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Lifestyle

Here’s Why The IIFYM Diet Is Dangerous, According to A Registered Dietitian

I have a bone to pick with social media and its promotion of “flexible dieting,” better known as “IIFYM.” IIFYM is short for “If it fits your Macros.” “Macros” is short for macronutrients, and refers to protein, carbohydrates, and fat. 

IIFYM is a diet where you consume a specific amount of each macronutrient per day within your caloric limitation. This differs from most diets, in that those who follow do not have food restrictions or must-eat foods. In fact, there are no dietary rules you have to adhere to, or even a structure to be followed throughout the day.

iifym chocolate candy
Caitlin Shoemaker

Let me give you an example to best illustrate. Last week, I got a call from a new client. Let’s call her Sarah. Sarah is 16-year-old high school student with a history of a restrictive eating disorder (ED) characterized by extreme weight loss with binging and purging. When she told me about her ED, she told me that in just a few months she had beat it, and was now at what the doctors considered to be a healthy weight, and was eating foods she would have never normally eaten. I was intrigued, as I know eating disorders of any nature are difficult to defeat, and wanted to hear how she did it.

As our conversation continued, Sarah explained that she was able to beat her ED because of flexible dieting. I learned that Sarah really was incorporating foods she previously swore off back into her diet (kudos to IIFYM), but she was still struggling with the obsessive, mental aspect of an ED. She was constantly counting what she ate, measuring portions, felt misery around food, and was unable to identify her own hunger and satiety cues. She had not seen or worked with a dietitian and did not receive any mental or physical medical advice before beginning this new regimen.

bmi cake
Nancy Chen

Instead, she had paid a fitness professional she found on Instagram to provide her with a macronutrient distribution. I felt a deep pain of worry upon first hearing this, but decided to hear a bit more about her diet to see if, at least, the macronutrient distribution was appropriate for someone like Sarah. Sarah was hitting her macronutrients to a tee each day — eating more when she had “macronutrients left over,” or less “when she hit her macronutrients” but was still hungry.

To no surprise, the macronutrient distribution was a complete misfit for Sarah given her age, sex, and physical activity, and actually could have led to serious negative irreversible health effects. The fat intake was frighteningly low, and the protein intake was close to triple the amount Sarah actually needed.

immortal nut meat
Kendra Valkema

What’s the danger in this you ask? Well, to start, the body can only process a certain amount of protein per time and per day. All excess must be filtered and excreted by the kidneys, placing a ton of excess stress on the organs that can (over time) lead to decreased function. Not to mention that Sarah is still growing, and in need of dietary fat for proper cognitive function during school, and possibly more importantly for growth.

There is a large unaddressed problem that people with no qualifications or health background can give improper dietary advice to strangers (including to minors) with no punishment. As a registered dietitian, I find this infuriating. It is unjust, immoral, and downright disgusting to provide dietary advice to extremely delicate and impressionable minds without proper training or credentials. The fitness professional was ripped out of her mind, with abs every girl from Australia to the United States dreams of, but that does not give her the right, nor mean she has the education to provide dietary recommendations to anyone. This, in my opinion, is medical neglect.

Study snacks Exercising working out
Denise Uy

I have continued to work with Sarah. For now, we are adjusting her macronutrient level to a safe and appropriate amount. Sarah and I will continue to work together to move her away from IIFYM, as we both agree that counting macronutrients, and everything you consume, is not an enjoyable or sustainable way of life, and is in itself considered to be a disguised form of disordered eating.

I urge everyone to second guess the health information they receive on social media, and seek the advice of professionals before starting a new regimen.