What is the CICO diet and is it healthy?

CICO stands for "calories in, calories out" and when I recently saw an article with that title, I rolled my eyes into oblivion. The "CICO diet"? Ugh.

How did the way bodies function become a new diet with a fancy new name? Oh right, because you can turn anything into a diet if you slap a cutsie name on it and tell enough people it's the answer to fast and easy weight loss. Where IS that eye roll emoji when you need it? I digress... Full disclosure - I tracked calories over 12 years ago to lose 40lbs in about 4 months. It was both helpful and positive and dysfunctional and difficult depending on my frame of mind. As well, I have recommended tracking to my own clients in recent years, with caveats and depending on the circumstance. So, does that mean I think people should be doing the "CICO diet" to lose weight? Maybe. But mostly, no. Basically it's complicated and I'll answer why in detail in another post.

First re: that article though. What they describe as the “premise” behind this particular "diet fad" is not the premise for some new fad diet as they claim, it's actually the way bodies work.

Not even just human bodies, all bodies. If you feed your dog more food than his body needs to survive each day, his body will store the extra fuel. If you feed him less, he will burn it. It’s the biological basis upon which all bodies actually function – human bodies included.

There is not another diet on the planet that changes that reality. As a matter of fact, every single diet on the planet RELIES on that reality – that’s how they ALL create weight loss if you follow them.

The only thing diets and their arbitrary rules do is change HOW you create that deficit by restricting different foods or food groups depending on their individual rules. But they ALL work on the basic premise that you must eat less calories than you burn to lose weight.

That it’s. That’s all.

So this whole idea of “CICO” actually just removes the middle man. It gives YOU the power to lose weight all on your own without ANY one else’s food rules – which the diet industry does NOT like because if you start realizing that you can do it without them, you put them out of business.

The thing is, it will 100% work just as well as any other diet if you stick to it consistently. Study after study after study has proven that no one diet works any better than another when caloric deficits are equal. I’ve also personally and professionally seen it work over and over and over again. But does that mean you should do it? Like I said, more on that in another piece because we have to dig into that word, "work" more.

The article was infuriating for a number of reasons but also made some valid points so I wanted to talk about them all because this new "diet fad" is likely to appear in a newsfeed near you sooner or later if it hasn't already.

I’m going to do this a little differently than my usual blogs by specifically addressing their points with some direct quotes in green below:

They said: The CICO diet stands for ‘calories in, calories out’ and is based on the premise of eating fewer calories than the amount you burn. Scientifically, burning more calories than that you consume causes weight loss.

Again, as I already said that’s 100% true but the basic rule of human biology isn’t some new diet fad – this is actually the way bodies work.

They said: “But the idea that you can eat whatever you want and lose weight still has some limitations. Fitness trackers and apps all tell you how much you’ve burned off and how much you’re consuming so the diet is popular among lots of people. It certainly sounds easy – you get to munch limited portions of whatever you like and then burn it all off, shedding weight. It’s not the most sustainable though as it means you’re not focusing on quality and the types of foods you’re entering into your system.”

First re: sustainability. It's actually one of the most sustainable ways to lose weight for most people because you’re not suffering by eating crap you don’t even like and you’re not at as high a risk of bingeing from food restriction. But it’s also super unsustainable for many people because while you’re getting used to it, it’s time consuming and a huge pain in the ass.

Second, re: this comment in particular: “The CICO diet stands for ‘calories in, calories out’ and is based on the premise of eating fewer calories than the amount you burn. Scientifically, burning more calories than that you consume causes weight loss.”

I'm going to keep saying this because I want to make it CRYSTAL clear -- that’s not a crazy premise based on some new fancy diet fad. That’s actually the way our bodies work. We feed them calories that provide them nutrients and energy to function and stay alive and they burn those calories. Every body requires a certain amount of those calories to get through the day. This not a new concept, nor fad diet feature, it’s the way bodies have worked literally since the beginning of time. If we consume more than we burn off, we gain weight. If we consume the same amount that we burn, we maintain. If we consume less than we burn, we lose weight.

Again, not some new fancy diet feature, it’s how bodies work.

I’ll address the claims of no focus on choices more below but what surprises me about their criticisms is that they’re not even addressing the biggest ones that are actually really valid ones – it’s not a perfect science, rebound weight gain & the eating disorder risk.

The estimates most food apps give for the amount of calories in different foods can be off by as much as 25% AND they don’t take into account the fact that different foods are absorbed at different rates. For example your body will absorb more calories from one type of food than it will another based on a number of factors. For example, the more processed a particular food is, the more calories your body will absorb from it. So if you’re eating 70 calories of candy your body will absorb probably most of those 70 calories whereas if you’re eating a 70 calorie egg, your body will likely absorb less than that. (That’s a completely random and broad example just to make a point) Beyond that, apps can only estimate how much your body is burning. Outside of being tested in a lab, there’s no way to determine exactly how much your body actually needs or is burning of anything. Some foods make you feel full longer than others as well.

So it’s not an exact science and there is room for error. It is, however, a fairly decent guideline that’s the best chance we have of knowing, outside of getting tested in a lab.

As for rebound weight gain: 95-98% of people who lose weight on a diet will regain all the weight they lose within 1 year and as many as 2/3s of them will weigh 11lbs more than when they started within 5 years. Those stats are true regardless of what diet is done/how weight loss is achieved.

They said: "And while it can be a useful tool for quick weight loss, it’s not the healthiest. Since it’s about eating whatever you want, it might mean getting your calories from unhealthy snacks instead of healthy fats and proteins."

True. It’s not necessarily healthy. But at least it doesn't claim to be unlike all the other diets that lie and say they are.

Spoiler alert: DIETING is NOT healthy, especially roller coaster dieting. And most of the most popular fad diets on the market that claim they are healthy, are not. Diets that eliminate entire food groups that have nutrients your body needs like its primary, preferred source of energy (carbs), or fiber or B12, etc -- also not healthy. And our bodies know that - that’s actually WHY they make us prone to caving or binges because our bodies KNOW they need those things and they work really hard to force us to give them what they need.

Further weight fluctuations bring many side effects that can harm your physical health. It’s been linked to an increased risk of cardiovascular disease, Type 2 diabetes, high blood pressure and continued weight gain.

Yes, you heard that right – weight gain. People who diet (any diet) are far more likely to gain weight over time than those who don’t.

If you're following someone else's food rules, especially if you're doing it ONLY to lose weight, you're actively working at unlearning your body's innate instincts. That's not mentally or physically healthy.

You're also putting yourself at an increased risk of a lifetime of disordered eating habits, bingeing behaviors and many other eating disorders. Super NOT mentally healthy. There is a direct relationship between dieting and eating disorders and eating disorders have the highest mortality rate of all mental illnesses. Their rate has doubled in the last 20 years.

The upside to relying on snacks (though they portray it as a down side) and learning to ignore other people’s food rules is it can give you a chance to learn about how different foods make you feel. Rather than trying to force yourself to eat whatever’s on your diet and has been pre-determined by someone else’s rules, you have ALL the power to decide what goes in your body. As it SHOULD be. It’s YOUR body.

It’s far more empowering than just mindlessly trying to force yourself to eat what someone else says you’re supposed to because the choice about what you eat is yours. You start noticing that if you make a choice like fast food, or something high in fat or sugar, it may be about the only thing you can eat all day to stay within your "calorie range" and doing that usually results in feeling pretty crappy. It can, when done RIGHT, teach you to actually WANT to start making “healthier” choices – but again, only when done right. Most people don’t really use it for this and instead just obsess over numbers and become scared of calories.

They said: ‘At the core of it, it’s true that calories will rule things when it comes to weight loss,’ says Dawn Jackson Blatner ‘If you’re eating just a tonne, you’re not aware of calories, you will not be successful. (…) "

Here I just want to point out that even the person they’re interviewing about why it’s supposedly bad (and who’s selling a diet book) is admitting that calories are really all that matter when it comes to weight loss.

The article further notes re: the author they quote: "The aim of his diet is to create a calorie deficit but not all calories are created equal."

So the person they’re getting to chime in on whether or not it’s effective (it is, as much as any other diet that is) or healthy (again, for the reasons I’ve already listed dieting in general is not healthy so whether or not it’s healthy is a moot) …is someone selling their own diet and who wants to tell you what you should and shouldn't eat based on his rules.

Please remember that anything that encourages people to learn about what’s in what they’re eating and connecting with their OWN bodies is bad for business to anyone selling a diet plan when you take their “healthy eating” advice.

They said: "So if you chomp 1500kcal of Mars bar throughout a day and then work it off, it doesn’t mean it’s a healthy choice."

Literally nobody ever claimed it is. As I already stated though, there are actually surprising benefits to doing that when there are no judgments or food rules present. When we’re taught to believe that things like mars bars are bad and that eating 1500 calories of them is horrible, we’re more prone to keep doing it. If we remove the rules and labels and start connecting with what our bodies are telling us they need, they’re going to start telling us we feel like absolute garbage when we do that and we’re going to be less likely to want to keep doing it. Our bodies don’t want to do those things and when we learn to listen to them, they tell us that!

Without the rules, judgment and fear of restriction that make us prone to continue punishing ourselves with restriction or binges, we start believing we actually deserve to feel good and the thought of eating 1500 cals worth of mars bars don’t even exist anymore.

BUT – there’s a very strategic way of learning that and merely obsessing over numbers and weight by just trying to do a “CICO diet” isn’t going to get you there.

Also, promoting the notion that we have to “work off” our food is deeply destructive and disordered eating territory.

They said: "Many have been critical of CICO as it forces people to count calories in each item consumed rather than enjoy the food they’re eating."

Absolutely untrue. The REASON simply allowing yourself to eat whatever you want (MAY) work a little better is precisely because you’re more likely to actually enjoy what you’re eating versus trying to force yourself to eat according to someone else’s rules because as they always say “nothing tastes as good as skinny feels” and other disordered attitudes like that.

There are far more truthful reasons to be critical of counting calories than relying on one with no merit so that’s silly.

Other reasons are, as I’ve already stated, it’s not a perfect science, any weight loss will almost certainly be reversed and it’s a pain in the ass so many people can’t keep it up.

And of course not the least of this next point:

They said, "The obsession with calorie-counting may even lead to problems like eating disorders which was the issue with Ocado’s saver option."

100% true, this is as valid a concern with tracking as it is with ANY “diet”. Restricting food for the purposes of weight loss puts you at a higher risk for eating disorders which is why we have to stop trying to restrict food for the purposes of weight loss – no matter what “diet” or rules the restriction and weight loss attempts fall under.

They said, "CICO might produce weight loss but getting your calories from any old food item can cause other problems to the body such as skin breakouts and lethargy. Calorie-counting may help, but it’s also important to look at where you’re getting it from and the benefits of it."

Sort of true with caveats… Counting calories works. 100%. Many of my clients have used calorie tracking apps and I have never had a single client in almost a decade who consistently tracked calories and didn’t lose weight. Never. Not one time ever. It works 100% of the time. As with everything, consistently is the key word. Anything you consistently do that puts you in a deficit will result in weight loss.

Haven’t you noticed that you could ask 50 different people who lose weight, HOW they did it and they’ll all tell you something different.

“I did keto” “I did ideal protein”

“I did whole30”

“I did intermittent fasting”

“I did beachbody”

“I did slim fast”

“I did weight watchers”


When someone tells you what diet they did to lose weight, all they’re really telling you is the means by which they created the caloric deficit they required.

The reality is that every single person you have ever seen who lost weight has done so because they ate in a deficit (that is, they ate less calories than they burned) consistently enough for it to count. That’s it. That’s the big magic secret you’ve searched for your entire life. It’s not the diet, it’s the deficit. The diet is just the means by which they create said deficit. I know I said that twice, I want it to sink in.

But again, it’s not an exact science so it can take some tinkering and that definitely doesn’t mean everyone should do it. For example, if you have a history of disordered eating, long term diet cycling, binge eating, emotional eating, etc… you should not. Those things need to be managed before you do anything else.

And it’s totally true that where our calories come from matters. Some foods are more nutritiously dense and will make your body feel and function better than others. 100%. But the answer to learning to eat those things more often is never to try to follow someone else’s rules about what they are. We have an entire diet and nutrition industry at war with itself, professionals in their fields fighting with each other over whose way is right – all fighting over who we should listen to about what’s best for our own bodies. They can’t even agree and we’re supposed to trust them to know better than our own bodies know?

And the entire time they’re fighting with each other over whose rules are the best rules, the world is getting more confused and no one is talking about our brain’s role in our food choices. You know, the computer that actually drives all our behaviours.

Everyone is ignoring the biggest factor of all – WHY are we eating the way we’re eating? WHY do we make the self-destructive food choices we make?

That’s WHY we spend so many years struggling with weight and food. The bottom line is that there are some really annoying and untrue statements floating around about the "CICO diet" (can we please stop labeling the way our bodies work as a diet?) but there are also valid and quite true statements -- that are true of ALL diets. So, should you do it? If you must make another weight loss attempt (if you've been making weight loss attempts for years, you really shouldn't!) but if you must, it's a more empowering option than trying to follow food rules and it's what I would recommend over starting another traditional style diet -- but, like all diets, it comes with many risks.

Like I said, it's complicated so I'll really dive into calorie tracking in my next post. On principle, I'm never using the phrase "CICO diet" again though. ;) If you're struggling with weight and food, I created The Cognitive Eating Academy specifically to help you answer those questions: why are you eating the way you're eating? Why are you making self-destructive choices? And how do you learn to stop? You join The CEA. Click here to learn more.

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Roni Davis
Cognitive Eating Founder

Writer, Producer, Host - It's All In Your Head Podcast

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Roni Davis spent over two decades struggling with weight, food (mindless, emotional and binge eating), an eating disorder, depression, panic attacks, and an anxiety disorder. She's also been a nationally qualified champion figure athlete, written for bodybuilding websites, was featured in a national fitness magazine, by Bodybuilding.com and spent almost a decade helping people transform their bodies as an award-winning personal trainer and nutrition and wellness coach.


After over two decades of her own personal weight & food struggles and almost a decade in the weight loss/fitness industry, Roni left the fitness industry and bundled everything she learned from her own recovery, from her time as a trainer & nutrition & wellness coach with everything she learned in her mindfulness-based cognitive behavior coach training, to create Cognitive Eating.  This allows her to guide and support people to live healthier lives through behavior and habit modification at the brain level, where it counts and will actually stick.

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NOTE: While counselors or therapists often use CBT to deal with mental illness or a patient’s mental/emotional conditions and/or processing trauma, MBCT & cognitive eating does not. My roll as a coach, in its most simple form, is to encourage, coach and/or act as a facilitator of a client’s self-reflection, decision making, planning for the future, and creating life changes. As an MBCT & cognitive eating coach, I am obligated to refer clients in need of mental or physical health therapy to an appropriate licensed professional.  

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