A popular approach to weight control is the flexible diet If It Fits Your Macros (IIFYM) – a dietary theory that tries to avoid complexity by focusing only on macronutrients.
We know that adherence to a diet is more important than the diet itself1 and so the simplicity of IIFYM makes it a very useful tool to start taking control of your nutrition.
The world isn’t as simple as IIFYM tries to paint it, however, and there are some drawbacks to the method. I still think it’s a great start though and later on we’ll have a look at how to improve it.
Like most diets, IIFYM will help you lose weight. Contrary to most diets, it’ll also help you gain weight if that’s your cup of tea. Whatever direction you want to go, up or down, there are many reasons why you’d want to control your weight.
- You might be trying to grow stronger and would like to add muscles. (This is me!)
- Others want to look and feel better in their birthday suit.
- Some might have to lose some weight for health reasons.
- Yet others need to maintain weight to stay in the weight class they’re competing in.
Let’s see how this is done with IIFYM.
Macros is an abbreviation for macronutrients and there’s three of them: protein, carbs, and fat.
Protein is the building block for most parts of our bodies. It both helps in growing muscles and retaining them when you’re trying to lose weight.
Carbs is the next fastest source of energy (after creatine) and thus very important for our performance both in the gym and, since our brains run on carbs, at work.
Fat is needed for our nerves and brains to function properly, dissolve vitamins, form hormones, etc, etc. It’s essential for our bodies and shouldn’t be feared.
All macronutrients carry with them some energy we can use. This energy is measured in calories (actually kilocalories – kcal – but we’ll make it easy and use the terms synonymously here).
The amount of calories you absorb from food, minus the calories you burn during the day, is your caloric balance. If this balance is negative you’ll lose body mass and if it’s positive you’ll gain body mass. It’s really simple.
Except it’s not that simple.
There’s many factors that will modify the amount of calories you absorb and the calories you burn.
I’ll touch on this in a later article – don’t miss it by subscribing! For now just know that you can’t simply look at the calories on the food label, subtract what the treadmill display says, and think that you know your exact caloric balance. It’s a crude estimate.
Finding your macros
Step 1 – TDEE
By putting yourself in a positive or negative caloric balance you’ll grow or shrink. That’s why we’ll start by estimating your Total Daily Energy Expenditure (TDEE), the amount of calories you need to absorb per day in order to maintain your current weight.
Use this calculator to find your value. Enter your age, weight, height, activity level, and optionally body fat percentage. Then look for Your Maintenance Calories – this is your TDEE.
(Oh, and please ignore the BMI nonsense on the results page.)
Let’s use myself for example. I’m a 90 kg male of 31 years, measuring in at 184 cm and doing Moderate Exercise (Heavy As Fuck wasn’t an option). This gives me a TDEE of about 2950 kcal.
Since I want to grow I’ll add 250 to this number and end up with 3200 kcal. You might want to shrink and would then instead subtract 250.
PS: One kilo body fat is 7000 kcal, meaning a 1000 kcal deficit per day would make you lose 1 kg per week. That’s a lot though and it’d have bad side-effects, so don’t exceed -250 per day.
Step 2 – Protein
Next we’ll start breaking down these calories into macronutrients, beginning with protein. This is not only important for growing bigger but protein is also important when trying to lose weight.
As stated in my article on protein, the recommended amount is around 2 grams per kilo lean body mass. My 90 kg are definitely not all lean body mass though, so let’s do some math.
For simplicity let’s say I’m at 20% body fat:
20% fat = 80% non-fat
This puts me at 72 kg lean mass:
90 kg * 80% = 72 kg lean body mass
So I’d aim for 144 grams of protein per day:
72 kg * 2 g = 144 g protein per day
Each gram of protein has 4 kcal, which would be about 600 kcal in my case.
3200 - 600 protein = 2600 kcal
Step 3 – Carbs
Next up is our carbohydrates. They’re the most important source of energy both for enduring our tough training sessions and using our brains in day-to-day life.
Exactly how much you need depends on how intensive training you need to fuel. However, a good start for vegans in training is 6 grams per lean body mass:
72 kg lean body mass * 6 g = 432 g carbs per day
Each gram of carb gives, just like protein, 4 kcal of energy. In my case that’s about 1700 kcal.
2600 - 1700 carbs = 900 kcal
Step 4 – Fat
This is the easiest step – we simply get the remaining calories from fat. Each gram of fat gives us a whopping 9 kcal of energy. It packs quite a punch!
That gives us:
900 kcal / 9 per gram = 100 g
Steg 5 – Tweak
Let’s summarize our macros: 144 g protein, 432 g carbs, and 100 g fat.
Step #5 is the most important one: try these numbers out, see how they work for you, and tweak the macros to fit your lifestyle.
Feeling hungry a lot? Eat more fat and less carbs.
Not gaining any weight? Try adding 500 instead of 250 to your TDEE.
Feeling tired during training? Increase the carbs, decrease fat.
Measure yourself routinely and see what happens on a weekly basis. If your weight’s not moving in the direction you want it to, just tweak your TDEE number for next week.
This is a gradual process and all these numbers are really just coarse estimates. Step #5 is all about getting to know ourselves and finding our own values.
A note on the macro split
In energy, our split is: 600 kcal protein (19%), 1700 kcal carbs (53%), and 900 kcal fat (28%).
I’m sure you’ll encounter other recommendations for how to split the macros. The most popular in IIFYM circles is 40:40:20 for protein:carbs:fat.
My reasons for this recommendation are simple. We don’t need more protein, fat keeps you fuller longer, and the high carbs will allow you to perform better. Something like a 20:55:25 split is simply closer to optimal for vegan athletes.
NB: I’m not a certified dietitian! However, I consider the above reasoning quite solid and well-founded in modern science. As such I invite any criticism with open arms: [email protected]
Another very important thing to know is that our bodies are incredibly adaptable. If you start to eat a lot of fat and very little carbs, your body will change to use more fat for energy. And vice-versa.
Fitting your macros
Now that you’ve found your macros, let’s fit your diet around them. Here’s some examples of where you can look for the three macros in vegan foods:
For protein: soybeans, chickpeas, lentils, black beans, tempeh, peanuts, seitan, tofu, sunflower seeds.
For carbs: Rice, pasta, potatoes, bread, quinoa, oats, and most fruit and berries. The lower their glycemic load the better.
For fat: Avocado and olive oil, coconut cream, peanuts, almond, walnut, cashew.
Pick one and have a look at its label. Either the label on the package or online, where you can [search for “nutrition
Let’s say I’m having chickpeas for lunch. Per 100 g cooked it’s got 2.5 g fat, 11.7 g carbs, and 6.2 g protein. I like to eat a whole can, which is 400 g. Since 400 g is four times as much as 100 g, we need to multiply all macros by four.
So we get
2.5 * 4 = 10 g fat,
11.7 * 4 = 46.8 g carbs, and
6.2 * 4 = 24.8 g protein.
There’s loads of fitness apps out there that can keep track of this for you but basically you’d just keep adding up the macros like this. As you prepare your meals during the day you have a look at the tally and see what you need to fit in to reach your goals.
It’ll never ever be 100% on point but IIFYM is a crude tool anyway and we’re only using it for guidance, not absolute measurement. In the end, what we’re after is getting to know our bodies, how they react to what, and how best to fuel them.
Just keep tweaking your macros and you will gradually take more and more control over your weight.