Can dieting damage your metabolism?

There’s a lot of discussion in the fitness industry about whether crash dieting can cause metabolic damage….

You are  working out consistently and intensely… plus eating carefully, but you are not losing weight (or not losing it as fast as you’d like or expect).
Or you were losing weight consistently… until recently. Now you’re stuck — even though you’re working as hard as ever.   Or maybe  when you were younger, you were super fit,  and you did fitness competitions. Maybe you did some crash diets. But now, even when you put in the same effort, you just can’t seem to get as lean…

What is going on??

Do you think your  metabolism could be damaged?  Has your metabolism slowed to a crawl? Are your hormones off? Is it really possible to GAIN weight from eating too LITTLE? Here’s what’s really going on — and how to solve it.

In my years as a coach/tainer, this question has come up over and over,
people are frustrated and confused. They have been doing everything they can, including eating less — maybe a lot less —  exercising sometimes for HOURS a day. In fact I HAVE done this! After I had my 6th child I exercised for 3 hours a day! (We will discuss doing too much ‘cardio’ later) So people who are eating less and they’re still not losing weight. In fact, they might even be gaining weight.
Look on the  internet  and you will find lots of explanations.
(Some people say that the laws of energy balance apply, and that people aren’t counting calories properly. Others call it “starvation mode”, or some weird metabolic or hormonal problem.)

So what’s the deal? Is there something wrong with them? Are their bodies broken? Is it all in their heads?

Or can you actually gain weight from eating too little?

Have you heard of the Law of Thermodynamics?  Or maybe you’ve heard it as energy balance. Or “calories in, calories out.”

If your not sure what this law is, this law of thermodynamics is energy that can neither be created nor destroyed.

This is what it means…
Thermodynamics is a way to express how energy is used and changed. When we eat, we take in energy in the form of food, and we expend energy through activities like:
breathing, circulating blood, food digestion etc… (basic metabolic functions)
movement, daily-life activity, purposeful exercise, etc.
producing heat (also called thermogenesis)

And… Energy balance (calories in, calories out) does determine bodyweight.
If we absorb more energy than we expend, we gain weight.
If we absorb less energy than we expend, we lose weight.
This has been tested over and over again by researchers, in many settings.
It’s as close as we can get to scientific fact.
There are other factors that could influence this simple equation, which can make things feel a little confusing:

Simply put, energy balance (calories in, calories out) does determine bodyweight.

  • If we absorb more energy than we expend, we gain weight.
  • If we absorb less energy than we expend, we lose weight


We do not defy the laws of thermodynamics.

But what about unexplained weight changes? That time you ate a big dinner and woke up lighter? When you feel like you’re “doing everything right” but you’re not losing weight?
Nope, even if we think we’re defying energy in vs. energy out, we’re not.
And what about that low carb doctor who implies that insulin resistance (or some other hormone) messes up the equation?
While hormones may influence the proportions of lean mass and fat mass you gain or lose, they still don’t invalidate the energy balance equation.

Measuring metabolism is tricky.

The fact is, your exact metabolic demands and responses aren’t that easy to measure.
It is possible to ‘approximate’ your basal metabolic rate —  (by doing a simple formula) in other words, the energy cost of keeping you alive. But measurements are only as good as the tools we use.
When it comes to metabolic measurement, the best tools are hermetically sealed metabolic chambers… kind of expensive.
We may have our “metabolism” guesstimated at the gym, or by our fitness trackers, as with calorie counts on labels, these estimates can be off by 20-30 percent in normal, young, healthy people. They’re probably off by even more in other populations.
Of course, if we could accurately measure how much energy you’re expending every day, and then accurately measure exactly how much energy you’re taking in and absorbing, we could decide whether you were truly “eating too little” for your body’s requirements.

So, unless we can exactly measure energy inputs and outputs from minute to minute, we can’t know for sure what your metabolism is doing and how it matches the food you’re eating.
So, most of the time, we have to guess. And our guesses aren’t very good.
Not only that, but the idea of “eating too little” is subjective.
Think about it. By “eating too little”, do you mean…
Eating less than normal?
Eating less than you’ve been told to eat?
Eating less than feels right?
Eating less than you need to be healthy?
Eating less than your estimated metabolic rate?
Eating less than your actual metabolic rate?
And how often does that apply? Are you…
Eating too little at one meal?
Eating too little on one day?
Eating too little every day?
Eating too little almost every day but too much on some days?

This can be exhausting!!
Most times, the problem is perception.

As human beings, we’re bad at correctly judging how much we’re eating and expending. We tend to think we eat less and burn more than we do — sometimes by as much as 50 percent.

(Interestingly, lighter folks trying to gain weight often have the opposite problem: They overestimate their food intake and underestimate their expenditure.)
It’s not that we’re lying (though we can sometimes deceive ourselves, and others, about our intake). More than anything, it’s that we struggle to estimate portion sizes and calorie counts.
This is especially difficult today, when plates and portions are bigger than ever. And energy-dense, incredible tasting, and highly brain-rewarding “foods” are delicious, cheap, and socially encouraged.

When people start paying close attention to their portion sizes using their hands or food scales and measuring cups, they are frequently shocked to discover they are eating significantly more than they imagined!

Im going to add a part 2 to this – for now, check proportion sizes, try to limit processed carbs. Make sure you are getting adequate protein, carbs and fat.

Protein is SO important for maintaining and building lean body mass. adequate protein intake is especially important if you have body composition goals as it helps ensure that any movement on the scale is a result of fat loss rather than loss of muscle mass.

Carbohydrates who often get a bad wrap but reality is that they are our bodies’ go-to source of energy. feeling sluggish and tired? struggling to recover from workouts? you may be consuming too few carbs

Fats  are important for regulating hormones and aiding in the absorption of nutrients. also, they make food delicious


… tracking your macros is not about being the crazy obsessed person who weighs all their food; it is about learning how to fuel your body properly by eating the right amount of food for your lifestyle and your goals. it is about balance.


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Im Cheryl- Im very passionate about Exercise + Nutrition + Health = Wellness!!! Anything and all things that fall under the umbrella of fitness. I have a degree in Exercise Science, and have been living it, studying and having fun with it!!!

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