Is it CICO or not?

You are not missing anything, exactly. CICO works.


As you pointed out, the closer you get to maintanance the smaller the calorie amount you can eat and stay in deficit. The problem is your body needs a certain amount of nutrients to work right, so you cannot (should not, at least) shrink your calories indefinitely to keep the deficit high. Generally recommended, and used by MFP, is a minimum intake of 1200kcal for women and 1500kcal for men to ensure you get everything you need. - That means, though, that the deficit shrinks. So you lose less weight than in the past. AND you have to be extra careful with logging to not by mistake destroy what little deficit you have. Thus, losing the last few kilos can be harder for many people than earlier loss.

"You should be eating.more." again tends to be health advice, not weight loss advice. You should be eating more than 1000kcal a day to stay healthy, even if you are losing faster with a larger deficit, for example. - Or it may just be helpful for long term loss (not getting frustrated and giving up) to eat at a low deficit if that helps you stick to it. Things like that. (Plus there seems to be some merit to "maintenance breaks" helping with Weight loss in the long run, but I cannot remember enough about that right now to make any real claims.)

So yeah, CICO works, but health is more important than large deficits and fast weight loss.

1) As you said, when you only have a few lbs to lose, your TDEE is not nearly as large as if you had a lot to lose. If you keep your exercise habits the same, your deficit is smaller, so weight comes off slower.
2) Diet fatigue and portion distortion are common toward the end of your journey. You think you’ve got your healthy habits nailed, so maybe you’re not logging every single nibble, you’re not using your food scale all the time, your cheat meal turns into two or three meals... What you’re logging doesn’t reflect what you’re really eating.
3) A too-big deficit can cause some people to become less fidgety or more lethargic, so they end up burning fewer calories than expected.
4) If you eat in a deficit for an extended time, a small amount of adaptive thermogenesis can occur, so your burned calories will be less than a calculator would expect, slowing weight loss.

As for “eat more,” having a smaller deficit when you have less to lose helps preserve muscle mass, helps keep your energy levels reasonable, and ensures you don’t end up with nutrient deficiencies.

To add to what's already been said - that last ten pounds is hard. The body does NOT like being in a calorie deficit when there isn't much body fat and will slow down every single body function to preserve energy.


Then - hunger. There is a lot of hunger in losing that last ten pounds even if you do it right. The body has a rock in its glove and will do everything possible to get you to eat when body fat percentages get low enough. Sure, some people try to hack the system and eat low cal anyway.


Such a bad idea on so many levels.

jogman wrote: »

I tend to lurk more than post but I have a serious question. I have gotten a lot of help and info from the forum over the years. However, I continue to be confused when I read responses to individuals that “you need to be eating more” or “the last 10 pounds are the hardest” or general comments that would indicate the CICO formula doesn’t work. If one is in a deficit then they should be losing according to (Total deficit calories for the week/3500 for lbs lost in a week). It shouldn’t matter the deficit or if it is the very first lb (excluding water weight) or the very last. I get it might be tougher to be in a deficit when one approaches their maintenance goal due to less calories to eat but if you stay in the deficit - mathematically you should still lose by that formula. Am I missing something?

Because you're thinking of things in a vacuum. The body is the MOST COMPLEX biological machine. Now IF all things were EQUAL and day to day you can pinpoint exact calorie burns and intakes, then CICO formula should be perfect. Problem is, you CANNOT account for hormone shifts. Since everything in the body is a reactionary response to stimuli, say one had a very tough day at work and stress was high. Or someone got some exciting news. Each of those creates a different chemical response in the body WHICH affects things like your metabolic rate.
It's why weight loss ISN'T linear. You can do the same thing, the same time, with the same rest, and exercise and diet, 2 weeks in a row and yield different results. Even if mathematically everything was perfect.

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 30 years and have studied kinesiology and nutrition

Water weight has no calories.

Stressing the body (with attempting faster fat loss than it wants) can increase cortisol, can increase water weight, can hide fat loss on the scale.

And CI does effect CO, and all the more so when closer to healthy weight.

Oh, and muscle mass loss doesn't hold to the 3500 per lb. Not that it's used as energy in any big way, but if extreme diet, then likely not building muscle back up that like all cells is torn down on regular basis.

scarlett_k wrote: »

That "last n pounds/kilos are the hardest" trope always grates me because it's nonsensical. My initial goal is at the upper end of a healthy BMI as I picked an arbitrary round number when I was 50 kg heavier. However now I am close to my goal I am considering losing another 10 kg. So technically I'm currently on the supposedly morr difficult "last n pounds/kg" whilst also possibly not being. It hasn't been any harder losing the weight I've lost this year vs the weight I lost last year. If anything it's been easier because I have learned so much in the four years I've been doing this that I feel like this year I am finally doing it exactly right, have listened to my body and upped my calories when appropriate (I've been intermittently much more active as I've been doing a lot of manual labour).

It's really not nonsense though. As you move to the lower end of your BMI, accuracy becomes more important because your deficit is likely to be very small. You're lighter, so you're burning fewer calories even with activity. The combination can make it harder. There's also some psychological factors at play -- sometimes people find it harder to have consistency when they're working on vanity pounds. It can be harder to limit portions to lose weight when you mentally know you're just doing it for looks and not health. There were days when I struggled not to conclude "I already met the goal of being at a healthy weight, why am I doing this?"

This doesn't mean that individuals always struggle with it, but as someone at the lower end of my BMI, I would say getting from overweight to normal weight was much easier than getting from normal weight to lower end of normal (but still worth it for me personally).

ALSO those last pounds necessarily come at the end of a sustained weight loss program which means you've already been doing the thing a long time and, if you haven't been taking regular diet breaks, that comes with both psychological and physical repercussions.

cmriverside wrote: »

Yep.

I started at 220 pounds. Lost 65 of it pretty quickly, all-at-once in about eight months. That put me just under the top of my healthy BMI.

I thought the same thing scarlett_k did, like, "Well that wasn't really so hard." Because it wasn't.

I took a few months off and then got back at it to lose the last 20.


Took me a year. And I was hungry. So hungry. Even though I knew my calorie needs because I'd been logging food for over a year and doing consistent exercise, eating well yadda yadda. Small deficit, 250 calories per day.

Oh my, for me those last pounds were - and still are - the reason I won't go back up in weight. It was super hard for me.

So hungry.


Have I mentioned my hunger??

I've done many a contest and HUNGER sucked. Getting down to my lowest (7% BF) was so hard and it usually was only a 10lbs drop. 12-16 weeks of dieting. After my 7th contest, I was done.

A.C.E. Certified Personal and Group Fitness Trainer
IDEA Fitness member
Kickboxing Certified Instructor
Been in fitness for 30 years and have studied kinesiology and nutrition

The flippety flip side of it is that once I got to 20-21 BMI it hasn't really been too hard to stay here. I'm really happy with how I look and I get to eat all my favorite foods (not every day, but ya know...) as long as I stay active.