Why intermittend fasting doesnt work … at least not the way you think!

Let’s get one thing straight: intermittent fasting (IF) is not magic. It’s just a tool. And like any tool, it only works if you understand what it actually does — and more importantly, what the risks are!

Most people start intermittent fasting because they’ve heard it boosts fat loss, increases growth hormone, improves focus, and even extends lifespan. Sounds amazing, right? But here’s the thing:

It doesn’t work the way you think.

Yes, fasting can help you lose fat — but not because of the fasting itself. It works because you typically eat fewer calories during a shorter eating window. That’s it. You could just as easily eat fewer calories without fasting and see the same results. No magic.

Let’s say you fast 16 hours and eat for 8. You skip breakfast, have lunch and dinner, and maybe a snack. If that means you’re in a calorie deficit, you’ll lose fat. But that has nothing to do with the fast. It’s basic math.

Now here’s the problem: some people start eating huge meals in that 8-hour window. They overeat because they’ve been starving all morning. They justify the giant portions because they “fasted.” But now they’re at calorie maintenance — or even surplus — and they don’t lose anything. Then they blame the fasting protocol.

It’s not the fast that failed. It’s the misunderstanding of how fat loss actually works.

Another myth: “Fasting increases growth hormone, so I’ll build muscle while fasting.” Yes, growth hormone does rise when fasting — but not enough to overcome the lack of amino acids in the bloodstream. If you’re fasting all morning and training hard in a fasted state, your ability to build or preserve muscle is compromised unless protein is dialed in aggressively during your feeding window.

This brings us to one of the biggest overlooked issues: muscle loss during fasting.

Your body doesn’t store protein the way it stores carbs or fat. So when you go for long hours — especially more than 12 to 16 — without food, there are no circulating amino acids in your bloodstream. And since your body still needs those building blocks for repair, enzymes, hormones, and immune function, it starts breaking down muscle tissue to get them. This is the risk – and this is where it becomes particularly bad for people our age. Because we already know that muscle mass reduce risks of cronic illness and increase longivity:

https://fitover40.blog/2025/06/23/why-you-need-3g-of-protein-pr-kg-bodyweight/

So yes — muscle loss can absolutely happen during fasting. Especially if you’re training in a fasted state, not eating enough protein overall, or doing this long-term without proper recovery. And the older you are, the more likely it is. That’s because of something called anabolic resistance. As you age, your body becomes less efficient at turning protein into muscle. That means you need more protein — and more frequent hits of it — just to maintain what you already have.

Now combine that with skipping breakfast and eating only two meals a day? You’ve got long gaps with no protein and limited opportunities to trigger muscle protein synthesis. That’s a problem if you care about performance, strength, or long-term health.

This is why some people lose muscle mass while intermittent fasting. Not because fasting directly destroys muscle — but because they don’t eat enough protein, don’t eat often enough, and don’t recover properly.

Also, let’s talk energy and focus. Some people feel sharper during fasts — others feel sluggish, distracted, or irritated. It’s individual. There’s no universal “cognitive upgrade” from fasting. What helps one person focus might wreck someone else’s day. Listen to your own body — not a biohacking podcast.

So, is intermittent fasting useless? No. But it’s not some magic solution for fat loss, longevity, or mental clarity. It’s just a structure. It can work for fat loss. But only if it helps you control your calorie intake and fits your lifestyle in a sustainable way.

And if you care about muscle mass (which you should — it’s the strongest predictor of longevity), then you need to ask yourself if skipping meals and squeezing all your nutrition into a small window is helping you — or hurting you.

Bottom line: Intermittent fasting doesn’t work because of fasting. It works if it creates a sustainable calorie deficit and fits your life. That’s it. No magic. Just math — and discipline.