Flexible Dieting: Why You Should Try This Now

what is flexible dieting
what is flexible dieting

You’ve probably heard the phrase “flexible dieting” being bandied about or wondered what the IIFYM acronym really meant. Well, if you’re looking for a new way to lose weight and stay fit, these two might just be your thing. Flexible dieting has caught the fancy of first-time dieters and fitness veterans alike. At last count, the IIFYM website put the total number of registered dieters at several hundred thousand, inching closer to the million mark with each turn of the ticker.

But what is so special about this approach? And how is it any different from good old-fashioned calorie counting? Here is some help getting your head around the terms and concepts, apart from a closer look at how flexible this diet really is.


If It Fits Your Macros (IIFYM), Eat Everything

While the acronym IIFYM sounds suitably intimidating and unusual, once you decode the formula for flexible dieting, it will seem a lot easier.

IIFYM is short for “if it fits your macros,” the foundation of the flexible dieting phenomenon. What it means is that you track your consumption of macronutrients, and as long as your food choices fit into those targets, you can eat what you like. Of course, that is not all there is to it, which is why we will dive straight into how this really works.1


You can start with any online macro calculator to arrive at the intake ideal for you based on your vital stats and goals. Also, know your total daily energy expenditure (TDEE; calculated using your gender, height, weight, age, and level of exercise).

According to one such calculator online, in general:

  • Have 0.825 gm protein for every pound of your weight
  • Get 25% of your TDEE from fats.
  • Get the rest of the TDEE from carbohydrates.2

Use a digital food scale to be sure you are not being too generous with your “half cups” and “spoonfuls” of food and measure them to the gram. Then, set up a macro-tracking app. And lastly, be sure you are staying well hydrated.3

Flexible Dieting Allows You To Eat Your Favorite Foods

The idea behind this form of dieting is that one size does not fit all. So, depending on your own body composition, activity levels, needs, and goals, you will need to arrive at a daily target for fiber and the levels of macronutrients (fat/protein/carbs) you get through your diet. Your goals could be different from your spouse or best friend, unlike a traditional diet which would have both of you eating as per the same meal plans.


And while that is the reason it works for so many people, it is not why it is making waves. That bit is thanks to the rather flexible freedom of choice that a dieter on IIFYM has – which some claim means you could chow down on some treats now and again without worrying that you are cheating on the plan.

Tempted by your mom’s lemon meringue pie? Can’t resist a quick bagel or donut for breakfast? It is all kosher so long as it does not bust your daily target – what the creators dub as checking if it “fits your macros.”4


It’s Easier To Stick To Flexible Dieting For A Longer Time

According to one champion of flexible dieting, physique coach and pro body builder Dr. Layne Norton, who also holds a PhD in nutritional sciences, the power of this approach is that it can be applied to your eating all your life. It is not a short-term weight loss diet plan. According to Norton, while it can help you achieve some of those goals, flexible dieting enables people to stick with the program for years, as opposed to a few days before they cave.5

Instead of suddenly eating foods you cannot stand just because they are healthy, while giving up your favorites because they are less than perfect, in IIFYM you can enjoy what you eat and still work at fitness goals and staying healthy.6


According to research on flexible dieting against conventional calorie counting or conscious dieting, those who were on a flexible dieting plan tended to have lower body mass, experienced less anxiety and depression, and were less likely to overeat. On the other hand, typical dieting that restricted intake actually ended up causing subjects to overeat and resulted in increased body mass.7

Cut Back On Junk Foods Even If They Fit Your Macros

While all of this may sound fabulous on paper, do keep in mind that you cannot go completely berserk with your food choices and expect to stay in great health. You may see some weight loss as a result of macro watching, but if you choose to consistently get your carbs from refined flour and not whole grain, or pass up leafy greens for red meats, it will play out on your health too.


The flexible dieting approach gives you a tool to track yourself, but you probably should not do this in isolation, turning a blind eye to other health and fitness common sense like getting your “five a day” or avoiding refined sugars and flours.