IIFYM: Flexible Dieting–If It Fits Your Macros

You may have already heard about the latest nutrition trend – If It Fits Your Macros or IIFYM. You may even associate it with countless photos of donuts and burgers on Instagram. But what is IIFYM all about?

What is IIFYM?

Simply put, IIFYM or flexible dieting is just a balanced approach to nutrition. Basically, the concept is to establish the amount of calories you should consume daily, depending on your goals and lifestyle. Then, you calculate the ratio of macronutrients (protein, fat and carbs) that should make up your calories. This can be done using many formulas and calculators available online and will, once again, vary from one person to another. It doesn’t matter if you want to lose fat, put on muscle or maintain your current body composition; IIFYM is an individual approach so it works for everyone.

Once you have your four essential numbers (calories, protein, fats and carbs) you should find a tracking app or website that will allow you to log and count your daily intake. Then, all you have to do is to plan at least a day ahead to make sure what you eat fits into your macro allowance for the day.

How Flexible Dieting Works

An advocate of the Flexible Approach, a coach and researcher Alan Aragon says that it is unreasonable to label foods ‘clean’ or ‘dirty’, especially given how the idea of what is healthy has changed throughout time. For example, in the 80s all fat was considered evil but in the 2000s we started leaning towards consuming fat in moderate amounts and some diets even glorify it as a miraculous cure for almost every known disease (the bulletproof diet, the keto diet). Also, Alan points out, that judging processed foods as ‘bad’ may be an overstatement. Most health and fitness supplements are highly processed yet considered beneficial to our health (for example, vitamin or protein supplements).

The IIFYM approach is based upon the fact that the first and most important factor in weight loss or gain is the number of calories consumed. Even the macronutrient ratio is of secondary significance when it comes to weight loss alone. Health is a different matter but we will come back to that later.

Surwit and colleagues compared the 6-week outcome of 2 diets – both in caloric deficit, with 43% of total calories as sugar vs. 4% of the total calories coming from sugar. They observed no major difference in the result when it comes to weight loss and fat loss and the health stats were also similar for both groups. To conclude, overeating is the biggest factor in both obesity and health risks associated with it. But what about counting the macros, then?

The proportion is important if you want to change your body composition (i.e. higher protein for muscle building) and achieve optimal health. As much as ‘a carb is carb’ you will want to limit your sugar intake in order to maximize the nutritional value of your foods (including carbs). You will need variety if you want to provide your body with precious vitamins, minerals and fiber.

Does Flexible Dieting=Eating Donuts All Day?

Flexible dieting is not an excuse to eat unhealthy foods. But, based on the concept of ‘everything in moderation’, if you can fit a donut or burger into your meal plan so that it is in line with your macros, by all means do so. If done properly, IIFYM will not allow you to eat junk all the time. For example, a few donuts can take up all your fat allowance for the day. This means you can’t eat another gram of fat that day, which will be tricky since even chicken, lean meats and low-fat dairy contain traces of fat. So BAM! – you eat donuts all day – you’re not going to hit your macros.

If you adhere to the 80/20 rule – 80 percent whole, organic ‘healthy’ foods and 20 percent ‘cheat’ foods that fit your macros, you are most likely to remain healthy and hit your fitness goals. It is not uncommon that fitness and figure competitors use this method to prep for a contest. You just need to track your food accurately and believe me – you will be able to eat whatever you want (in moderation).

Benefits of IIFYM

Labeling foods ‘bad’ or ‘dirty’ and excluding them completely from your menu will make you feel restricted and more likely to binge or even develop an eating disorder. Some people develop an unhealthy obsession with healthy eating called Orthorexia Nervosa which can lead to constant anxiety over food and isolation from others. Flexible dieting enables you to plan what you’re going to eat and fit it into your daily intake so you can participate in social activities and eat out if you want to. Trying everything allows you to observe your body and make necessary adjustments. Also, you can simply enjoy your food!

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Aragon, A. The Dirt on Clean Eating http://wannabebig.com/diet-and-nutrition/the-dirt-on-clean-eating/

Gajda.K. What is Flexible Dieting: IIFYM Uncovered http://www.wecanbethegreatest.com/what-is-flexible-dieting-iifym-uncovered/

Kratina. K. Orthorexia Nervosa https://www.nationaleatingdisorders.org/orthorexia-nervosa

National Academy of Sports Medicine: Do Cheat Meals Make Sense? http://blog.nasm.org/nutrition/cheat-meals-make-diet-sense/

Surwit RS, et al. Metabolic and behavioral effects of a high-sucrose diet during weight loss. Am J Clin Nutr. 1997 Apr;65(4):908-15.

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