If it fits your macros (IIFYM) diet review: Is quantity more important than quality?

With all the buzz on the internet about “IIFYM” – pictures of burgers, doughnuts and other delicious treats that fill our newsfeeds from different fitness “influencers” – we wanted to take this opportunity to provide you with some context, information and resources to help YOU decide what is best for you.

Is IIFYM the way to go? You be the judge!

IIFYM was started by a couple of bodybuilders who grew tired of the “clean eating” movement. They felt the food was boring, unappealing and “too healthy.” Their diet was simple: eat whatever you want. But there’s a catch – you have to stay true to your macronutrient distribution.

Macro what?

Macronutrients are the major nutrients that are found in food and provide us with energy. These include the big three: protein, fat and carbohydrates. All of these macronutrients added together provide us with our total calorie intake.

Proteins + Fats + Carbs = Total Calories
Keeping that in mind, here is the acceptable macronutrient distribution ranges for adults in maintaining a healthy diet:
Protein: 15-35%
Fat: 20-35%
Carbohydrate: 40-60%

DISCLOSURE: Your macronutrient distribution depends on a variety of factors like your age, weight, sex, and physical activity level. If you would like a breakdown of your macronutrient distribution, set up an appointment with a Registered Dietitian.

So what is IIFYM then?
The philosophy behind the diet is that you can eat whatever you want and lose weight as long as you don’t go over the recommended intake for each of those macronutrients for the day. Their website uses a calculator to determine your needs but I must warn you that to use it you need to provide them with your e-mail and all that jazz.

BE CAUTIOUS: IIFYM is about quantity of calories, not quality of calories.

In the words of If it Fits Your Macros followers: “regardless if you like to eat pizza, or boiled chicken breast, If it Fits Your Macros teaches us that if you eat less calories than your body requires you will lose weight at a steady and predictable rate”.

Is this really true?

Pros of IIFYM
One key positive is that this diet is unique because it takes away the restrictive nature of most fad diets. Diets like the Adkins diet, Master Cleanse or the Banana diet totally restrict calories and key macronutrients which may temporarily cause weight loss but it is practically impossible to sustain… like IMPOSSIBLE, especially when we need macros like carbohydrates for our brain to function and survive.

As well, macronutrient needs are important because they help us create balance in our diet and make sure we’re not getting 90% of our calories from fat. Watching macronutrient distributions are even more important for endurance athletes who rely on high levels of carbohydrates to endure their long workouts and replete their glycogen needs. Macronutrients are also important for bodybuilders who want to increase their muscle mass by increasing their protein needs.
Weight Loss on IIFYM?
We know from practice and research that when we reduce calories, we see weight loss, so IIFYM was right then. However, when we reduce calories, we tend to be unhappy and unsatisfied and we fall off the wagon and regain our weight, because it is NOT sustainable

There have been several experimental trials and high quality studies, that looked at the difference between either a high fat/low carb diet or a high carb/low fat diet, and there was still no difference in weight loss.

But…Empty Calories?
I don’t know about you, but when I’m told I can eat anything I want, that usually means binging at the local drive thru. When this happens, we’re consuming “empty calories” – this means they contain little to no fibre, vitamins or minerals that we need for our bodies normal function. When foods are heavily processed like a pop tart for example, they are stripped of their nutrients and loaded with sugar, fat and salt. So if we are replacing our diet with these empty calories, our body is not getting what we need to help us run smoothly and protect ourselves from chronic diseases.

Another downside of empty calories: less satiating. Meaning the moment we eat a bag of chips, an hour later we’re reaching for more chips… which doesn’t help with the whole eating fewer calories goal. Meals that contain high protein and fibre help us feel more full and prevent the binging at the all too dangerous mid-afternoon snack cart.

Another secret with eating nutrient dense foods: you can eat more. Yes, it’s true!

Let’s compare two snacks with the same calories and carbohydrate content, and you can be the judge of which you think would make you more full:

Snack 1: 3 oreos
Snack 2: 1 bowl of cottage cheese + 1/2 cup of mixed berries + 1 small honey crisp apple

I think we can all agree that snack 2, which contains a source of protein, fibre and vitamins and minerals will make you feel more full and satisfied and will probably not lead you back to the fridge twenty minutes after eating it. And let’s be honest, who can only eat three oreos and not the whole row… I know I can’t.

Eating whole foods with a variety of macros lets you eat more and feel more satisfied. Now that sounds like a recipe for sustainable weight loss.

IIFYM Summary
The takeaway message is that between “clean eating”, which can create an unhealthy obsession with the quality of calories and IIFYM eating which focuses too much on quantity of calories, we need to find ourselves somewhere in the middle. Let’s follow the 80/20 rule – 80% of the time be conscious of the quality of calories by aiming for whole nutrient dense foods, and 20% of the time enjoy those indulgences.

Especially for athletes, being conscious of the food you’re eating is SO important and if you focus on eating high quality sources of carbohydrates that are loaded with fibre and vitamins and minerals it will even enhance your training and performance. Just remember that counting calories won’t be as effective for weight loss if you’re not thinking about the quality of those calories.

Think of it this way, if you are choosing nutrient dense foods, you will feel more full and in the end you will end up eating less calories, which is a win-win for you and your body. That sounds like a good bargain to me!

Yours in health,

Alysha Coughler
Food for 6S Registered Dietitian

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