogram of body weight. Since I weigh 81 kilograms, I need to eat 81 x 1 = 81g of healthy fats each day.
Now that you have a better grasp on calories and macros, let’s talk about how it all ties in together.
energy balance and body composition
The energy balance refers to your energy input (food that you eat) and output (Energy we use to live)
Energy input is all calories coming into our bodies through foods and beverages.
Energy output is energy we use to go about our lives. It includes three categories.
Physical activity. These are all the calories you use when you exercise.
Resting metabolic rate. These are all the calories you use to sustain your everyday life.
Thermic effect of food. This is the calories required to break down the food you eat. This amount is negligible for body composition so we will not spend more time on it.
When your input is greater than your output (called calorie surplus), we store the extra energy as fat and gain weight. When the output is greater than the input (called calorie deficit), we use up our fat stores and tend to lose weight.
As we saw earlier, different macros bring in different amounts of calories, and nutrient density establishes the quality of those calories. Finding the right balance for your goals must take into consideration the following points.
Are you getting enough protein and healthy fats?
Are your calories aligned with the desired balance? If you want to lose weight, are you in a calorie deficit?
Are you getting enough micronutrients through nutrient dense foods?
Let’s take me for example. I am currently trying to maintain my weight. I am active, on my feet for 6 hours+ each day and workout so I need to consume 2500 calories per day. That is my caloric budget for each day. Let’s see how I can address each of these points with my nutritional habits.
Getting enough protein and fats
I weigh 81 kilos, so we know from earlier that I need 2g of protein per kilogram of body weight, so that would be 2 x 81 = 162 gram of protein per day. Each of these grams of protein contain 4 calories, so I have 162 x 4 = 648 calories that go towards protein in my calorie budget.
We established I need one gram of fat per kilogram of body weight, so 81 x1 = 81g of fats. Each of these grams contain 9 calories so 81 x 9 = 729 calories of my calorie budget go towards fats.
Here’s where it gets fun. Now I establish how many carbs I can eat. I already consume 648 calories of protein and 729 calories of fat, that is a combined 648 + 729 = 1377 calories out of my caloric budget.
I have 2500 - 1377 = 1123 calories left in my budget for carbs. One gram of carbs contains 4 calories so to find how much carbs I can eat I divide 1123 by 4 and get 280.75g.
These calculations give me a general guideline for my macronutrient ratio:
- Protein 162g
- Fats 81g
- Carbs 280g
Macronutrient ratios very greatly from individual to individual, depending on age, nutrition preference, activity levels, health goals, I encourage you to find one that works best for your lifestyle.
These numbers would allow me to maintain a neutral caloric balance.
If I want to tip the balance in a surplus or deficit, I would only adjust my carb intake. Whether you are trying to put on muscle or lose weight, you still need enough protein and enough healthy fats to feel your best.
If your carbs intake is a little lower, it won’t affect your body as a lower protein or fat intake would.
Muscle building and protein
2g of protein is more than enough to build muscle. If your goal is to build muscle, you don’t need to eat much more than that.
Focus on eating more carbs instead, which will give you plenty of energy to recover and train harder, which are two very important aspects of muscle building.
Now that I have enough protein and fats and that my caloric balance is where I want it to be, how is the quality of the calories I eat?
If I decide to eat a box of Oreos (so yummy) containing the classic three rows of fifteen cookies, that will be 2385 calories in total (each cookie has 53 calories).
Each cookie has 7g of fats, 2 grams of protein and 25 grams of carbs. After quick calculations, we find that eating that box of Oreos will give me 1125g of carbs, 90 grams of protein and 315g of fats.
In theory, this box of Oreos is within my daily caloric budget, but would it be a good idea?
I couldn’t eat much more that day, because I would already be at 2385 calories out of 2500, my macro ratio is way off and since Oreos are very processed, it wouldn’t give me a lot of minerals and vitamins.
On the other hand, what if I ate raw celery, with nuts, and a salad with close to no dressing, plus a piece of meat that wasn’t prepared in any fancy way?
After overcoming my misery at eating such a bland meal, I would be well within my caloric budget, my macros would be way more balanced and I would have plenty of vitamins and minerals. But would that make me happy? And could I eat more similar meals?
These are two extreme examples to show the range of choices you have at your disposal when it comes to food selection. The answer lies somewhere between these two examples depending on your goal and will be different for everyone.
As a rule of thumb, try to always have a serving of green veggies at lunch and dinner and aim for five servings of fruits each day to make sure you get enough micronutrients.
What if I don't count calories or macros?
Counting your calories and macros is not always necessary to change your body composition.
If you don't want to count anything, focus on developing healthy relationships with food.
A healthy relationship to food can take many form, at the end of the day, it's whether or not you are happy with your food choices. It could look like this:
Enjoying all foods in moderation
Enjoying eating out in social settings
Not worrying about what others may think about your food choices
Respecting your body's hunger cues
Eating until full, no more
Not needing to justify you choices
Not worrying about the number on the scale
Not incessantly worrying about getting enough protein
There are other examples, as we each develop our own relationships with foods. Try to identify your relationships with food and ask yourself, are they healthy, or unhealthy relationships?
Sometimes, counting calories and macros for a couple weeks, even a couple months teaches us a lot about the food we eat and can therefore help us develop healthier relationships down the road. We don't need to count calories all the time, just long enough to gain a better understanding of what we put in our bodies.
We eat a protein, fats and carbohydrates to give our body the energy it needs. Different foods contain different amount of micro nutrients which are essential for our bodies to function properly. Depending on your goals, you can identify how much of each macronutrient you need and how they will impact your caloric budget.
You don't always have to count your calories, but I do recommend you do it for a couple weeks so you can understand how your food choices affect your body and whether or not you have a healthy relationship with food.