Also referred to as IIFYM, “If It Fits Your Macros” has become increasingly popular among MyFitnessPal users, who appreciate the combination of accountability and flexibility it offers. And the MyFitnessPal app is the perfect tool to help you succeed with the IIFYM approach.

If you’ve been curious about IIFYM, this beginner’s guide will walk you through the basics and give you some tips on how to integrate it with your MyFitnessPal tracking — as well as how to maximize your success.


Macros, in this case, refers to the three primary macronutrients: fats, proteins and carbohydrates. The guiding principle (and chief selling point) of IIFYM dieting is that you can eat whatever you want and still attain your goal of losing or gaining weight as long as you stay inside your macronutrient “allowance.”

You get an allowance in grams for fat, protein and carbohydrates, but how you want to spend that allowance is up to you. If you want to spend your carb allowance on jelly beans instead of oatmeal, that’s up to you. If you want to eat pepperoni pizza instead of salmon and brown rice, that’s allowed, too. Anything goes, as long as it fits your macros.

While we know a calorie isn’t just a calorie and that your food quality matters, IIFYM may help those who feel jaded by choosing “healthy” food all the time. After all, nutrition is not one-size-fits-all. If you’re a healthy individual, it’s helpful to explore different options and find one that works for you — bonus points for making it a sustainable habit!


If you’re new to IIFYM, here are a few tips to get you started.

Step 1: Set Your Calories.

The first step is to establish your target calorie intake, based on your current weight, age, height, sex, activity levels and goals. You probably already did this when you set up your MyFitnessPal app. To view or update your Diet Profile, click on Settings and choose Update Diet/Fitness Profile.

Step 2: Set your Macros.

Next, you’ll want to determine how you’re going to divide those calories among the three macronutrients. You can view or edit your macro distribution in your MyFitnessPal app by clicking on Goals, where you’ll see your Daily Nutrition Goals.

MyFitnessPal automatically sets your macros at 50% carbs, 20% protein and 30% fat. You can tweak this distribution to your liking, and the app will translate the percentages into grams for each macronutrient. (Note: Premium app users have the option of setting goals in grams or percentages.)

Need some guidance? See this article on adjusting your macros.

Step 3: Plan and Track Your Diet.

As you enter meals and snacks into your food diary, MyFitnessPal will total up how many grams of carbohydrates, fat and protein you’ve eaten. You’ll have a better idea of what’s left for the day based on your goals. Entering your meals as you go allows you to calibrate subsequent food choices based on your remaining macros. This can get tricky especially if you get to dinnertime and realize you only have 5 grams of carbohydrates,15 grams of fat and 60 grams of protein left for the day. Needless to say, this can lead to some strange meals!

You may find that it works better to plan your entire day in advance and adjust as needed. It does take a little practice to learn which foods are good choices for certain types of macronutrients. Here are a few tips that can help:

  • High in carbs, low in protein: fruits and vegetables
  • High in carbs, low in fat: pasta, rice, cereal, bread, legumes, fruits, vegetables
  • High in fat, low in carbs: nuts, seeds, olive oil, cheese
  • High in fat, low in protein: avocado, olive oil, coconut milk
  • High in protein, low in carbs: eggs, meat, fish
  • High in protein, low in fat: nonfat Greek yogurt, cottage or cream cheese, turkey or chicken breast, lean ground beef, whey protein powder

Step 4: Repeat and Refine.

That’s pretty much it. With time, both the planning and the execution tend to get easier. Once you have a few successful IIFYM days logged in your Food Diary, you can use these as a resource.


As a nutritionist, I initially thought the IIFYM approach sounded like a horrible idea. Although it’s important to get the right quantity of macronutrients, the quality of those macronutrients matters too. While 100 grams of salmon and 100 grams of hot wings may have the same macronutrient profile (both are about 60% protein and 40% fat), I would hardly consider them equivalent nutritionally. Jelly beans and sweet potatoes are both about 100% carbohydrates, but, again, there’s no comparison when it comes to nutritional value. Could you lose weight eating nothing but hot wings and jelly beans — as long as they fit your macros? Probably. But I don’t recommend it.

Fortunately, most people doing IIFYM quickly discover that they feel much better when they spend most of their macros on fruits, vegetables, nuts, healthy fats, legumes, whole grains, lean protein and other wholesome foods, which tend to be more filling as well as more nutritious. That, plus the flexibility to indulge when you want to (as long as it fits your macros) is, for many MyFitnessPal users, a winning (and often, a losing!) proposition.

Monica Reinagel, MS, LDN is a licensed nutritionist and creator of the top-rated Nutrition Diva Podcast. Find more nutrition and diet tips and recipes at, or connect on Facebook or Twitter




  1. Molly

    When doing IIFYM go by grams, not percentages, and use MFP to make sure you’re getting all your nutrients in. Try to limit refined sugars and saturated fat as much as possible and avoid trans fats and hydrogenated oil. Try to stick to sugar from fruit. The body doesn’t process maple syrup, honey, coconut sugar or agave any different than granulated sugar; it’s still pure sugar. The only difference between fruit sugar and pure sugar (aside from fruit containing vitamins/minerals) is fruit contains fiber which reduces the spike in blood sugar a bit and the water fills you up (if you aren’t eating dried fruit). Don’t go overboard on fruit either, too much sugar, regardless of the source isn’t good. There are plenty of healthy dishes you can make with some fruit, dark/pure cocoa and stevia to satisfy a chocolate craving. You can always replace oil with mashed banana or applesauce in baked goods and if doing boiled cookies, you can replace some oil with your milk of choice. PB2, cocoa, bananas, blueberries, almond milk, dairy free protein powder, egg whites, fish, chicken and a variety of veggies are all staples in my diet. Drink plenty of water, exercise and tweak your macros if need be. If you find you’re craving protein, up your protein intake. If you find yourself constantly craving peanut butter (and aren’t dealing with heightened stress levels or near that time of the month), up the carbs and decrease the fat if doing low carb or decrease carbs and up the fat if doing low fat while keeping calories consistent. If you find your macros near impossible to stick to you can google what your specific cravings may mean and adjust accordingly but try not to go to extremes. I recently found I needed to decrease my fat a little and up my protein and now I don’t seem to be getting uncontrollable cravings despite being under a fair bit of stress at the moment. Getting your macros just right takes time and you may need to adjust at different points in time depending on your goals. Be careful about having easily accessible junk food in the house (chips, chocolate chips) and try to opt for things you would need to actually whip up so you have to think twice. If you learn some healthy treats to make and overeat regardless, it won’t be as bad as it could be. Be patient and you’ll get the hang of it! Don’t beat yourself up if you overindulge or fall off track and all the best to everyone! 🙂

  2. Charmaine Ng

    I’ve been wondering if I should start IIFYM because it certainly does help eliminate the idea of “bad” food and restricting eating habits.
    – Charmaine

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