She essentially explained that if your recommended daily intake (RDA) is 2,000 calories, and you consume only 1,500 calories within a 6-hour window, you’d lose about 1 to 1.5 pounds per week. I agreed with her up to that point. However, she then claimed that it doesn’t matter what you eat—whether it’s Nutella, sweets, or fried food—you’d still be fine. At that point, I interrupted and explained that dieting doesn’t work that way. Even if you’re eating under maintenance calories, consuming the first 400-500 calories from high-glycemic foods could trigger an insulin spike. This would activate the GLUT4 transport protein along side insulin, leading the body into fat storage mode i also explained to her how insulin inhibits the breakdown of fat through lipolysis. She countered by saying that even with a large insulin surge, the body would release counter-regulatory hormones like glucagon and epinephrine to balance out the insulin levels. I agreed with that, but clarified that this response is more pronounced in people who are fit. While it might work for overweight individuals, the effect on those who are not fit won’t be as noticeable. She insisted that regardless of fitness level, if someone sticks to being 500 calories under their RDA, they will continue to lose weight, regardless of the quality of the food they eat.
Cool story
I’m not convinced that only calories are part of the concept of being healthy.
A cool experiment would be to evenly spread out cool whip calories ONLY, over the day, 500 calories under RDA - And see how you feel after a month. But maybe this one sided approach is not allowed according to the IIFYM rules?
Pretty sure Alan Aragon was the one that had someone run an experiment consuming nothing but protein powder, ice cream and alcohol to meet their macros for a month and they weren’t able to last, haha. We can’t outsmart this.
This is always the strangest argument to me. Is this an actual registered dietician you “educated”?
It is simply mathematically correct to say if you consume fewer calories than you burn, you will lose weight. I don’t understand how that can be disputed.
I agree justifying junk food is not going to be the best way to improve your health markers, but we’ve seen time and again that BMI is a significant independent driver of markers and outcomes. If you lose 30lbs eating twinkies, you will, in all likelihood, improve your health vs not losing those 30lbs.
Now we do get to, why does it matter?
Macro composition does matter, because it actually changes the calories out side of the equation. I don’t know that we have to go deep into that, because the title of this thread was about fitting your macros (not just your calories).
I agree around hormonal milieu, etc., but that stuff does get overblown and can always be overcome by lowering calories further. The question then becomes sustainability, as noted above.
Once calories get low enough, you simply can’t fit the ice cream and booze and still hit your targets… not to mention you’ll feel awful all the time.
So, all that monologue out there, I don’t see why it’s one or the other:
- Calories drive weight loss/ gain
- Macros drive composition
- Food quality drives satiety and sustainability
Whichever route you try to take will inevitably lead you to the same place. What I mean by that is, let’s say you start just tracking your macros. Eventually you’ll find you feel better and can eat more (or just simply run out of daily caloric budget) by improving your food quality as well. For example, I like having folks count their calories because I think it immediately puts that Pop-Tart into perspective.
On the other hand, let’s say you only focus on eating whole, unprocessed foods. Eventually you’ll find you feel and perform better by adjusting your plate toward a more optimal macro composition. I’ve seen plenty of young women thinking they want to be vegetarian find they get stronger and look better when they start eating chicken, and they never had to count a calorie to get there.
Super long way of saying we’ll all find our way to Rome.
You know what I do in conversation with medical professionals?
I say “Wow. Thats a really amazing way to reach out and help a great many people.”. Then I express genuine interest in their response.
They seem to really like that.
They even send me cards with hearts on them & stuff.
I dunno: signing the card of a cardiac patient with a heart seems like taunting…
At least they didn’t sign it "We hope you get this in time. 
".
IIFYM is a really low-IQ amateur-hour approach. forgive my pretentiousness. this is the kinda approach i had as a teenager (which is more doable as a very young guy compared to my current 42-year-old self).
what’s better?
a more layered/nuanced perspective and understanding of nutrition and appetite. an elemental aspect of this is understanding how different types of foods – even when equalizing for calories – have very different impacts on satiety/appetite.
summary idea: what you eat largely determines how much you eat; OR, food selections determine caloric quantity (and macronutrient distribution).
While I don’t disagree at all, this is actually why I think IIFYM is a great tool/ approach: controlling my macros will drive me to higher-quality foods.
Sure, one can argue that “nope, you’ll make ice cream fit your macros.” Which is fair, but I’d respond this is all in context to performance or body composition concerns: you’ll find you eventually either can’t fit ice cream or you don’t feel great.
The same argument can be made for the food quality approach: I find carrots are nutrient-dense, so I eat a diet wholly made of carrots, and things don’t work out so well. Again, having some awareness of my performance and body composition will take care of this.
It’s always going to come down that the answer has to be both, and we end up leading with the approach that makes the most sense for us.
To discredit myself completely on the above: I’ve gotten to where I’ll only eat grass fed beef, etc, because I believe it’s better for me across the board. I do think I can tell a performance/ body composition difference over the long run, but not in an acute enough manner a complete IIFYM approach would have led me here; I did have to make a pure food quality choice after doing some reading.
100% agree
Calories are a convenient way to describe energy. But your body does not dismantle foods using complete combustion the way a calorimeter might.
IIFYM is great if you want to justify whatever crap you are eating. The reason it is hard to lose weight is that your metabolism adjusts to whatever diet you throw at it. This does not mean calories in and out isn’t important. Just that the actual weight change will be less, sometimes much less, than what theory implies.
Your mother was right. Some foods are obviously healthier than others. Eating sugar may provide energy but it might not be optimal in terms of mitochondrial health, preventing chronic disease, or improving the gut microbiome. If you eat mainly healthy foods with adequate fiber, counting calories becomes a lot less important.
I know a lot of nutritionists. None of the ones I know recommend eating whatever you want (as long as there is a calorie deficit). Accordingly, I am slightly skeptical of this story, which could be missing at least one important detail.
I find this to also be the case if you eat healthy foods with no fiber, haha.
I feel like one of the biggest issues with the dialog is we keep thinking we all mean the same thing when we say the same words, but we don’t. The discussion is about “weight loss”, but when most people say “weight loss”, they WANT to mean “fat loss”, and that’s where nuance comes into play. CICO is 100% correct: if your caloric intake is under your caloric output, you WILL lose weight. It’s also self-referential: if you’re not losing weight, by definition, your caloric intake is exceeding your caloric output.
However, caloric output can be manipulated through a variety of factors, hormonal and otherwise, AND “weight” can also be comprised of fatty and NONfatty tissue. Most people saying “I want to lose weight” do NOT mean “I want to keep all my fat and lose as much muscle as possible”, but that’s AN outcome that can occur if we’re concerned purely with CICO.
And along with all this, other extreme examples abound. The fastest way to lose weight is via amputation. Another quick water is through water cutting. And in those instances, CICO was WRONG: I lost weight WITHOUT having to be in a caloric deficit!
Ultimately, we all end up talking past each other, strawmanning the other side and confusing the hell out of anyone that is listening to us.
Insulin management will make body composition goals much easier as long as protein is sufficient. CICO and IIFYM are just acronyms that leads people to think you know something about diets.