The 5 Biggest Modern Myths On Fat Loss: Is Losing Weight Complicated?

Fat loss is complicated, or is it? In the past, it was generally agreed upon that to lose weight, you needed to move more and eat less. Perhaps a little blunt, but it captured the foundational mechanisms of fat loss.

However, over the years, the culture has overcomplicated weight loss, leading to a range of misunderstandings. In this article, we're breaking down the 5 biggest modern myths of fat loss that are making weight loss complicated. 

Key Points You Need To Know! Calories are a measurement of energy. This is real energy, measured by its ability to increase the temperature of water, that powers the human body. While the internal mechanisms of weight loss can be complicated (all body functions are), application to our lives is relatively simple. All calories are equal. What's different is the other nutrients and compounds found in food; calories are innocent bystanders. "Eat less, move more" summarizes the basic concept of weight loss. It is not meant to be, nor claims to be, an all-encompassing guide to losing weight. But it still works.

1. "We Burn Calories!"

Key Points You Need To Know! Calories are a measurement of energy used in nutrition  1 calorie = The amount of energy needed to raise the temperature of 1 kilogram of water by 1°C  Energy from the food we eat must be converted into usable energy found in ATP. This shifts our understanding; our bodies don't run on "calories" but on actual energy required to power every process in the human body.

"Calories In, Calories Out" is the foundation of fat loss. It means weight loss depends on two factors:

• How many calories do we eat?
• How many calories do we burn?

This is generally accurate and reflects how we discuss weight loss.

While this works for general discussion, the problem is that we don't burn calories!

Why It's Wrong!

We can't burn calories because a calorie is a unit of measurement!

In nutrition, a calorie is a unit of measurement for energy, specifically the amount needed to raise the temperature of 1 kilogram of water by 1°C (Osilla & Sharma, 2022).

This means we are "burning" energy, which is measured in calories.

When we say we burned 200 calories, we mean we used enough energy to raise 200 kg of water by 1°C; a lot of energy!

Why It Matters!

On some level, this may seem like some trivial nuance. But it's not.

When people talk about "calories," they sometimes treat them as an abstract concept. They're not.

Calories measure actual energy that is powerful enough to increase the temperature of water;  that's why you get hot when you train hard!

Going further, the energy found in food isn't even directly used to power the human body.

Rather, it must first be converted into ATP, your body's "energy currency". ATP is then used to power all of your body's functions and processes. And this is 100% necessary.

Understanding this shifts the conversation and reframes how we speak about energy. We are eating actual energy, and our bodies must convert it so that we can use it. 

2. "It's Complicated!"

Key Points You Need To Know! Every physiological process is complicated and multi-factorial, including fat loss Fat loss is governed by the balance of energy, and burning more than you consume Other factors can influence our balance of energy, but they don't override its importance

Lately, there has been an increase in posts and influencers suggesting that Fat Loss is more complicated than "Calories in, calories out" or "Eat less, move more".

In fact, when a post is made that suggests fat loss is determined by calories, it's common to see commenters say;

"You obviously don't understand fat loss!"

This happens even if the original poster is an esteemed or respected person within the fitness industry.

Why It's Wrong!

It isn't wrong to call fat loss complicated; it definitely is, as if every process in the body is highly complex!

For example, when we're dehydrated, we say "drink more water."

But here's what's actually happening:

• Water is ingested and enters the stomach.
• It enters the small intestine, where most is absorbed into the bloodstream.
• Electrolytes, especially sodium, help drive water absorption via osmotic gradients.
• Blood volume and plasma osmolality begin to change.
• Osmoreceptors in the hypothalamus detect these changes.
• The brain adjusts thirst signals accordingly.
• The pituitary gland releases or suppresses Antidiuretic hormone (ADH)
• ADH acts on the kidneys to increase or decrease water reabsorption
• The kidneys regulate how much water is excreted as urine.
• Cells maintain fluid balance through osmotic shifts between the intracellular and extracellular spaces.
• Excess fluid is excreted; insufficient fluid triggers conservation mechanisms.

Now imagine if someone said that drinking water doesn't matter because hydration is complicated. Does that change the fact that drinking will hydrate you?

Heck, we find the human body fascinating, but are thankful we don't need to think about all that every time we drink!

In short, the internal complexities and mechanisms of an action don't change its application or negate the methods we've used for over a century.

Why It Matters! 

It's 100% impossible for a single article to address everyone's specific situation; that's why they don't. But just because an article doesn't hit every nuance, it doesn't make its core message wrong.

Further, saying "it's complicated" while criticizing the only way people can lose weight isn't helping. It can also demotivate people and needlessly stress them out.

In reality, the basic concepts of calories and fat loss have been understood ever since Lulu Hunt Peters wrote the first modern dieting book, Diet & Health: With Key to the Calories, in 1918.

Energy balance is also the foundation for studies aimed at improving fat loss. When looking at how increasing ATP demand in futile cycles can improve fat loss, researchers state:

"Obesity results from an imbalance in energy homeostasis, whereby excessive energy intake exceeds caloric expenditure." (Brownstein et al, 2022).

The researchers' entire methodology is based on the assumption that weight loss and weight gain are determined by the energy balance. Or maybe they don't understand fat loss?

3. "Not All Calories Are The Same!"

Key Points You Need To Know! Calories are just energy, and energy is energy Different foods can affect various physiological systems differently, but this is due to other nutrients and compounds Calories are simply innocent bystanders and exist regardless of how healthy or unhealthy a food is.

Usually used to somehow prove that "Calories in, calories out" doesn't work, the idea is that calories from some foods don't have the same effect as calories from others.

As such, some calories have a greater effect on weight gain.

Why It's Wrong!

As we showed above, a calorie is simply a measurement of energy, and energy is energy. It's like saying, "Not all minutes are the same!"

2,000 calories from protein = 2,000 calories from fat = 2,000 calories from carbs!

Now, this doesn't mean that other nutrients won't affect the body differently;

• Protein has a higher TEF.
• High glycemic carbs can spike insulin.
• Trans fats are not the same as your omegas.
• Fatty, sugary foods can have a less pronounced effect on hunger.

A study by Gardner et al. (2015) illustrated this when participants followed either a low-fat or a low-carb diet. However, both were told to focus on whole foods.

After 12 months, both groups naturally ate about 500-600 fewer calories and showed similar improvements in body composition. This tells us two things;

• Whole and minimally processed foods make it easier to eat fewer calories.
• Calories of a low-fat diet and calories of a low-carb diet resulted in the same weight loss (because calories are the same!)

Why It Matters! 

This ultimately reflects the industry's fixation on calories, where it begins to ascribe nearly all physiological and metabolic outcomes to them.

Not only does this frame calories as the boogeyman, but it also distorts what they actually are: a unit of energy.

In doing so, it shifts attention away from other critical nutritional factors that deserve focus, such as:

• Sources of Protein 
• Fatty acids
• Vitamins
• Minerals
• Types of Carbohydrates

It's similar to how we might confuse money with an individual's character. A person's character is independent of how much money they have. A good person is still good whether they're rich or poor, and the same is true in the opposite direction.

When isolated, $100 is still $100. It doesn't matter whether it comes from a felon or a monk, a wealthy executive or a worker on the rig. If you find $100, you have no way of knowing whose it is.

Now imagine if people started using money to explain behavior. Rather than address a person's faults, they say it's because they have X amount of money or make X amount of money from a certain job.

That would confuse correlation with causation and assign influence where it doesn't belong. More importantly, it doesn't address the real issues and demonizes money instead.

In the same way, calories are being treated as the cause of complex physiological outcomes rather than a neutral unit within a broader system.

A more productive approach is to still acknowledge the importance of calories. However, we should shift focus toward overall diet quality, prioritizing whole and minimally processed foods while limiting ultra-processed options.

4. Fat Loss Depends On Hormones!

Key Points You Need To Know! Fat loss can be influenced partially by hormones, but they do not control fat loss. Many common explanations (i.e., thyroid) are generally overstated Hormonal dysfunctions that do exist can make weight loss more challenging, but they don't cause weight gain.

So this one isn't 100% false but rather greatly exaggerated. 

The argument usually goes something like; 

• "Obesity is controlled by hormones, not calories."
• "After 40, calories stop mattering, and your hormones take over."

Strong emphasis is often placed on carb intake and insulin, such as the carbohydrate-insulin model. Another common explanation is thyroid dysfunction (Hal et al., 2022).

Regardless, the idea essentially suggests that hormones are what really control weight loss, not balancing energy.

Why It's Wrong!

When we look at these theories, such as the Obesity-Insulin Model, mainstream proponents will act as if it's "decided" among nutritionists. It's not.

For example, the obesity-insulin model has been researched quite significantly. However, the majority of researchers still hold that energy balance is the primary driver of weight (Hall et al., 2015; Hall et al., 2022).

We see similar trends in other conditions, such as thyroid dysfunction, where the magnitude of certain mechanisms is often overstated (Harsini et al., 2024; Kirwan et al., 2026).

In PCOS, insulin resistance can influence appetite and activity levels, making weight loss more difficult, but it doesn't override calories.

Why It Matters! 

It should be noted that "Calories In, Calories Out" still understands there is nuance and doesn't deny the influence of other physiological processes.

Hormones definitely play a role in our metabolism and can be affected differently by what we eat. And while they can alter how our bodies use energy to an extent, they do not override the fact that our bodies run on energy.

This would be like arguing that resistance training and adequate protein intake don't build muscle simply because some men have low testosterone and have trouble putting on mass.

More importantly, most of these conditions may slow the rate of weight loss, but they do not inherently cause weight gain in the absence of a caloric surplus.

Identifying any hormonal dysfunction is 100% important, but calories will always be the main driver. 

5. "Eat Less, Move More Doesn't Work Anymore"

Key Points You Need To Know! "Eat less, move more" summarizes the basic concept of weight loss.  This adage is not meant to explain every aspect or variable in weight loss. There are a plethora of studies and personal experiences that demonstrate "eat less, move more" is 100% true. Criticism of "eat less, move more" has still failed to provide an effective alternative.

This is the granddaddy of all claims, all packed into one, criticizing both exercise and dieting.

It claims this traditional fat-loss advice is outdated somehow because fat loss is "multi-factorial" and there are some variables you have no control over, like genetics.

Why It's Wrong!

Again, this topic is far too complex to fully address here, so go check out this article.

But essentially, this argument relies on rhetoric, mischaracterization, and misuse of studies. For example;

• Saying that hormones can "wreck" your metabolism
• Suggesting exercise can actually increase appetite or decrease activity, which negates your effort
• Overstate or exaggerate any negative effect of diet and exercise, usually using extreme examples such as diets using 400 calories a day.

It also ignores the fact that it works and has worked, nor have they provided other alternatives. A few meta-analyses to consider:

• Exercise alone can be superior to diet alone (Clark, 2015).
• Exercise + Diet is superior to Diet alone for weight loss (Clark, 2015; Wu et al., 2009).
• Exercise + Diet is superior to Diet alone for long-term adherence (Wu et al., 2009)

Why It Matters! 

We're not sure what the primary message is since these claims rarely include alternative methods.

And that's the problem: What are people supposed to do if diet and exercise don't work?

Ironically, when outlets actually do provide a solution, it always comes back to "eat less, move more." This makes the messaging even more confusing.

For example, Eating Well published an article titled, "Why 'Eat Less, Move More' Doesn't Actually Work for Weight Loss, According to Dietitians".

They cite a study that showed when people concentrated on nutrient-dense foods, they consumed 500 fewer calories per day without calorie counting.

Their argument was that "not all calories are equal" because some foods will naturally fill you up easier…but they still ate less! 

The Reality Of Fat Loss: Why It Really Matters?

Telling people that fat loss is complicated is what makes it complicated and why the public is still confused.

As we've mentioned, there are many variables that play a role in fat loss, and there is great variability between people.

Regardless, the foundational tenets that apply to everybody are actually pretty basic: achieve a caloric deficit.

This is why we always encourage individuals to attack fat loss from multiple angles, including;

• Concentrate on whole foods and get in a slight caloric deficit.
• Follow a resistance training program at least 2X a week.
• Increase basic physical activity; aim for at least 7,500 steps a day.
• Use cardio conditioning 2-3 times a week.
• Ensure you get plenty of sleep.

Following a plan that seeks to optimize your activity, diet, and recovery puts you in the best position to lose fat, no matter how complicated your personal situation is. And while some may have been dealt with less favorable conditions, we want to encourage them and give them practical tools to make weight loss easier!

References

1. Brownstein, A. J., Veliova, M., Acin-Perez, R., Liesa, M., & Shirihai, O. S. (2022). ATP-consuming futile cycles as energy dissipating mechanisms to counteract obesity. Reviews in endocrine & metabolic disorders, 23(1), 121–131. https://doi.org/10.1007/s11154-021-09690-w
2. Clark J. E. (2015). Diet, exercise or diet with exercise: comparing the effectiveness of treatment options for weight-loss and changes in fitness for adults (18-65 years old) who are overfat, or obese; systematic review and meta-analysis. Journal of diabetes and metabolic disorders, 14, 31. https://doi.org/10.1186/s40200-015-0154-1
3. Gardner, C. D., Trepanowski, J. F., Del Gobbo, L. C., Hauser, M. E., Rigdon, J., Ioannidis, J. P. A., Desai, M., & King, A. C. (2018). Effect of low-fat vs low-carbohydrate diet on 12-month weight loss in overweight adults and the association with genotype pattern or insulin secretion: The DIETFITS randomized clinical trial. JAMA, 319(7), 667–679. https://doi.org/10.1001/jama.2018.0245
4. Kirwan, R., Peele, L., Nuckols, G., Kohlhoff, G., Cabré, H., Olenick, A., & Steele, J. (2026). Resting energy expenditure of women with and without polycystic ovary syndrome: a systematic review and meta-analysis. medRxiv : the preprint server for health sciences, 2025.12.03.25341536. https://doi.org/10.64898/2025.12.03.25341536 
5. Hall, K. D., et al (2015). Calorie for calorie, dietary fat restriction results in more body fat loss than carbohydrate restriction in people with obesity. Cell Metabolism, 22(3), 427–436. https://doi.org/10.1016/j.cmet.2015.07.021 
6. Hall KD, Guo J. Obesity Energetics: Body Weight Regulation and the Effects of Diet Composition. Gastroenterology. 2017 May;152(7):1718-1727.e3. doi: 10.1053/j.gastro.2017.01.052. Epub 2017 Feb 11. PMID: 28193517; PMCID: PMC5568065. https://pubmed.ncbi.nlm.nih.gov/28193517/
7. Hall, K. D., et al. (2018). The Carbohydrate-Insulin Model of Obesity Is Difficult to Reconcile With Current Evidence. JAMA internal medicine, 178(8), 1103–1105. https://doi.org/10.1001/jamainternmed.2018.2920
8. Hall, K. D., et al. (2020). Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain: An Inpatient Randomized Controlled Trial of Ad Libitum Food Intake. Cell metabolism, 32(4), 690. https://doi.org/10.1016/j.cmet.2020.08.014
9. Hall, K. D., et al.  (2022). The energy balance model of obesity: beyond calories in, calories out. The American journal of clinical nutrition, 115(5), 1243–1254. https://doi.org/10.1093/ajcn/nqac031
10. Wu, T., Gao, X., Chen, M., & van Dam, R. M. (2009). Long-term effectiveness of diet-plus-exercise interventions vs. diet-only interventions for weight loss: a meta-analysis. Obesity reviews: an official journal of the International Association for the Study of Obesity, 10(3), 313–323. https://doi.org/10.1111/j.1467-789X.2008.00547.x