Free Shipping Worldwide!

Flexible Dieting

Have you ever wondered if there was a way to eat whatever you want, whenever you want, and still obtain the body you want?  Of course you have, you’re human.  In this blog post we’ll go into detail about IIFYM and how you can apply it to transform your body!  Broadly, this post will cover the following:

  1. What flexible dieting / IIFYM is and how it will allow you to eat normally and still help you reach your body goals.
  2. How to calculate your macronutrient ratios and how many grams of carbs, protein, and fat you may need to consume daily in order to drop body fat.
  3. How to start tracking your macros and the best apps, calculators and tools to help you along the way.

What is IIFYM?

IIFYM (If It Fits Your Macros), also known as flexible dieting, is a nutrition system that brings healthy eating back to basics: carbs, protein and fat.  IIFYM revolves around tracking the three macronutrients (carbs, protein and fats) in all foods and adjusting your daily intake and ratios to reach your body goals.

Flexible dieting is a system of eating based on giving your body what it needs to perform and function, whether your goal is to lose fat or gain lean muscle.  Each day, you eat a specific target of macronutrients - think daily food budget!  Those macronutrients: proteins, fats and carbohydrates add up to a certain number of calories.  Stick with it… the we’ll explain the simple maths in the next section.

What are macros?

“Macros” is short for macronutrients – Carbohydrates (“Carbs”), protein and fats.  If you breakdown food, it is made up of a split of these macronutrients and your body processes each in a different way.  Each macro is a substrate that is broken down in your body and used for different processes.   Generally, macros are measured in grams (g) with an energy unit measurement conversion known as a calorie (kcal) (check out the packaging on your favourite cereal box and you’ll see what we mean!).

This is the conversion factor:

1g of carbohydrates (carbs) = 4 kcal

1g of protein = 4 kcal

1g of fat = 9 kcal

The simple maths is:

Carbohydrates + Protein + Fats = Total Calories

As we mentioned earlier, you have a daily budget of macros, and as long as you fall within this budget, you can eat whatever you want!  However, note that if you avoid fresh unprocessed foods like the plague, you are risking creating deficiencies and numerous health problems.  Healthy foods contains various micronutrients (vitamins and minerals) that are required for optimal body function.  As with everything in life, try the 80/20 rule - 80% unprocessed, whole foods and 20% treats.  This will allow you to enjoy yourself, even when you a diet.

Some examples of whole food sources for each macro is listed below (by no means an extensive list):

Protein: Chicken, eggs (specifically egg whites), steak, fish, turkey, greek yoghurt, protein powder (check the labels!) and jerky.

Carbohydrates: Rice, bread, pasta, potatoes, oatmeal, vegetables, fruit and rice cakes

Fats: Avocadoes, nuts, peanut butter, full fat dairy products, whole eggs and fatty fish

It matters much less WHAT you eat than the macro budget you take in.  It is important to get as close to your numbers as possible. Don’t fret about hitting your numbers exactly, but try to be consistent and hit within about 5g of each value.

Finding your ideal macronutrient ratio for your goals

First things first – you need to have a goal. Your goal will determine whether or not you need to increase or decrease your base daily caloric intake.  Starting with this number will then help you to determine the number of macro split you need.

Step 1 – Determining your daily intake

First step is to determine your current caloric intake.  There are two ways of doing this – first is the scientific approach, which is finding your basal metabolic rate (BMR) and your TDEE (total daily energy expenditure).  Alternatively, you can track your eating habits for a week or two and determine your current calorie intake from that.

To find your BMR first plug in your current weight, height and age into this calculator.  Next, you determine your TDEE by taking the calculated BMR and applying the relevant activity type (people generally overestimate their level of activity, so err on the lower side if you’re not sure):

Sedentary = BMR X 1.1-1.2 (little or no exercise, desk job)

Lightly active = BMR X 1.2-1.4 (light exercise/sports 1-3 days/wk)

Mod. active = BMR X 1.4-1.6 (moderate exercise/sports 3-5 days/wk)

Very active = BMR X 1.6-1.7 (intense exercise/sports 6-7 days/wk)

Extr. active = BMR X 1.7-1.9 (intense daily exercise/sports & physical job)

This total is then your estimated daily caloric intake.  If you think this number is coming out a bit low, track your food for a week or so as we suggested and start with that number (food tracker apps listed below).

Now that you have your current daily caloric intake, adjust your goal caloric intake based on your goals.  From here it’s a lot easier, if you want to lose weight, you go into a caloric deficit and if you want to gain wait, you go into a caloric surplus!

General guidelines on how much to add or subtract are here:

Losing weight: decrease 500kcal per day. This should result in a healthy 0.5-1lb loss in body weight per week.  If you find that you are losing more than that after a couple of weeks, add back 100kcal (made up of either carbs, fats or a combination of both).

Gaining weight: increase 150kcal per week – aiming for about a pound a month of weight gain. This should allow for muscle while limiting gains in body fat.  Again, if you’re not gaining, add in a bit more calories.

As a general guideline to allow for additional flexibility within the IIFYM system, the average deficit or surplus throughout a week is more important than day to day, i.e if you go over your macro budget for a day, “borrow” / subtract a small portion of your macros over the next 3-4 days to ensure that you are still hitting your weekly deficit of around 3500 calories.

Step 2 – Determining your macronutrient split

As a general guideline, you can start with the following split:

  • Protein ratio is set at 0.85 - 1 grams per pound of bodyweight.
    • Protein helps us to recover from our training, it preserves lean tissue when trying to lose weight, helps us grow more muscle when bulking up, and has the highest effect on satiety of all the macronutrients.
    • If your main mode of exercise is weightlifting, then you probably require more dietary protein than someone who focuses on endurance training.


  • Fats are set at 20-35% of daily energy expenditure.
    • Consumption of dietary fat is important for regular hormonal function in both sexes. If you drop your fat intake too low for a long period of time, the most obvious change you will notice is a decrease in sex drive. Fats should never be eliminated from a diet.
    • Your gender and starting body type can make a difference in how much or little fat you can consume in a day. The amount of fat that you naturally store can have an effect on the way that you mobilize, or utilize the stores of fat that you have.


  • Carbohydrate grams come from the remainder of your calorie intake.
    • Carbohydrates are the only macronutrient humans can live without. However, carbs still do play a major role on the human body and have several positive impacts on hormones, help us fuel our workouts, replace muscle glycogen (the primary and preferred fuel source of our muscles), and generally make adherence a whole lot easier.

Protein is the most important macronutrient when dieting, so when possible, stick to your allotted protein target.  With your fats and carbohydrates, there is some wiggle room with the ratio.  For example, if you can’t live without your peanut butter, allot more fats into your diet (i.e go up to 30-35% of your calorie intake).  On the flip side, if you love your bread and rice, lower your fats to allow for more carbohydrates.  Dieting is never fun, so why not make it as easy as possible for yourself!  What’s most important is that you are still in an overall calorie deficit / surplus.

Paired with a proper training routine and adhering to your macros, this system should support steady fat loss for at least 4-6 weeks before any adjustments are required.  Start by making minimal adjustments, i.e 100kcal of either fats or carbs.

Tracking your food with Apps

So now that you understand the basics of nutrition, it’s time to put in the work!  If you don’t already own a digital food scale, get one!  This will allow you to measure out your portion sizes and keep on top of your daily macros.  Two of the biggest Apps out there are MyFitnessPal and MyMacros+.  Both have a large database of food items that other users have input – just compare the packaging to the version you have selected!

Over time, you’ll find that you more or less stick to the same foods and menus, so logging won’t be as much of a chore.  Additionally, you’ll also learn how to start eyeballing portion sizes (not recommended for newbies!), so you won’t need to weight out all your foods.  Ultimately, this is the end goal which will allow you to eat within your means and maintain the body type you always dreamed of!

Remember, everybody’s basal metabolism and body functions are different.  It may take a few weeks of tweaking your calories and ratios to find what works optimally for your specific body.  Just remember to track your data points (i.e calories and weight), so you know how to make your adjustments.

The point of flexible dieting is to keep enjoying the foods you eat and to take away the stress of fad diets.  Give your body what it needs and wants.  When it all comes down to it, the most important thing is that you are willing to change your plans according to the situation and just go with the flow.  You missed a meal?  So be it, adjust your macros for the day.  You ate an extra serving of birthday cake?  No need to go all out and eat another 7 slices, adjust your macros for the day or the next few days even!  Don’t make dieting any harder than it needs to be!

We hope that helps and gives you starting guideline on how to implement a safe eating system into your lifestyle.

Flexible Dieting


Leave a comment

Please note, comments must be approved before they are published