Introduction: Manage Your Weight Using IIFYM

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In my previous Instructable, I explained an age-old method for losing weight called intermittent fasting, many viewers were happy to try it out, others who have already been on it commented about their success ,and some were not too happy about the fact that they will have to skip meals.

So, I decided to write another weight management method , where one would not have to skip meals to get results :).

This one is Called IIFYM.

Step 1: Disclaimer

I will not be mentioning any food brands, companies names or anything of such sort, because I don't want anyone to think I'm advertising anything..This isn't the case at all. I just write these Instructables out of willingness to help out other people :).
Call it weird but it makes me feel good so I do it.

I welcome constructive feedback very good, but if you just want to type a grumpy comment, then keep it to yourself ;).

Step 2: What Is IIFYM?

IIFYM stands for If It Fits Your Macros.

Macros is short for macro-nutrients, which in this context refers to protein, fat and carbs, elements found in food.

What they really mean by that, is that when you follow this method, You may consume anything you want, if it has a place in the amount of daily macros you set for yourself.

A simple way I can put this, is that IIFYM is a weight management method that converts your food intake, and sport activities into numbers, then adds them together in a log ( food intake as +, sport activities and bodily functions as - ), with as objective to reach a certain total everyday, without going over or under it too often.

Let's call that total X.

To use IIFYM, You need to do the following:

1- Calculate X.

2-Convert it to Macros.

3-Build your Meal log based on the quantities you got.

I will explain these in detail in the following steps.

Step 3: The Pros and Cons of IIFYM

IIFYM has many advantages, but also some drawbacks.

Pros :

1-It's a very good method to follow up on the composition of your food intake, a very important factor when putting on weight, as the composition of the food you consume will determine what kind of weight you' ll be putting on, eventually reflecting on your future shape and form.

2-Bodybuilders in general rely heavily on this method when putting on weight, as it makes sure they put on more muscle than fat in the process.

3-When losing weight, it also helps you monitor your carbohydrate and fat intake efficiently, so that you can lose a lot more fat than muscle in the process.

Cons :

1- Since this method relies on weighing your food and logging food intake and sports activities, it can be very time consuming and unpractical, at least at the beginning.
Luckily, many companies have developed free apps, where you can easily log your inputs, without having to do too much Googling or copy-pasting nutritional data on spreadsheets.

2- Since all your daily food intake has to go in the log, you need to make smart food choices to be able to finish the day with a full stomache.
In a way, this method doesn't really work well for a sweet tooth, for example, as a Mars bar or a Cola are more or less around 300 calories each, they'll occupy a big chunk of the daily food intake one can consume without going over the limit.

3-in social events like going to a bar or having dinner with friends,it s not gonna be easy to log what you eat or drink.

4-Every time you want to change your food selection, You 'll to have to run the numbers all over again, but that gets easier with time.

Step 4: Calculate X, Your Daily Calorie Intake.

X will be different, depending on your weight goals.

To calculate X, simply Google "calorie calculator", and use a site that the search engine spits out.

For this Instructable, I will be using

The information you need to fill in is :

• Your age.
• Gender.
• Height.
• Weight.
• Activity.

For "Activity", simply choose "Sedentary - Little or no exercise" and hit "Calculate".

The reason I selected "Sedentary", is that websites don't really know what kind of exercise you will be doing, they just estimate how many calories you will be burning per week, and use that number in their calculations.

when I started using IIFYM back in 2012, I used one of the other options, I think it was "moderate", It gave me a bigger number than with the sedentary option, as a result, it turned out it was a bit too high for me , and my weight didn't change at all..

I personally recommend selecting the values for losing 0.5kg ( 1lb ) per week, and for gaining weight, around 0.25 kg ( 0.5 lb ) per week (if not available, divide the values to get the correct number).

Based on my experience, these are the most optimal results, but you are free to chose whatever value you are comfortable with.

Once You get X, Log it in your spreadsheet or App ( some apps do it automatically based on sign-up information, in this case, don't forget to update your weight from time to time).

A special note for the "experts" in the comment section:

I'd like to point out that at some point of one's weight loss journey, the calculator will eventually spit out a number that is inferior to one's BMR, here a lot of you are going to be saying that it's dangerous to consume less than the BMR, others will say that the body will cannibalize its organs, and other BS like you should still consume more than the BMR but Burn it... I can assure you, I've been consuming less than my BMR for over a year now, If that were true, I would be dead and buried by now.. The simple logical reason why consuming less than your BMR is not a big deal, is that YOU HAVE FAT RESERVES, that are there as a safety measure specifically for this case.

I don't want to hear about this in the comment section..

Step 5: Translate X Into Daily Macros

Now that you got the X result from the calculator, You can translate that number into Macros, to get an idea on what to eat, and how much.

For that, You 'll need to apply a nutrition school, that will depend on your weight goal ( going up?, or down?).

For losing weight, I recommend ( but not obligatory ), a Low Carb, High protein, and Average Fat diet.

In Percentages, I like to use 20% Carbs, 50% protein, and 30% fat.

For gaining weight, I recommend a High Carb, Average Protein, and Low fat diet.

In Percentages, I like to use 50% carbs, 35% protein , and 15% fat.

Again, if you are comfortable with other values, or disagree on these one, please feel free to use any values you like. After all, each person is unique and has a different metabolism speed, leading to different results with the same food intake as another person.

Another way for doing this, is to build your macro composition around your daily protein intake.

You can calculate your daily protein intake using an online calculator like this one, then adapt the other Macros ratios accordingly.

I also attached an excel macro calculator to make this easier.

Step 6: Build Your Meal Log

Now that you have the macros ratios, you are ready to build your meal log.

here you have 3 options:

1- You can eat whatever you like, and log the quantities and nutritional data in your app, keeping an eye on when you reach the limits and respecting the macro intake.

The positive side for this, is that there's no routine, you are free to consume anything you like.

The downside is that it's a bit hard to respect the macro ratios, and there's always the possibility to hit the calorie limit before the end of the day.

2- Build a one-day meals list that you consume everyday , or 7 meal lists for each day of the week, log them in once and update it from time to time when you notice weight changes on your scale.

The positive side for this is that You only do this calculations around once every 2-4 weeks.

The down side, is that you will be committing yourself to a non flexible diet, which is needless to say, unpractical if you have a social life, and will eventually become boring.

3- Use a combination of the 2 methods, simply by setting aside 200 calories a day of your Carbohydrate macros for snacking, before you build your list.

This way, You 'll have your stable meal list, but in addition, a 200 calorie carbohydrate-full snack that you can enjoy everyday.

This will make the whole project much more fun, and you 'll still be making good progress.

To build your log, simply log in what kind of food you want to eat and their quantities in a spreadsheet, and look up their nutritional data and put it in.

keep adding food until the total sum of their calories equals X.

For example:

If you decide to add say a 100 grams of Ham , it has :

Calories: 107

Carbs: 1

Protein: 19

Fat: 3

Saturated fat: 1

I uploaded a screenshot of how a meal log would look like to give you an idea. This is not a log I'm following, it's just an example.

I also attached a file containing a list of nutritional data for common foods to save you some Googling.

Side note :

I Suggest you improve your food selection, since this will play a very important role after you reach your weight goal, especially when losing weight. not many people want to stay on this method all their lives; by improving the food selection, You remove the reason you got fat in the first place.

For more info on healthy nutrition, I recommend looking up the Paleo food list.

It's basically a selection of whole foods, that aren't manufactured or tampered with by the food companies.

That will guide you on eating healthy.

Step 7: Track Your Progress

  1. Take some photos of yourself , frontal, and sides, on day Zero, and take your measurements using a tape measure.

The circumferences of the areas to measure are:





Waist line.




2. Weigh yourself.

Log the info in a separate spreadsheet or app, and repeat every month.

When you see a weight change, recalculate X and adapt your macros.

Repeat until you reach your goal weight.

Once done, Recalculate X , but this time use the "Weight Maintenance" option, and adapt your log accordingly.


Step 8: Troubleshooting

1. Your weight is not changing

Your carbs macros need to be adapted. if you are losing weight, remove 20 grams of your daily intake and try again.

If you are going up in weight, then add 20 grams of carbs and try again.

2. You 're gaining fat

Your carbs are too high or you are taking in too much saturated fats. Double-check your diet. if Fat is good then remove 20 grams carbs and try again. repeat until satisfied.

3. You're losing muscle

Increase Protein intake by 20 grams. Repeat until satisfied.

4. You find this diet too demanding.

Cook for many days at once.

5. This method is interfering with your social life:

Get picky with the food selection when you are out with your friends. Don't eat what you don't need. Drink sparkly water instead of alcohol.

6. This method is simply not for me, Do you have other solutions for losing weight?

Yes, please see My instructable about intermittent Fasting.

I'll add more cases if some come up in the comment section.

Step 9: Final Thoughts

When putting on weight

It works like magic and it is a very generous and relaxing way of eating for bodybuilders. It takes care of our food needs and gives us a beautifully set food routine, so that we don't have to worry about what we are going to eat next.

We run the numbers, cook for the whole week on Sunday, and We're good to go :).

When losing weight

This method also works for losing weight, and it has good results. I was on it for around 3 month in 2012, and I remember I lost around 3-4 kg (6.6 to 8.8 pounds).

One thing to keep in mind though is to really improve your food selection, because when people who don't eat healthy tend to go off it when their reach their weight goals, they usually bounce right back up..

My overall feeling about this method

I think it's a very good method, It has shown very good results, it's a bit demanding though, full of numbers and calculations, could be a bit of a no-no for some people.

That's it for now, I hope you enjoyed this Instructable, and found it useful.

If you have any thoughts/questions/feedback, please leave a comment and I will reply as soon as possible.