Meal Timing, Thermic Effect of Food, CICO, and ‘Starvation Mode’ – Real or BS?

is starvation mode a myth?

“If you don’t eat enough calories, your body will go into ‘starvation mode’ and it will hang onto fat, and you will gain weight.”

“You should eat six small meals instead of three to lose weight.”

I’m sure you have heard these before. 

The girl from accounting says them. 

I used to say it myself. Though I had no proof, it sounded like it made sense. I mean, our bodies respond to stress in times of crisis – so surely it is designed to literally ‘stall’ metabolic processing so that we don’t die?

This blog post is all about popular things people say to justify why losing weight is complicated and futile.

Spoiler alert: It’s not. But let’s look at the first item on our list:

Thermic Effect of Food

First, look at TEF – the thermic effect of food or the amount of energy expenditure above the basal metabolic rate due to the cost of processing food for use and storage. (Whew – that was a mouthful!) The TEF averages about 10% of a person’s caloric intake and varies based on macro groups – i.e. dietary fat is easier to process than protein. For example, when you consume 100 calories of protein, your body will only provide energy for 70-75 calories. In contrast, if you eat 100 calories from fat, your body will provide energy for around 97 of those calories.



Then comes the ‘How many meals/times should I eat per day’ discussion. Much speculation (and misinformation) about how much and how often a person eats affects their overall metabolism and weight loss efforts.

Again, something I believed but discovered through personal experience is also not true.

That’s where academic and scientific studies can help us to separate fact from fiction.

A recent study conducted by the University of Ottawa found that increasing meal frequency does not promote more significant weight loss when observing the weight loss progress between two groups of obese men and women. Each group was administered either a high-fat frequency (three meals and three snacks per day) or a low-fat frequency (three meals per day, no snacks) diet for eight weeks. Each group was instructed to complete the study under the same amount of energy restriction (total calories consumed). 

So, if eating three, four or six meals timed throughout the day is what works best for you – go for it, but know that there is no one hard and fast rule regarding the number of meals you eat per day.

What it comes down to is our next item, calories.

CICO (Calories In, Calories Out)

Many people don’t believe this, but when it comes to weight loss, gain, or homeostasis—it’s calories in/calories out (CICO). 

That is the rule, but some exceptions and variables make the concept not 100% foolproof. An example of an exception would be in individuals with underlying metabolic and hormonal conditions and those who are not addressing the issue through medical and dietary means. And an example of variables that impact CICO is the thermic effect of food concept explained above.

Hormonal conditions can prevent weight loss or even cause excessive weight loss or weight gain. Ultimately a combination of medication and diet working in harmony (for example, a low GI or ketogenic diet for individuals diagnosed with Polycystic Ovary Syndrome to combat insulin resistance) along with a suitable caloric intake can help to regulate this issue. In some cases, without the need for prescription medication. Notice that calories continue to factor in this situation despite a change in dominant macros levels.

It is true that when you reduce calories and lose weight, the body’s required calories will also decrease. I think this is where people cling to ideas like starvation mode and long-term weight loss are unsustainable.

Here’s the deal: If you change your lifestyle (i.e. lower your caloric intake and increase your physical activity) and then, after reaching your goal, go right back to eating the way you did before and not exercising – you’re going to gain that weight again and probably more. That doesn’t mean your efforts didn’t work – you stopped being consistent and didn’t adjust your lifestyle accordingly. Many people go through this when they don’t address the underlying issues they have with food.

You can read about whether or not you have a toxic relationship with food here.

Total daily energy expenditure (TDEE) and adaptive thermogenesis. 

TDEE comprises resting (BMR – Basal Metabolic Rate) and non-resting energy expenditure (the combination of exercise energy expenditure, TEF, and non-exercise activity thermogenesis.)

Adaptive thermogenesis refers to the underfeeding-associated fall in resting and non-resting energy expenditure (REE, non-REE) – aka eating less than the body requires at rest vs when the body is active. 

Simply stated (sort of):  If a person eats fewer calories than their body requires at rest, they will create a surplus, and their body will lose weight. The more active this individual is, the more calories they will burn and use in tandem with a reduced-calorie diet, potentially creating more significant weight loss results.

As the body reduces in mass, the caloric requirement will also drop — and as this happens, cutting calories further will adjust the body to continue to lose weight or adapt/increase caloric intake to create an energy equilibrium, which will result in maintaining the loss of weight.   This is a simplistic overview and can vary for individuals with hormonal imbalances and body composition variances. 

‘Starvation Mode’ (and that famous weight loss reality show)

A few years ago, a study by the Journal of Obesity measured long-term changes in resting metabolic rate and body composition in The Biggest Loser contestants.  

When published, I was caught in an 18-month period where I read all of Dr Linda Bacon’s research and books and immersed myself in the HAES community. ( I am in NO way saying that I had lost my mind to believe any of the studies Dr Bacon has done, but I have since changed my mind about some of it – but that’s for another post.) As a result of this interest, I was very taken in by this study as I, as a fitness and nutrition professional, had found the show problematic in many ways. 

The Obesity study showed how The Biggest Loser contestants had regained weight loss on the show and damaged their metabolisms. 

Okay, I have dealt with this when working with clients who want to lose weight. Like yesterday, most people want it off and think that cutting out entire food groups or creating huge calorie deficits daily is the only way. However, the deception is that sustainable weight loss is impossible for obese individuals, and that is not true. And while those methods may help them rapidly lose weight, they will likely not keep it off, which is what this study proves.

“Diets don’t work.” Okay, no, they don’t know when they are ‘crash diets‘ or unsustainable and highly restrictive.

Hollywood juice diets, master cleanses and ‘detox’ – oh, how I LOATHE – pills will help you lose water weight in the form of excessive bowel movements and carbohydrate restriction. 

Cutting back 500-1000 calories per day and adding 150 minutes of cardio per week will help most individuals lose 1-2 pounds per week and create a sustainable lifestyle (and weight loss).

The difference between a person like a contestant on The Biggest Loser and an individual who decides to cut 500-1000 calories per day and incorporate more physical activity into their lifestyle is the rate and severity of the weight loss between their starting point, the timeframe and the overall amount of weight loss. 

TBL contestants were restricting calories at a severe level while also performing hours and hours of physical activity per day; this is the epitome of ‘crash dieting’!

And while it may seem like a contradiction to say ‘starvation mode’ isn’t a thing, the following example is one of those exceptions I addressed earlier in this post:
When a person who is 100+ pounds overweight goes from eating 4000 calories per day to consuming 1000 calories per day overnight, they will create a 3000-calorie daily deficit, which over a week amounts to a 21,000-calorie deficit or roughly a six-pound (2.7 kg) weight loss. 
Now add 5-7 hours of physical activity daily, and we’re talking an additional 1500-2000 exercise energy expenditure deficit in addition to the caloric deficit, so we’re talking something like 35,000 calories or 10 pounds (4.5 kg) per week. 

In addition to TBL contestants’ severe deficit and exercise energy expenditure, we could also talk about the levels of cortisol, ghrelin and leptin that become impacted by the stress of limiting calories and performing that level of physical activity seven days per week. Messing with stress and hunger-controlling hormones will make the body physically crave food because, at that point, it is in a state of crisis. That is incredibly unhealthy, unrealistic and unsustainable. That is what you do in an extreme competition or game show or …oh, wait, that’s what The Biggest Loser was. 


I’ve heard people in support of Dr Bacon’s work say that The Biggest Loser study confirms everything they’ve said about how they cannot lose weight and that their experiences with restriction caused disordered eating and, therefore, they are fat, aren’t going to apologize for it or participate in diet culture when it is clearly futile. 

Weight loss is a simple concept but something challenging to put into action. I am not arguing that weight loss is challenging – especially when the starting weight is 100 pounds or more above what a healthy (and I’m using the BMI chart very loosely here) for their height should be. Those reasons are more about the emotional component of food and a person’s relationship with itespecially when that emotional component is a symptom of trauma.

Weight loss is a simple concept but challenging to implement, and those reasons are more about the emotional component of a person's relationship with food #eatingpsychology #coaching #weightloss #health. Click To Tweet

Diet culture, in my opinion, is the crash diet/snake oil salesman approach to weight loss.  

Cleanses, weight loss teas and all of that bullshit which cuts corners or claims to suppress physiological urges to eat are gimmicks and do not offer a sustainable long-term approach to weight management. These things don’t work long-term because a) they are unhealthy, and b) they go against every facet of common sense – slow and steady – the science of sustainable weight loss.

If weight loss is something you want to achieve to improve your health and the life you lead, I hope this information has helped clear up some of the confusing rhetoric that exists. I want to stress that I am not here to tell anybody that they should lose weight or that it is the most important thing a person should focus on, but if it is something you have struggled with, this post is a good resource for healthy, holistic weight management and lifestyle choices.

TL/DR: Starvation mode – in the way it is most commonly framed (i.e. following a moderate dietary framework) – isn’t keeping you from losing weight. It is not easy, but it is also (for the most part) not super complicated. Weight loss is a balanced science and is both adaptable and delivers results. But those results vary depending on where you start from, how you approach these changes, and if you’re ready to make long-term, sustainable lifestyle choices to maintain the loss. The best place to start is to want to start, and the best way to keep going is to remember why you started. 




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