If you want to know what the “If It Fits Your Macros” diet is and whether or not it can help you lose weight, you want to read this article.

Key Takeaways

  1. “If It Fits Your Macros” (IIFYM) is a dietary strategy that revolves around eating a certain number of calories and amount of protein, fat, and carbs daily from whatever foods you want.
  2. If used properly, IIFYM is the most reliable way to lose weight. If used improperly, it can make weight loss more difficult and lead to health problems.
  3. The proper way to use IIFYM is to get at least 80% of your daily calories from whole, nutritious, minimally processed foods.

What if you could eat hamburgers, pizza, and ice cream every week—hell, maybe even every day—and still have abs?

Such is the rallying cry of many people who subscribe to the “If It Fits Your Macros” (IIFYM) style of dieting.

And they often share pictures to gloat about it, like this . . .

macro diet plan

. . . which leave many unfit people confused and frustrated.

How is that possible? 

Aren’t carbs and sugar the most fattening foods you can eat? Do these people work out hours per day or just have outstanding genetics or what?

(No and not necessarily, but let’s not get ahead of ourselves.)

Others claim the principles of IIFYM shouldn’t be used to merely get and stay lean while eating like a spoiled child. Instead, they should be used to look and feel great while eating a wide variety of foods including those verboten by more traditional, restrictive forms of dieting.

For instance, this might mean regularly eating foods like pasta, bread, dairy, and sugar while also maintaining a healthy intake of more nutritious foods like lean meats, fruits, and vegetables.

Who’s right?

Often the most accurate answer to such questions is “it depends” or “somewhere in the middle,” but in this case, there’s a clear winner: moderation.

In other words, IIFYM works best as a more flexible, accommodating approach to “clean eating,” as opposed to its polar opposite, where you follow meal plans that emphasize whole, nutritious foods while allowing for less wholesome indulgences.

And in this article, you’re going to learn why and get simple, science-based answers to all of your questions about IIFYM, including . . .

  • What is IIFYM?
  • Does IIFYM work as well as people say? 
  • Is IIFYM healthy?
  • What’s the best way to use IIFYM principles?
  • Should you follow the IIFYM diet?
  • And more.

Let’s get started.

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What Is the “If It Fits Your Macros” Diet?

The key to understanding IIFYM is understanding what “macros” are.

“Macro” is a contraction of “macronutrient,” which is defined by the Oxford English Dictionary as “a type of food (e.g. fat, protein, carbohydrate) required in large amounts in the diet.”

Simple enough. 

Next, to understand IIFYM, you need to understand the following simple principles:

  1. Your body weight is dictated solely by how much you eat, not what you eat. In this way, a calorie from brown rice is no different than a calorie from a brownie.
  2. If you want to improve your body composition (lose fat and/or build muscle), you need to eat the right amount of calories per day according to your goals and pay attention to where those calories come from in terms of protein, carbs, and fat.
  3. If you hit your calorie and macro targets (protein, carb, and fat targets) every day, you’ll see results regardless of the foods you eat.

In short, IIFYM is an evolution of the “calories in, calories out diet” that makes it more workable for us fitness folk.

Accordingly, to follow the IIFYM diet, you start by determining how many calories you should eat every day based on whether you want to gain muscle, lose fat, or maintain your weight, and then calculate how many of those calories should come from protein, carbs, and fat.

Why this extra step of calculating macros? Why not just stick with calories alone?

Well, while a calorie is a calorie if we’re only looking at body weight, calories can be quite different when considering body composition.

That is, if all you want to do is lose weight, a calorie deficit of any kind will get the job done, but if you want to lose fat and not muscle (or even gain muscle), you have to be more discerning.

Specifically . . .

Just counting calories often leads to inadequate protein intake, which can cause a variety of problems including slower muscle gain, impaired post-workout recovery, increased hunger, and more.

  • You need to eat enough carbs, too.

    Contrary to popular belief, if you’re physically active, and especially if you train your muscles regularly, you’re probably going to do better with more carbs in your diet, not less.

    And yes, that’s true even when you’re restricting your calories for weight loss.

    There are a number of reasons for this, including improved workout performance, recovery, mood, and muscle growth.
  • You don’t need to eat as much healthy fat as many would have you believe.

    There’s no denying the importance of eating adequate dietary fat, but there’s also no major benefit to eating more than your body needs to maintain optimal health.

    And as you’ll learn later in this article, that amount is far lower than many high-fat advocates claim.

IIFYM covers all these bases (calories, protein, carbs, and fat) and thus is superior to merely calorie counting, and especially for improving your physique and fitness.

Summary: “If It Fits Your Macros” (IIFYM) is a dietary strategy that revolves around eating a certain number of calories and amount of protein, fat, and carbs daily from whatever foods you want. 

IIFYM vs. Flexible Dieting


IIFYM is synonymous with another dietary method known as “flexible dieting,” which also involves eating foods you enjoy while hitting your calorie and macronutrient targets.

The central premise of IIFYM and flexible dieting is identical: 

To improve your body composition, hit daily calorie and macronutrient targets eating foods you enjoy.

The application of that maxim among people following IIFYM versus flexible dieting differs greatly, however.

The reason for this has to do with how these “brands” of dieting originated.

The “IIFYM” acronym came from Internet forums where fitness newcomers would ask more experienced dieters and bodybuilders whether they could or couldn’t eat different foods while dieting. 

“Can I eat bananas?” 

“Can I eat bread?” 

“Can I drink milk?”

And so forth. 

Veterans got tired of answering these redundant questions, so they began replying with a five-word response: “If It Fits Your Macros.”

In time, this was shortened to just “IIFYM,” and voila, a meme was born.

It caught on quickly because it was more or less the exact opposite of the “standard” method of dieting for fat loss, which went something like this:

  • Stop eating “bad” or “unhealthy” foods that “make you fat” or “prevent fat loss,” like fruit, bread, dairy, and anything with natural or added sugars. 
  • Eat nothing but “clean” foods like vegetables, legumes, lean meats, and seafood.

This approach can work for some people in the short term, but for most, it’s far too restrictive to stick to for any period of time. 

And even those who do successfully lose weight this way rarely can keep it off once they stop dieting. In many cases, they wind up gaining back all the weight they lost and then some.  

Flexible dieting is an effective alternative to this traditional, often unworkable and always unsustainable weight loss regimen.

Instead of heavily restricting calories and food choices, flexible dieting allows you to lose weight eating the foods you like by moderately restricting calories and regulating macronutrient intake. 

In other words, you’re free to eat whatever you’d like so long as your meal plans meet your daily calorie and macronutritional targets.

In this way, flexible dieting is more or less identical to IIFYM, but as it has its origins in the evidence-based fitness space, it also recognizes the importance of eating nutritious foods and often includes other diet strategies such as planned diet breaks and cheat meals.

Think of it this way: IIFYM is the Tinder of dieting—easy, effective, but ultimately unsustainable and unhealthy—whereas flexible dieting is a wholesome relationship. 

Summary: Flexible dieting involves using IIFYM principles as well as several others to make dieting more enjoyable, sustainable, and effective, but they aren’t identical.

Does IIFYM Work?

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Some people claim that IIFYM isn’t all it’s cracked up to be.

Some say it doesn’t work for anyone, others say it doesn’t work for everyone, and others still say it works invariably but isn’t a proper way to lose weight.

Who’s right? 

The short answer is all these people are wrong—IIFYM works, it’s helped thousands of people build their best bodies ever, and if done intelligently, is one of the simplest ways to improve your body composition.

This is why I’ve been using IIFYM for years now to maintain a lean, muscular, and healthy physique, with my daily “macros” generally looking like this:


This is enough calories to maintain my weight, protein to fuel muscle recovery and growth, carbohydrate to fuel workouts, and dietary fat to maintain health.

Now, here’s the part of IIFYM that throws many people for a loop:

So long as I hit those calorie and “macro” targets every day, the foods I eat won’t negatively affect my body composition.

My protein could come from 99% lean ground turkey or fatty ground beef, my carbs from sweet potatoes or candy, and my fat from avocado or ice cream, and so long as I “hit my macros,” I won’t gain fat or lose muscle.

Furthermore, if I wanted to lose fat, I’d simply reduce my calories and macros accordingly, and if I wanted to maximize muscle growth, I’d increase them.

What about the common arguments against IIFYM, though? The most popular ones are: 

  1. Calories don’t count (or they’re too hard to track)
  2. IIFYM will wreck your health (and eventually your physique)
  3. IIFYM will wreck your relationship with food

Let’s review each in detail.

“Calories Don’t Really Count (or They’re Too Hard to Track)”

The most unscientific and, quite frankly, absurd argument against IIFYM is calories aren’t as important for weight loss as many people think.

What matters more, some “experts” say, are avoiding certain “toxins” in food, preventing nutritional deficiencies, minimizing carbohydrate or sugar intake, optimizing hormones, and other such misdirections.

The story usually goes like this:

You can restrict calories all you want, but if you don’t follow these precise and seemingly (actually) arbitrary dietary instructions, you’ll probably fail to lose weight, and even if you do, you’ll almost certainly gain it all back when you stop restricting your calorie intake.

A variation on this is the acknowledgment that consistently eating fewer calories than you’re burning results in weight loss, but this is a fool’s errand for most people because they can’t do it reliably and sustainably.

To get to the bottom of all this, we need to begin with a quick discussion of “calories in, calories out” and how it relates to your body.

Your body burns a certain amount of energy every day, and this can be measured in calories. 

The energy contained in food can be measured in the same way.

Technically speaking, a calorie is the amount of energy required to heat up one kilogram of water one degree Celsius.

To lose fat, you need to consistently feed your body less energy than it burns over time. When you do this, you create an energy (calorie) deficit that forces your body to tap into its fat stores to get the energy it needs.

In other words, body fat is your body’s go-to energy source when it can’t get the energy it needs through food you’ve eaten.

So, for instance, if you burn 2,500 calories in one day but only eat 2,000 calories, you’ll lose about 500 calories worth of fat (it doesn’t work as cleanly as this but close). Do this frequently enough and you’ll markedly reduce your total fat stores.

On the flip side, if you eat more calories than your body burns, you create an energy (calorie) surplus that results in fat gain. Do this frequently enough and you’ll markedly increase your body fat levels.

This isn’t just theory or my opinion, either.

A century of metabolic research has proven, beyond the shadow of a doubt, that the relationship between calories in and calories out—generally referred to as energy balance—is the basic physiological mechanism that regulates weight gain and loss.

This is why Professor Mark Haub was able to lose 27 pounds in 10 weeks eating 1,800 calories worth of Hostess cupcakes, Doritos, Oreos, and whey protein shakes per day.

And why the science teacher John Cisna lost 56 pounds in six months eating nothing but 2,000 calories worth of McDonald’s per day.

And why Kai Sedgwick got into the best shape of his life following a rigorous workout routine and eating 2,700 calories worth of McDonald’s every day for a month.

All that doesn’t mean you have to count calories to lose weight, but it does mean you have to understand how calorie intake and expenditure influence your body weight and eat accordingly.

I also don’t recommend you follow in those guys’ footsteps (for reasons we’ll go over in a moment), but I mention them to drive home this point:

When it comes to body weight, energy balance is king.

And that’s why IIFYM—and any other diet that reliably controls calories—works every time, for every person, under all circumstances.

Some naysayers admit as much. 

They concede that restricting calories causes weight loss and overeating causes weight gain, but also claim you can’t estimate calorie intake or expenditure with enough certainty and accuracy to make profitable use of the maxim of energy balance.

Thus, they say, it’s better to rely on intuitive eating for weight loss and maintenance.

They’re wrong.

First, you don’t necessarily need to calculate your energy expenditure for IIFYM to work. All you have to do is calculate your energy intake and then raise or lower it based on how your body responds. 

That is, once you’re accurately measuring how much you eat every day (in calories), you can raise or lower your food intake based on what happens to your weight over time.

Second, although there’s always going to be margin of error when estimating your calorie expenditure, you can get close enough to produce consistent and considerable improvements in your body composition.

Take me for example.

Here’s my personal transformation from skinny to muscular-but-kinda-fat to lean and jacked: 


I changed quite a bit with my training during this time, but the biggest improvement in my regimen was learning to properly manage my calorie and macronutrient intakes. 

This process taught me another invaluable lesson:

Intelligent application of IIFYM principles sensitizes you to your body’s energy balance and natural appetite cues, and this enables you to effectively wean off food scales, spreadsheets, and food tracking apps.

In other words, by spending time carefully planning and tracking your food intake, you gain vital wisdom that makes for successful intuitive eating like understanding what it feels like to be in a calorie deficit versus surplus and the calorie and macronutrient breakdowns of different types of foods and meals.

Summary: Energy balance—the relationship between how many calories you eat and burn—determines whether you gain, lose, or maintain your weight. Although you’ll never be able to track your calories in and out perfectly, you can get close enough to produce consistent and considerable improvements in your body composition.

“IIFYM Will Wreck Your Health (and Eventually Your Physique)”

This is a favorite strawman of IIFYM critics.

“You might be able to get shredded eating PopTarts, cereal, and candy,” they cry, “but eventually this will wreck your health and even your beloved physique.”

Uh yeah, no shit.

If you use IIFYM to eat like Veruca from Willy Wonka, you’ll experience a number of negative consequences that’ll get worse and worse over time.

Why is this criticism of IIFYM a strawman, then?

Well, based on my experience working with thousands of men and women over the years who’ve used my teachings to get into the best shape of their lives, most people don’t eat this way and would never even want to.

Instead, they use IIFYM to make “healthy dieting” more effective and enjoyable by accounting for energy balance and accommodating their personal food preferences, including indulgences and treats.

There are noisy exceptions, however—the muscular, lean IIFYMers who gloat publicly about all the junk food they eat.

Will this destroy their health and “aesthetics”? Maybe, but it’ll probably take a lot longer than you’d expect.

To wit, most research indicates that so long as your diet is generally nutritious, including junk food in it isn’t likely to negatively impact your health or body composition.

A good example of this comes from a study conducted by scientists at the Pennington Biomedical Research Center.

The scientists had six overweight men consume one “unhealthy” meal and two “healthy” meals that looked like this:

  • Unhealthy Meal: Big Mac, McDonald’s french fries, and root beer sweetened with high fructose corn syrup.
  • Healthy Beef Meal: A hamburger made with certified organic grass-fed beef, cheddar cheese, and a hamburger bun made with unbleached all purpose flour and natural ingredients, organic mayo, ketchup, lettuce, onion, and dill pickles. The meal also included organic french fries and root beer sweetened with cane sugar.
  • Healthy Turkey Meal: A sandwich made with free-range, antibiotic and hormone-free turkey breast, cheddar cheese, organic lettuce, mustard, mayo, and 60% whole wheat bread made with natural ingredients. The meal also included granola made with organic and all-natural ingredients and organic orange juice.

In other words, one fast food meal and two mostly organic, all-natural meals made with beef or turkey.

Here’s what the calories and macros of these meals looked like: 

Meal Calories Protein Fat Carbs
Unhealthy Meal 1,044 28.2 53 151
Healthy Beef Meal 1,154 28 60.2 163
Healthy Turkey Meal 1,260 34 49 170

All participants ate the same control breakfast at 8 am (so the results wouldn’t be affected by what they ate for breakfast), and then ate their assigned lunch at 12 pm. Each participant ate all three of the lunches, with a week between each test.

After each of the lunch meals were eaten, scientists took careful measurements of the subjects’ blood levels of glucose, insulin, free fatty acids, ghrelin, leptin, triglycerides, and LDL and HDL cholesterol every 30 minutes for the first four hours and then every 60 minutes for the next two hours.

The result? 

There was no difference in insulin, glucose, leptin, or HDL cholesterol levels between the different meals. 

Blood triglycerides were slightly higher after eating the healthy turkey and beef meals and slightly lower after eating the unhealthy meal, although it’s possible this is because the unhealthy meal contained the fewest calories.

Ghrelin levels (a hormone that stimulates hunger) were suppressed equally at first, but rose higher five hours after the unhealthy meal than the healthy meals, indicating the latter did a better job of suppressing appetite.

LDL cholesterol levels also decreased slightly more after eating the healthy meals than the unhealthy one. 

What about glycation, oxidation, inflammation, and other big bad buzzwords certain fitness gurus love to use to scare people away from IIFYM and into their loving arms (and coaching programs)?

Mostly humbug resulting from carefully cherry picked and mostly misunderstood or misrepresented research.

For example, I recently saw an interview with a “fitness influencer” and online coach who claimed eating broccoli could improve your physique thanks to a molecule in it called indole-3-carbinol

A few studies have shown this compound may decrease the concentration of molecules that stimulate estrogen production in the body, but no research has been done to explore how this may or may not influence body composition.

Moreover, the studies that have been done involved giving people synthetic, concentrated indole-3-carbinol, not broccoli.

Naturally, that didn’t stop the interview guest from stating conclusively that eating broccoli will reduce estrogen production enough to help you shed body fat faster. 

Now, the takeaway here isn’t that you can eat as much junk food as you want and remain perfectly healthy.

The point is simply that a single “unhealthy” meal has almost no impact whatsoever on your body, and thus what really matters are your chronic eating habits. 

  • Are you using energy balance to maintain a healthy body composition? 
  • Are you getting most of your calories from whole foods like lean meats, fruits, vegetables, legumes, grains, etc.?
  • Are you eating enough vegetables in particular?

If your answers are yes, yes, and yes, and if you’re also exercising at least a few hours per week, no amount of occasional “cheat meals” of even the most nutritionally bankrupt fare can bring you down.

Something else to keep in mind: 

Many people who use IIFYM to eat copious amounts of highly processed, sugar-laden grub are in their “honeymoon phase.”

After years of bouncing from one type of highly restrictive diet to another with little to show for it, they feel like they’ve discovered the holy grail of dieting and take full advantage of it.

In most cases, however, the novelty wears off in a couple months and they get bored of eating piles of junk every day and welcome the return of nourishment. This naturally leads to the adoption of a normal, healthy, and sustainable diet that may include but doesn’t revolve around food courts.

What if their honeymoon never ended, though? 

Well, there’s no question that a diet severely lacking in vitamins, minerals, fiber, and other micronutrients and stiff with sugar, chemicals, and refined oils will undermine your health, vitality, and longevity.

This is news to nobody, though, on par with the connection between smoking and drinking and the risk of various diseases.

Summary: Eating lots of junk food is bad for your long-term health, but aside from making it easy to eat too many calories, it isn’t going to make it harder to lose fat, build muscle, or stay lean.

“IIFYM Will Wreck Your Relationship with Food”

Another major criticism leveled at IIFYM is it screws up your relationship with food and even promotes eating disorders.

And once again, there’s a kernel of truth here.

IIFYM naturally encourages you to start viewing food through the lens of just calories and macros, which can lead to some pretty odd and unappetizing meals to “hit macros.” 

Peruse the #IIFYM hashtag on Instagram and you’ll see what I mean. As of right now, I’m seeing stuff like . . . 

  • Boiled chicken breast and white rice (cooked together)
  • Lunch meat, raw cucumber slices, and Goldfish crackers
  • Low-calorie Oreo pudding, protein powder, and peanut butter (mixed together)

You know, the types of meals that take you back to your college days, when it was practically a rite of passage to eat like a Third Worlder.

Why are IIFYMers keeping this tradition alive?

In most cases, it’s just a matter of convenience. Creating and cooking tasty, nutritious, macro-friendly recipes takes know-how and work, whereas throwing together foul but macro-friendly Frankenmeals is a cinch.

This isn’t IIFYM’s fault, though. Blame the people who are too lazy to cook or find new, healthy, macro-friendly recipes instead.

Sure, you could say IIFYM is the enabling factor here—that without it, these people wouldn’t be able to commit such dietary sins without at least sacrificing their body composition, which would likely deter them in the first place—but by that logic, sugary foods lead to obesity, condoms cause promiscuity, and drivers licenses are to blame for DUIs.

In other words, IIFYM merely allows you to eat more freely without gaining fat or losing muscle, but if you abuse that freedom, well, that’s on you.

Another common criticism of IIFYM is it leads to an almost neurotic obsession with meal planning.

Since IIFYM allows for unlimited food choices, some people spend inordinate amounts of time coming up with new stuff to eat and places to try—in some instances more time than they spend in the gym!

Again, however, this isn’t an inherent flaw in IIFYM but simply in how some people practice it. If used intelligently, though, there’s no reason it can’t be part of a healthy lifestyle.

Summary: IIFYM allows you to manipulate your body composition eating foods you like. Some people abuse that freedom by eating too much junk food or developing an unhealthy obsession with planning, tracking, and preparing unappetizing yet “macro-friendly” meals, but such behaviors aren’t encouraged by IIFYM.

Using IIFYM to “Eat Junk and Get Shredded” Is Stupid 



As you know, what you eat is of secondary importance when we’re talking body composition.

The reality is the carbs in a Twinkie ultimately turn into glucose and glycogen just like the carbs in broccoli, the protein in a Five Guys burger contains the same amino acids as the protein in wild-caught fish, and the fat in an Oreo Blizzard is digested and absorbed in more or less the same way as the fat in a grass-fed, organic steak.

And so, if you hit your macros every day, you can eat any or all of these foods regularly and lose fat or build muscle. 

That doesn’t mean all foods are equally conducive to health and well-being, however. Just because you can eat a box of Pop Tarts every day and lose weight doesn’t mean you should.

Remember that food is more than a mere source of protein, carbohydrate, and fat—it’s also our source of vital micronutrients (vitamins and minerals) that support our body’s many physiological functions.

A major problem with candy and other sugary treats, overly processed foods, fast food, and so forth is they’re deficient in micronutrients. Similarly, a major benefit of eating “clean” is it provides your body with an abundance of micronutrients.

We only have so many calories we can eat every day, and if too many of them come from junk food (and thereby too few of them from nutritious foods), we can develop vitamin and mineral deficiencies that can cause many different health problems.

But that’s beyond the horizon for many people, and especially those who are enjoying the near invincibility that comes with youth. While their dietary misdeeds will catch up with them one day, that’s a problem for Future Them to contend with, not Present Them.

What they don’t realize, however, is a crappy diet can and will catch up with you long before you start receiving Social Security checks.

For example . . .

  • Research shows a high intake of highly processed carbs and sugars is associated with an increased risk of various types of chronic disease. 
  • Eating too much low-quality, processed meat may increase the risk of cancer.
  • The more trans fats (found in many processed foods) we eat, the higher our risk of heart disease, diabetes, infertility, and more.

Remember: Being jacked loses its luster if your hormones are whacked, your immune system is defective, and your body is starving for nutrients.

Furthermore, while you don’t need to eat a high-quality diet to lose fat and gain muscle, it makes it many times easier.

For instance, a diet deficient in various micronutrients can make it more difficult to lose fat.

Take zinc, which is one of the most commonly reported nutrient deficiencies among bodybuilders and required in adequate amounts for optimal thyroid function. As thyroid hormone heavily influences metabolic rate, when levels drop, weight loss can slow.

A good example of this comes from a case study conducted by scientists at the University of Massachusetts. 

Researchers took two, zinc-deficient college women and gave them 26 mg of zinc per day for 4 months. They also took careful measurements of the women’s resting metabolic rate (RMR) and zinc and thyroid hormone levels at the beginning of the study and after two and four months of supplementing daily.

Within four months, the women’s RMRs increased by 194 and 527 calories per day, respectively. Yes, per day.

That’s the energy equivalent of about 30 and 60 minutes of moderate to intense cardio, or put differently, an increase of about ½ and 1 pound of fat loss per week—purely from correcting a zinc deficiency caused by a poor diet. 

Now, these women could’ve lost plenty of fat and stayed lean without correcting their zinc deficiencies, but as you can imagine, it would be far easier with adequate zinc in their diets, which can be obtained from foods like meat, shellfish, and beans.

Another body composition benefit to eating mostly whole, minimally processed foods is they produce a higher Thermic Effect of Food (TEF), meaning the body burns more calories digesting them than it does highly processed foods. 

For example, whole grain bread with cheddar cheese has a TEF of around 20%, meaning that about 20% of the calories in the food are burned during digestion. So, if the food contains, let’s say, 200 calories, about 40 are automatically burned thanks to TEF.

On the other hand, a slice of white bread with processed cheese has a TEF of only 11%, so 200 of these calories only “cost” about 20 to process.

While a difference of 20 calories in a single meal isn’t going to impact anything, such discrepancies can add up meal after meal, day after day. 

If you’re getting, let’s say, half of your calories from highly processed, low-TEF foods, you might be able to burn several hundred more calories per day by swapping most of them for less processed foods.

Summary: You can use IIFYM to eat junk and get shredded, but this is a surefire way to increase your risk of disease and dysfunction. Additionally, it’s going to be significantly easier to lose fat and gain muscle if you get most of your calories from whole, nutritious, minimally processed foods.

The Proper Way to Use IIFYM Principles


The best way to use the principles of IIFYM, or flexible dieting as I prefer to call it, are as follows:

Get at least 80% of your daily calories from healthy (minimally processed and nutritious) foods that you actually like.

One of the biggest problems people run into when dieting is they get to a point where they just can’t stomach chicken and steamed veggies anymore, and one taste of something savory leads to an all-out binge.

Well, the best way to avoid this is to simply eat healthy foods that you like every day by working them into your meal plan as desired.

Who says you need to eat nothing but chicken? Have some steak, too! Love you some pasta? Swap out your rice and oatmeal a couple days per week! Want a delicious, high-protein afternoon snack? Skyr ( > Greek yogurt) with fruit and nuts is my go-to.

“But wait,” I can hear some people thinking, “you’re telling me pasta is ‘healthy’?”

Well, while something like white pasta isn’t the most nutritious (“healthy”) food per se, it can be part of a perfectly healthy diet. The same goes for many other foods commonly labeled as “bad,” like . . . 

  • Hamburgers
  • White rice
  • Pancakes
  • Jam, peanut butter, and mayonnaise
  • Whole-grain (or white) bread 

If you want to learn more about how to eat a healthy diet, read this article: 

How to Eat Healthy and Actually Enjoy It (Really!)

Oh and if you’re worried that eating healthy foods is too expensive, check out my article on eating healthy foods on a budget. It will help you balance not just your diet but your spending, too.

Create a meal plan you can stick to.

A major pitfall of IIFYM is taking your meals as they come, without any planning or preparation.

This leads to all kinds of wasted time and energy deliberating over what to eat next, and often a few headaches (and stomachaches) when you realize you’ve miscalculated and left yourself with too few calories to comfortably make it through the rest of the day.

I don’t know about you, but I prefer to spend as little time as possible thinking about what I’m going to eat every day. I also want consistent, rapid results, and thus, I’m a big proponent of creating a meal plan and following it every day. 

If you want to learn how to do this, read this article: 

How to Make Meal Plans That Work For Any Diet

Make room for treats.

So long as the majority of your calories come from nutritious foods, feel free to enjoy treats in moderation.

For instance, I really like dark chocolate so I eat 100 to 200 calories’ worth of it every day. If ice cream were my thing, I could do the same or maybe have it only once or twice per week but eat more in each sitting by reducing my intake of other carbs and fats for the day to make room. Pizza could work the same way.

Make your meal timing work for you.

If the nutritious foods you like to eat most tend to be high in calories (usually due to a high fat content), an easy way to accommodate this is reducing your meal frequency.

This allows you to increase the size of your meals while still hitting your calorie and macro targets.

Contrary to longstanding myths, eating fewer or more meals isn’t going to meaningfully impact your fat loss or muscle gain. 

You metabolism doesn’t slow down if you eat three meals per day versus seven and you don’t have to eat protein every 2 to 3 hours to avoid muscle loss.

Thus, you should eat on a schedule that best suits your preferences and lifestyle. So long as you hit your daily macro numbers, doing it in four meals instead of eight, or vice versa, is totally fine.

That said, it’s worth noting that a post-workout meal is likely a good idea if you’re trying to gain muscle and strength. 

Check out this article to learn why:

This Is Everything You Need to Know About Post-Workout Nutrition

In terms of pre-workout nutrition, you can either train fed or fasted and both have benefits and drawbacks.

If you want to learn more about pre-workout nutrition, read this article: 

Everything You Need to Know About Pre-Workout Nutrition

Examples of IIFYM Diet Plans

If you’re having trouble wrapping your wits around how to turn all this into workable diet plans, I’ve got you covered.

Here are eight examples of flexible dieting plans we’ve created for people as a part of our custom meal plan service:

As you can see, our clients eat a variety of foods they like and on a schedule that works best for them, which makes their diets enjoyable and easy to stick to. 

And when it comes to long-term results, compliance is the name of the game, so with our help, they have a huge headstart on building the body of their dreams.

And if you want to see the results of these types of meal plans, check out our Success Stories

Trust me—IIFYM, the way I’ve laid it out here, works for everyone, every time, without fail.

The Bottom Line on the IIFYM Diet



“If It Fits Your Macros” (IIFYM) is a dietary strategy that revolves around eating a certain number of calories and amount of protein, fat, and carbs daily from whatever foods you want.

Simply put, it’s the simplest and most effective way to control your body weight and improve your body composition.

IIFYM is synonymous with another dietary method known as “flexible dieting,” which also involves eating foods you enjoy while hitting your calorie and macronutrient targets.

That said, in practice, IIFYM tends to focus solely on calories and macros whereas flexible dieting includes other principles and methods to make dieting more enjoyable, sustainable, and effective.

A major component of flexible dieting as I teach it is an emphasis on eating plenty of minimally processed, nutritious foods, because while you can get lean and muscular eating copious amounts of junk food, it’s bad for your long-term health.

Moreover, the nutritional quality of your diet does impact how easily you can lose fat and gain muscle.

So, to use IIFYM/flexible dieting principles properly, follow these four steps: 

  1. Get at least 80% of your daily calories from healthy (minimally processed and nutritious) foods that you actually like.
  2. Create a meal plan you can stick to.
  3. Make room for treats.
  4. Make your meal timing work for you.

Follow those steps, and I promise you’ll be happy with the results. 

(Oh, and if you need a hand with implementing any of this, we can help and we guarantee results or you get your money back.)

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What’s your take on IIFYM? Have anything else to share? Let me know in the comments below!

+ Scientific References