The Bottom Line: Calories in, calories out is not wrong – it is incomplete. It describes what happened but tells you nothing about why it happened or how to fix it. The missing variable is insulin. Fix the hormonal environment through low-carb, healthy-fat eating, and your body regulates appetite and fat storage on its own.
Why calories in, calories out fails men who are already doing everything right
You track your calories, you hit the gym four times a week, you feel hungry every afternoon, and you lose 2kg in three months. You did what you were told. It didn’t work.
Nothing went wrong with your effort. The model failed you.
Calories in, calories out is true as a bookkeeping exercise. If your body uses more energy than it receives, you will lose weight. That part is not in dispute. The problem is that this framing treats the body like a passive system – a furnace that burns whatever you put in at a fixed rate. It is not.
The body is a hormonal system. It actively regulates how much you eat, how hungry you feel, and whether incoming energy gets stored as fat or burned. And the hormone running that operation is insulin.
When you understand insulin, the calorie model stops looking like the answer and starts looking like a description of a symptom.
What does insulin actually do?
Insulin is released by the pancreas every time you eat carbohydrates. Its job is to move glucose out of the bloodstream and into cells for energy. That’s the part everyone learns.
But insulin has a second job most people don’t know about: it signals your fat cells to store energy rather than release it.
When insulin is high, fat burning stops. Lipolysis – the process of releasing stored fat for fuel – is suppressed. Insulin inhibits lipolysis and promotes fat storage. You cannot burn body fat while insulin is elevated. The biochemistry does not allow it.
For men eating a standard Western diet – three meals a day, plenty of bread, pasta, rice, and snacks built around processed carbohydrates – insulin is elevated for most of the waking day. Not dramatically. Just chronically. Just enough to keep the fat storage switch stuck on.
You can be in a caloric deficit and still not lose fat efficiently, because the hormonal environment is fighting the arithmetic.
This is why Jason Fung, in The Obesity Code, frames obesity as a hormonal disorder rather than a calorie disorder. The calories are a downstream effect of a broken signalling system, not the root cause.
What is the appestat, and why does it matter?
Prof. Tim Noakes introduced the concept of the appestat – the brain’s hunger regulation system. It works like a thermostat for appetite. When it’s functioning properly, you eat until you’re satisfied and stop. You don’t need to count anything.
Noakes is direct about what breaks it: high-carbohydrate foods, particularly the processed kind engineered for maximum palatability. These foods override the appestat’s feedback loops and push you to eat past the point of need. The hunger is not a failure of willpower. It’s a hormonal signal that has been hijacked.
His framing on this: “Weight gain cannot occur without the ingestion of more calories than are needed by the body. In this sense the energy balance model of obesity is correct. But the point is that the over-ingestion of calories cannot occur if the brain appestat is functioning properly, as it did in 1980.”
And then: “The appestat of the obese must fail because it is especially susceptible to the appetite-stimulating effects of high-carbohydrate foods, especially those found in modern processed foods that are designed with the single goal that they are highly addictive.”
That is the mechanism behind why calorie-restricted diets fail long-term. You are trying to manually override a system that is supposed to self-regulate. The restriction produces hunger. The hunger wins eventually. The weight comes back. You blame yourself.
Don’t blame yourself. Change the inputs.
Does this actually work with real men, or is it theory?
Martin is an engineer in his mid-50s. Before working with me, he spent three months tracking calories and training at the gym. He lost 3kg. Hungry most of the time, tired, and couldn’t understand why his consistent effort was producing such a modest result.
In 12 weeks on a low-carb, healthy-fat approach – no calorie counting – he lost 12kg. His words: “I’ve probably added at least a decade to my life.”
Same effort. Different hormonal environment.
Craig is a retired army officer. He came in at 105kg. Four months later, 90kg. 15kg gone, blood markers improved across every measure. He said it was almost embarrassingly easy. Not because it required no discipline – it did. But once insulin was regulated and hunger signals were working properly, white-knuckling through hunger wasn’t part of the equation.
Clint was a different case. He was a Type 2 diabetic on Metformin when we started. HbA1c at 6.5 – in the diabetic range. In 12 weeks it dropped to 5.9, moving him into remission. He came off Metformin. He also came off cholesterol and triglyceride medication he’d been on for 10 years.
The weight loss was the secondary result. Fixing the diet fixed the blood chemistry that was driving toward serious disease. That’s what changed.
None of these results came from counting calories. They came from changing what was being eaten – specifically by cutting carbohydrates and removing the insulin response that was keeping fat stored and hunger elevated.
Why do so many personal trainers still push calorie counting?
Because it’s what they were taught, and because it sounds logical.
The energy balance equation is easy to teach. It’s intuitive. It turns a complex physiological problem into a maths problem. Eat less, burn more. If it’s not working, eat less or burn more. The model never fails in theory – it just produces a moving target that always blames the patient.
The other problem is that accredited personal trainer courses don’t cover nutrition at the depth required to actually help someone who has had weight problems for years. The result is trainers applying a caloric deficit model to a hormonal problem, wondering why it isn’t working, and eventually deciding the client isn’t compliant enough.
I’m based in Melbourne. I’ve been doing this for 14 years, coaching over 850 men across Australia and internationally. The men who come to me have usually already tried the calorie approach. They didn’t fail. The model failed them.
Gary Taubes, in Why We Get Fat, makes this point directly. The conventional wisdom says we get fat because we eat too much and exercise too little. Taubes argues this gets causality backwards. We eat too much and exercise too little because something is making us fat – and that something is the hormonal effect of carbohydrates on insulin and fat metabolism.
Eating less is a response to the symptom. Changing what you eat addresses the cause.
What does a low-carb, healthy-fat approach actually look like?
Real food. Meat, fish, eggs, vegetables grown above ground, full-fat dairy, quality fats. No processed carbohydrates, no sugar, no seed oils. Not a meal plan you follow for eight weeks and abandon – a way of eating that, once your appetite regulation is restored, becomes sustainable without constant effort.
The first week or two are rough. Your body has been running on glucose for years. Switching to fat as a primary fuel – fat adaptation – takes time. Some men experience fatigue and irritability during this window. It passes.
After that, what I hear from men consistently: hunger drops, energy stabilises, afternoon crashes stop, sleep improves, the waistline starts moving. Not because of willpower. Because the system is working the way it was designed to work.
Remove the processed carbohydrates and the appestat does its job again.
What if my doctor says I need to count calories?
Most GPs are working from the same playbook as most personal trainers. The caloric deficit model is the standard of care. Your doctor is not wrong to reference it – it is what the consensus guidelines say.
The problem is that consensus guidelines are slow to update, and the metabolic research of the last 20 years has been building a very different picture.
If your doctor is recommending Metformin, statins, or blood pressure medication – or if those conversations are getting closer – the question worth asking is whether dietary intervention can address the root cause rather than managing the symptoms with drugs.
The evidence for low-carb, healthy-fat intervention on Type 2 diabetes, metabolic syndrome, and cardiovascular risk markers is substantial. Clint’s HbA1c going from 6.5 to 5.9 in 12 weeks – and coming off medication he’d been on for a decade – is not unusual. I see that pattern repeatedly.
Talk to your physician. Bring the data. Blood markers don’t lie.
Find out exactly what's keeping you stuck.
Frequently asked questions
Why doesn’t calorie counting work for men over 40?
Calorie counting fails because it treats all food as equal and ignores the hormonal response that drives fat storage. As men age, insulin sensitivity decreases, making the hormonal component of weight management more significant. Reducing carbohydrate intake lowers insulin levels, which allows fat to be burned rather than stored – regardless of total calorie intake. Read more about it here.
Is calories in calories out actually wrong?
It is incomplete rather than wrong. The energy balance equation is accurate as a description but misleading as a prescription. It says nothing about why some men eat more calories than they need, or why hunger signals malfunction after years of a high-carbohydrate diet. Fix the hormonal environment, and the calories tend to take care of themselves.
What is the appestat and why does it matter for weight loss?
The appestat is the brain’s appetite regulation system, described by Prof. Tim Noakes. When it functions properly, hunger signals switch off when you have eaten enough. High-carbohydrate and processed foods disrupt the appestat, causing chronic overeating that has nothing to do with willpower. Removing those foods allows the system to self-regulate again.
Does insulin really control whether you gain or lose weight?
Insulin is the primary hormone that regulates fat storage and suppresses fat release from adipose tissue. When insulin is elevated – as it is for most of the day on a typical Western diet – lipolysis (fat burning) is suppressed. You cannot efficiently burn body fat while insulin is chronically high. This is why low-carb, healthy-fat eating produces fat loss even when calories are not being tracked.
Do I need to count calories or track macros with your approach?
No. Calorie counting is the model this article argues against. The approach I use with clients is built around food quality and hormonal regulation – specifically cutting carbohydrates to lower insulin and restore proper hunger signalling. When that’s working, your body tells you when to stop eating. You don’t need a spreadsheet. Most men find this simpler to sustain than anything they’ve tried before, because they’re not fighting hunger the whole time.
What should men over 40 eat instead of counting calories?
Real food: meat, fish, eggs, vegetables grown above ground, full-fat dairy, and quality fats. Remove processed carbohydrates, sugar, and seed oils. This approach lowers insulin, restores appetite regulation, and allows the body to access stored fat for fuel. Most men find hunger decreases significantly within the first two weeks.
How long before a low-carb approach starts working?
The first one to two weeks involve an adjustment period as the body shifts from glucose to fat as its primary fuel. After that, most men report stable energy, reduced hunger, improved sleep, and measurable changes in waistline within four to eight weeks. Craig went from 105kg to 90kg in four months. Martin lost 12kg in 12 weeks. Neither was counting calories.
