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  • Writer's pictureDr Susan Baxter

IIFYM (If it Fits Your Macros)

Updated: Feb 28, 2023

QU: Suz what is IIFYM?

ANS: IIFYM or 'if it fits your macros' is (as I understand) a type of flexible dieting and eating. It is flexible in that it acknowledges that dieting cannot be strict and work 100% of the time in day to day life. Life happens. So what it does (in a rough sense) is let you think that using portion control and ensuring that you have hit the target of your macros (your carbs and protein for which each g is 4 calories and fat for which is g is 9 calories) and you fiber requirements, that you are all set.

This works well in the real world* and has proven adherence, not to mention is a little more enjoyable for some than restricting the person to only certain food groups that they have been prescribed on a diet plan. In fact, each day you have a calories bank account and pretty much at the start of the day nothing (including cake) is necessarily off limits. However, following the plan properly (and hitting your fiber requirements) would of course mean that later on in the day you might be more reduced and limited with options such as a lot of kale and tuna to counterbalance the extra glucose and carbs in the cake.

I have used a * here because it actually depends on your own ability to be able to track your macros and know enough or be willing to learn enough about your consumption that you can be left to rule the roost. But once you are set with this, you become quite proficient and better learned about what you are eating and long term you know more about how you should eat for life. For me, I am actually quite good at eyeballing portion sizes, and therefore it isn't too tough (added to my own nutritional knowledge). However, it can be quite overwhelming for people, and sometimes can be just as strict and in fact more meticulous than just following a meal plan. It also means that whilst you can eat out more with friends, you might have to ask a lot of questions to find out what’s really in your food (is that a bad thing? maybe not).

It also has the psychological benefit that nothing is off limits, nothing is 'bad'... which means that adherence and appraisal of this kind of diet is quite high! The studies and research show that this is what matters in diet, not what the diet is, but adherence long term.

I certainly am flexible in what I eat (although I actually prefer to get my energy from wholefood sources, so sugar and cake is less appealing to me). I become stricter on my food groups coming up to a show, but that is because i tend to believe that there is still too much evidence that contradicts that all calories are created equally, and i think that my body looks best without the addition of processed food in the lead up to a show. My opinion is that if it works for you, then go hard.... this is one of those diets that can be done long term so it gets a thumbs up from me :)

For more topics on diets and dieting, read these posts: If you're wondering why the scale didn't go down click here, if you're having doubts about whether you can afford consistent exercise and dieting click here, and finally, if you're curious about high protein diets click here.

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