Have Your Cake And Eat It Too (IIFYM)

Have you ever heard the term flexible dieting (FD) or if it fits your macros (IIFYM) and wondered what it meant? In today’s post you’ll learn how you can have you cake and eat it too!


Calorie Balance


Before we delve deeper into the concept of flexible dieting we need to lay the foundation of all diets… Calorie Balance.

The Negative Side

Each and every day your body is burning energy to keep you alive and fuel all your activity. Your Resting Metabolic Rate (RMR) accounts for nearly all the energy your body uses on a daily basis and includes: brain function, breathing, cellular repair, blood flow and heart function, temperature regulation, and much more.

But we know you don’t sit around all day, right? Your body requires even more energy when you perform Physical Activity. Something important to note is that even walking around, brushing your teeth, and standing around burns energy; you don’t have to be busting your butt in the gym to be burning calories through physical activity.

Last but not least, is the Thermic Effect of Food (TEF) which accounts for all the energy your body uses when digesting food throughout the day. Certain foods (especially foods high in protein and alcohol) may increase TEF output.¹

All of these combined are referred to as our Total Daily Energy Expenditure (TDEE/TEE).

The Positive Side

This is where energy comes into play. Our bodies are using energy all day long to sustain life and perform the actions listed above (yes, even when you sleep!) which means our bodies need a constant stream of energy to keep us alive.

Where does this energy come from? Two main places.

First is the foods and drinks we consume which contain the Macronutrients proteins, carbohydrates, and fats. Everything you consume is made up of the macronutrients which provide your body the energy (in the form of calories) it needs.

How much? Each Macronutrient provides the following calories per gram:

  • Carbohydrates: 4 calories per gram
  • Proteins: 4 calories per gram
  • Fats: 9 calories per gram

In addition to providing us energy, our bodies can use these macronutrients to perform specific processes (like hormone regulation, tissue repair, creating enzymes, and more).

The second source our bodies use for energy is our bodies soft tissue including muscle tissue and body fat. In general our body prioritizes the use of Adipose Tissue (body fat) when energy sources are scarce.

The Balance

So… since our bodies are a closed and isolated system they must maintain a proper energy balance for optimal health. When energy sources are over-abundant and above what we currently burn through RMR, TEF, and Physical Activity our bodies must store this excess energy for later use (where else would it go?).

Common Myth: you poop/pee out excess energy and your “metabolism” is tied to your bowel movements. Wrong. Our bodies are incredibly efficient at absorbing nutrients and energy from the food we eat assuming we don’t have any digestive disorders like Chrons Disease, Inflammatory Bowel Disease, Celiacs Disease, etc.

So…where does this excess energy go? It is stored as triglycerides in our bodies’ Adipose Tissue.

The reverse is also true. When we’re burning more energy through our TDEE than we’re ingesting our bodies must get energy from somewhere. Where does this come from? A combination of adipose tissue and some muscular soft tissue.

So, What is IIFYM?

Essentially, you determine your calories to lose/gain weight (here’s a free tool to do just that). From there you determine how many grams of each macronutrient you need to eat in order to reach your goal. Most people find that they meet their USDA-RDA needs by eating around 40% carbs, 30% proteins, 30% fat, but this obviously changes depending on the total calories they’re consuming.

Note: According to the American College of Sports Medicine, women should never eat below 1,200 calories and men should never eat below 1,800 calories per day.

Once you’ve got your calorie/macro goal… you eat foods that fit your macronutrient goal and track these foods with a food diary. It’s that simple! 

The Good

One of the great things about IIFYM is that individuals are able to eat a diet that is both sustainable and enjoyable while losing weight. Instead of a long list of foods you “cant eat” you’re able to adapt your diet to fit your specific goals.

With IIFYM you no longer have to worry about individual items being “good” and “bad” and instead can focus on the whole picture of energy balance. It is no longer a question whether individual foods are healthy, but whether your entire diet is “healthy” as a whole.This means some individuals are able to eat with less guilt and shame surrounding food.

For this reason, it’s my opinion that IIFYM is not only one of the most effective concepts for weight loss, it’s one of the most successful long-term.

The Bad

Ah yes, there’s always a catch isn’t there? While IIFYM can be amazing to break down the illusion of “good” and “bad” foods it can lead individuals to binge-eat poptarts, oreos, and other calorie dense foods simply because they “fit their macros”. Believe me, just search any social media for “#iifym” and i’m sure you’ll find a plethora of posts where people are eating a bowl of icecream topped with chocolate sauce, a box of twinkies, a crumbled up poptart, and a side of protein powder.

IIFYM is awesome, but the macronutrients in and of themselves are supposed to be a limiting factor. How can one possibly over eat pop-tarts when they’re eating so few calories? By neglecting any other foods including micronutrient and fiber rich fruits, veggies, legumes, and whole grains, that’s how!

Gaining balance is incredibly important when counting macronutrients. The question shouldn’t be “can I” but “will i be hungry if i spend all my macros on non-filling foods” or “Will i feel my best if i don’t eat enough vitamins, minerals, or fiber”?

Not only do most calorie dense foods offer little effect on our satiety they often lack the plethora of antioxidants, vitamins, minerals, and fiber of whole plant foods. They often lack healthy and anti-inflammatory omega 3 fats found in plants, nuts, seeds, and fatty fish. These foods also offer little in the way or probiotic bacteria necessary for optimal gut health.

To Conclude

The gist is that while macronutrient intake and calorie balance is the single most important thing you can do lose weight; it’s not the end all be all! You’ve still got to include these nutrient dense, high volume, highly satiating, and often low-calorie foods in your diet if you wan’t to feel your best long-term. Everything in moderation and happy IIFYM-ing! 😉