Keto Works Fast. That's the Problem

Everyone knows someone who “lost 10 pounds in two weeks on keto.” However, nobody knows anyone who’s still on keto a year later.

And that's because keto is one of the least sustainable weight loss diets out there.

But before I explain why, let’s put ourselves in the shoes of someone who’s been trying to lose weight for a long time without success.

They’ve done the workouts. They’ve “eaten cleaner.” But the scale barely moves. Eventually, they start wondering if they just have a bad metabolism, or if weight loss simply isn’t in the cards for them.

Then they try keto.

And voilà - within one or two weeks, the scale is down ten pounds.

You'd be ecstatic right? You went from feeling hopeless to feeling like you just found the "magic diet" for weight loss. Psychologically, that kind of immediate feedback is powerful. It creates certainty before understanding ever has a chance to catch up.

That is why keto gets praised so highly in the beginning.

But the problem is 80-90% of the weight loss isn't fat. It's water.

The science behind this is because when you eat carbohydrates, they are transformed into a sugar called glucose (blood sugar). And then that excess glucose is stored inside your liver and muscles as something called glycogen.

Glycogen acts as a rapidly available store of energy. So naturally when you cut carbs, you deplete your muscles of glycogen. And glycogen holds water, which means your muscles are holding less and less water. So immediately this leads to a significant drop in water weight, which is that change on the scale that people see at the start of a ketogenic diet. And any sort of fat loss that occurs during this process isn't because your body switched to "burning fat," it's just because they simply ate fewer calories due to protein and fats being more satiating than carbs.

So now you might ask, "So what's the problem with all of this?" Good question.

While at first you might feel mentally sharper, and not feel too many drawbacks to this depletion of glycogen, they will come. Soon you will start to feel "flat" in the gym. Energy will go down, recovery will worsen, with your mood and motivation following.

What some people will describe as "fat adaptation" is often just the result of under-fueling your body.

Last summer I personally decided to try a low carb diet. I noticed when I had less carbs I had better mental clarity, and combined with the goal of wanting to get leaner I figured I'd just drop carbs completely and up my fat and protein to retain muscle during my cut. For a few days I felt great, mentally clear, light, laser focused. But then it all came crashing down.

My training performance fell off a cliff, every rep that used to feel easy was a struggle. Getting on the treadmill felt like a death sentence. Recovery started to fall behind. And worst of all, my mood and motivation got hit the hardest. I was incredibly irritable, tired all of the time, and just couldn't focus on anything.

If you are someone who trains relatively hard, resistance training at least 3-4 days a week, the truth is you need some carbohydrates. I am not saying you need hundreds of grams of carbs a day, but hard training runs on glycogen. And having a high output physically requires some sort of carbohydrates.

So that led to me creating a protocol that allowed me to have the mental clarity that came with a low carb diet, without suffering from the performance drawbacks that came with it.

This is simply called carb timing. You don't need carbs all day, you need them when your body can actually use them. Consume the carbs when you actually need them, reduce them when you don't.

For most people who train regularly, that means placing the majority of carbs around training. This is when glycogen demand is highest and performance actually benefits from them.

If you train later in the day, this can mean including a more complex carb source earlier in the day with a meal if you are aiming for a higher daily carbohydrate intake. Just make sure you stick to things such as sweet potatoes, rice, oatmeal, etc. I recommend waiting as long as you can to do this if you are aiming for mental clarity earlier on in the day.

Closer to training, many people do well with a lighter, easily digestible carb source about an hour to an hour and a half beforehand. Aim for enough to fuel the session without feeling weighed down. I usually go with Oatmeal or Cream of Rice with a scoop of whey protein personally.

If you train first thing in the morning, this is where nuance matters. Some people feel better training fasted, especially if appetite is low in the morning. If this is the case then you are fine to train fasted, just make sure you eat carbohydrates after the workout.

Post-workout is where carbs tend to be most valuable across the board. This is when glycogen replenishment actually supports recovery, performance, and adaptation rather than just spiking blood sugar for no reason.

Outside of training windows, keeping carbs lower tends to work better for mental clarity and focus, especially in the morning or during long work blocks. Large carb loads during these times usually contribute to sluggishness, and makes it harder to focus and get things done.

This carb timing approach has led to me being able to keep the mental clarity and output benefits that come with a low carb diet, but not have to suffer the performance downfalls that come along with it.

The moral of story is keto isn’t some magic diet. It’s a short-term illusion built on water loss and appetite suppression.

For people who actually train, the costs add up fast. Flat workouts, poor recovery, worse mood, and declining output.

Carb timing isn’t sexy, but it works. Keep carbs where they fuel performance and recovery. Keep them lower where they don’t.

Optimization isn’t about extremes. It’s about using the right tools at the right time.