The Rules of IIFYM

IIFYM: If It Fits Your Macros

IIFYM stands for If It Fits Your Macros. The concept behind it is eat clean as much as possible, but you can add in processed foods guilt-free when needed, as long as you fit in all of your macro-nutrient needs (protein, carbs, fats and fiber) for the day. Depending on your fitness goals (weight-loss or muscle building), your macro-nutrient intake will be unique. So, with IIFYM, don’t follow any specific diet plans found on the internet. These plans won’t put into account YOUR stats (weight, height, sex, age and exercise level) to achieve the best results. One of the first things you’ll want to do, no matter what your goal, is find out your BMR (basal metabolic rate). This is the number of calories you’ll need to consume daily to either lose weight, maintain your current weight or gain weight.

IIFYM is all about improving your body composition through means of adequate macro-nutrients and calories. All you have to do is stay within your allotted macros, and the fat will start falling off! IIFYM teaches you that if you eat less calories than your body requires, while simultaneously getting in your macro-nutrients, that you’ll lose weight at a steady state – regardless of if you like pizza or chicken.

Who coined this term?

A group of bodybuilders (male body builders) according to the official IIFYM website ( ). Male bodybuilders (in my opinion) don’t need to worry about calories as much as just some average Joe Shmo who works out just to stay in shape year round. Women especially, who already gain weight easier than men, WILL start to gain weight if they begin to think “it’s ok to have a candy bar or ice cream because It fits into my macro-nutrients for the day.” I’ve seen it happen with my own two eyes.

What about your micro-nutrients?

Your body’s efficiency on how well it burns fat and builds muscle is highly dependent on high micro-nutrient foods. I’m not talking about taking 1 multi-vitamin a day from a $10 bottle to fill in the gaps. I’m talking about whole, raw foods like fruits and vegetables to get your “quality” micro-nutrients. In a sense, these raw foods (fruits and vegetables) can count towards your fiber intake, which is something that’s highly recommended in the IIFYM plan. Followers of IIFYM suggest 50-60 grams of fiber a day, or 20%-25% of your body weight ( 150lb = 30-37.5 grams of fiber).

Did you know that too much fiber can cause Mal-absorbstion of some crucial vitamins and minerals?

How To Start IIFYM

  1. Find out your BMR (link above).
  2. Use the IIFYM calculator to get your exact macro-nutrient intake. Here’s the IIFYM calculator
  3. Buy a digital scale and measure everything in grams, pre-cooked.
  4. Weigh everything you eat for the first 90 days until you’re comfortable with eyeballing your food portions.
  5. Keep track of everything you consume using an app like My Fitness Pal.
  6. If your goal is to lose weight consume 15% – 20% less than your BMR number ( 20% of 2,000 calories is 1,600 calories, 15% of 2,000 calories is 1,700). I recommend subtracting 500 calories from the big number (bottom number) for best results. This will equate to a 3,500 calorie deficit each week, or one pound loss. Just don’t go below your top number, which is the number of calories your body requires to function in tip-top shape.
  7. If your goal is to gain weight consume 5% – 10% more than your (bottom) BMR number ( 10% of 2,000 calories is 2,200 calories).

If you have a fat-loss plateau lasting longer than 5 days reduce your daily intake of carbs by no more than 10 grams. Never reduce your calories or carbs if you are still making progress. The only time you should reduce your macros (carbs) is when you’re at a weight-loss plateau for more than 5 days.

General Macro-Nutrient Guidelines –

  • Consume at least 1 gram of protein for every pound of body weight (150lbs = 150 grams of protein a day) .85 – 1.25 is acceptable.
  • Consume between .35 – .50 grams of healthy fats for every pound of body weight. (150lbs = 52 – 75 grams of fat a day)
  • Consume 20% – 25% of fiber per pound of body weight (150lbs = 30 – 37.5 grams of fiber a day).
  • Any remaining calories you have left will come from carbs.
  • Drink 1 gallon of water a day.

Is IIFYM Any Different From Clean Eating?

No! This is basically what IIFYM, also known as flexible dieting, is.

You’re still:

  1. Monitoring what you eat throughout the day – same as clean eaters.
  2. Roughly counting calories – same as clean eaters.
  3. Roughly counting macro-nutrients – same as clean eaters.
  4. Choosing healthy foods to reach your macro-nutrient goals – same as clean eaters.
  5. Allowed a treat daily – same as clean eaters.

There are those though, that don’t count calories or macro-nutrients because they choose to focus on eating healthy in general, and are still in great shape. Proponents of IIFYM claim that clean eating allows for more frequent binges. Well not if you’re eating enough throughout the day and keeping your blood sugar stable. Have you  ever binged on a full stomach? Not me! Binges (in my opinion) are more psychological than anything – not entirely due to the way you choose to eat. Binges can be as a result of poor eating habits, like going too long without eating or cutting too many calories. They can also be due to trying to fill a (emotional) void that eating can satisfy, or when you get a first taste on something sweet you haven’t had in months.

I used to binge three, sometimes four times a week, for years. It had absolutely nothing to do with what I was eating (which was healthy for the most part, or “clean”), but more to do with how little I was eating, how much I was exercising and emotional triggers (such as stress, boredom, sadness, frustration, etc.). I personally believe that it doesn’t matter what diet you’re on (a clean diet or IIFYM) – if an individual has an underlying issue with food (restrictive eating, binging, bulimia, etc.) it’ll always manifest – no matter what. I also believe that you’re more likely to binge/over-eat if you’re cutting calories and “bad” foods too much, such as pizza and sweets. That’s so unrealistic!

Why I Don’t Entirely Agree With IIFYM (but why you should make your own decision 🙂 

I had a debate recently with someone who compared a donut to an apple when it comes to getting in those last 20 grams of carbs to fit into your macros. Donuts and apples!? She said, and I quote “20 gr carbs from an apple = 20 gr carbs from a donut. Your body can’t tell the difference.” YOU”VE GOT TO BE KIDDING ME!? I think this is why IIFYM can be confusing to some that don’t understand macros and the basics of nutrition. If you can find a coach that follows IIFYM and knows how to make it work for you, then I encourage you to try it out. Just don’t go into flexible dieting blindly, thinking that you can eat highly processed, low quality, high fatty and sugar laden foods and expect dramatic results in a short amount of time.

A donut has no vitamins, no minerals, is low in fiber, high in processed sugar, high in saturated fat and has no health benefits. Most likely it will only make you feel sluggish after you eat it due to the insulin spike crash you’re about to encounter five minutes later. Now an apple on the other hand has close to as many carbs and grams of sugar as a donut, BUT it has no fat, no saturated fat, no sodium, much more fiber (which will satisfy you and keep you fuller, longer), vitamins, minerals and has a million more health benefits, unlike, you guessed it, the donut. Another example of what I’ve seen (and this is what really got me researching about IIFYM), is seeing a female getting in part of her 55 grams of fat allotted for the day from a Hershey’s peppermint chocolate bar – I didn’t get it, when there are much better options to choose from.

My final thoughts

  • Choose healthy, whole foods with very few ingredients.
  • Read the Ingredients List and Nutrition Facts on everything – know what you’re putting into your body.
  • Don’t stress if you eat off whatever plan you’re following. Allow yourself a treat every so often, after you get in all of your macro-nutrients from healthy food sources.
  • Stay away from things like pop tarts, donuts and candy bars for 30 days and tell me how you feel AND look. Join my 21 Day No Sugar Challenge on Facebook – where girls were losing 2-8lbs in just one week!
  • Know your BMR and macro-nutrient uptake for reference, but don’t stress if you get too many or too few of either.
  • Research everything before you jump on board any new diet trend.
  • Nothing is better for your overall health than nutrient dense foods like fruits and vegetables.
  • Be happy and find balance in all that you do 🙂


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