When do you start seeing weight loss on keto?

When do you start seeing weight loss on keto
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For what seems like almost a decade now, keto has been one of, if not the most popular weight loss diet around the world and that’s because it’s superbly fast and effective.

So, when do you start seeing weight loss on keto?

Well, that depends on what you mean by “seeing weight loss”. If it means the number on the scale, a week on keto is going to get you faster results than most any other type of diet. If it means visually, like on the mirror or from other people, I say about 2-3 months. 

That being said, there’s more to keto than just slipping into tighter jeans.

It’s quite polarizing, actually, as a lot of the opinions are entirely different. For example, some people say you shouldn’t do keto at all while others swear by it. There’s a gray area between the 2 sides though and I think that’s where the truth about this controversial diet lies.

We’ll get to the bottom of those issues in just a bit but first, let’s lay some groundwork.

What happens to your body in ketosis?

Or what is ketosis, exactly? It’s basically when your body uses fat for energy instead of carbs.

It’s a big deal because your body is normally supposed to turn carbs into glucose for energy. But, because you’re only allowed less than 50 g of carbs when you’re in the ketogenic diet, you won’t have enough glucose, so now your body is forced to use fats, turn them into ketones, and use them for fuel. 

That whole concept is why the ketogenic diet is great for fat loss in the first place, because you’re literally using what fats you have stored to survive.

To paint you a better picture, below is a basic timeline of what to expect on the ketogenic diet. It should also answer the question “how long does it take to lose weight on keto?”. Take a look.

What to expect on first week of keto

In your first week, you can expect to lose at least 2 lbs of weight, with many people actually reporting losing as much as 10-15 lbs.

It seems a little extreme but it’s totally normal since most of that is water weight.

Now, you might be asking:

Why do you lose water weight on keto?

It’s because of the carb restriction.

You see, your body has this thing called glycogen — your body’s main energy reservoir. It’s also made from glucose which, in turn, is made mostly from carbs you ingest. Moreover, research says that a gram of glycogen usually comes with 2-3 g of water.

Therefore, when you restrict your carb intake, you force your body to use your stored glycogen. And with every gram of glycogen you use, you also lose the water that comes with it.

This is why low carb diets generally lead to greater weight loss during the first few weeks compared to other more balanced diets.

During your first week of keto, you might also encounter the infamous keto flu.

When you run out of glycogen, your body is now compelled to use fat. This transition from glucose to ketones is theoretically what causes the keto flu. Per Harvard, this happens around 2-7 days after you start the ketogenic diet. Symptoms include:

  • Headache
  • Brain fog
  • Fatigue
  • Moodiness
  • Nausea
  • Constipation

You might experience difficulties with sleep as well, along with maybe a few other annoying symptoms.

Not everyone experiences the keto flu though. But if you’re unlucky enough to actually catch it (like I did), the symptoms usually go away after a day or a week, depending on how fast your body adapts.

Moving on…

What happens after a month of keto?

If you stuck to your carb restrictions, high fat requirements, and ate moderate amounts of protein like you’re supposed to, you should already be well into ketosis after a month.

This means that your body now runs on fat (ketones) instead of carbs (glucose), you’re well out of the keto flu, but perhaps more importantly to the topic, you’re losing weight at a more regular and consistent rate because you’ve already shed most of your water weight.

Per the CDC and the NHS, this should be around 1-2 lbs per week. That’s what a lot of other experts in the field recommend, too, by the way. Any more than that and it’s just not healthy and/or sustainable.

Also, since you’re now literally burning fat to function, this is where you’ll see the incredible fat loss that people talk about with keto. So, if you were still wondering, “can you really lose weight on the keto diet?”, I’m telling you right now that there’s a high chance you will.

And now that we’ve touched on the weight loss part of keto, let’s talk safety.

Is the keto diet safe long term?

Just from observation, I think this is where the debate on keto mostly stems from. But, also from the way I see it, it’s mostly on what you think is “long term”.

For example, some people seem to think that 6 months is a long time for a diet. Case in point, a study called the Long-term Effects of A Keto Diet In Obese Patients says that 24 weeks (6 months) on the keto diet can reduce triglycerides, blood sugar, and “bad” cholesterol, while also increasing “good” cholesterol. So, in that sense, yes, the keto diet is safe. Healthy, even.

However, others — and I’m honestly on this side of the coin here — others think that 6 months isn’t really all that long. As a matter of fact, StatPearls recently published an article (2020) and essentially said that they still consider 2 years on keto as short-term. More importantly though, research on anything after 2 years on the keto diet is so scarce, it’s virtually non-existent.

So, I guess the gray area here is that yes, keto is incredibly effective for weight loss and yes, it comes with a ton of health benefits. However, if you want to do this for the long haul, I suggest you get yourself a doctor’s appointment every so often just to be safe.

On a similar note, you might be asking:

How long should I stay on keto diet?

Like the issue on long-term safety, opinions here are pretty divided — and I say “opinions” because I haven’t seen a study that says you should stop keto after a certain amount of time. Experts and professionals do have stuff to say though.

Specifically, there’s a camp that says you can do keto indefinitely while some others say you shouldn’t go beyond 6 months.

The gist of what both sides are trying to say though is that you should stay on keto as long as it’s sustainable — and by sustainable, I mean that’s it’s not affecting your health or any other part of your life in a negative way.

Health-wise, if you’re experiencing any unusual symptoms or the doctor found that it’s making your health worse, I say it would be wise to stop regardless of how much time you spent on the diet.

Also, are the extreme nutrient proportions getting in the way of you celebrating your core relationships? Is it somehow disturbing your mental peace? Is it just too expensive to keep up with? Are there any other challenges that ultimately make it more challenging than it is rewarding?

If so, then keto probably isn’t for you, which brings us to…

Does keto work for everyone?

No, it doesn’t — and it all goes back to the macronutrient proportions. 

For one, cutting out carbs means you also eat less fruits and vegetables which can lead to deficiencies in several nutrients like vitamin K, vitamin C, and magnesium just to name a few. The lack of fruits and vegetables can also make you constantly constipated and no one wants that.

You can take supplements to counter the nutrient and fiber deficiencies but that’s just more money out of your pocket. Plus, I’m a firm believer in getting most, if not all of your nutrients from whole food. It’s more enjoyable and sustainable that way, I think, but hey, you do you.

On a totally different note, you could also get plenty of bouts of diarrhea as the ridiculous amounts of fat can overwhelm your gallbladder.

Keto probably isn’t the best diet for anyone with liver issues either because the conversion of fat to ketones happens in the liver. And, if you have issues with insulin (e.g. diabetes) and/or have high blood pressure, you probably should take more caution when doing keto, too.

Plus, you’ve got all the social and economic hurdles that we touched on, and not everyone can navigate through them. I, for one, know I couldn’t. Or at least not for an extended period of time.

With that said, you probably already have a sense of whether or not this diet is for you now. If you still think it is, then you’re probably wondering where and how to start. Let’s talk about that.

Where to start on the keto diet

Know your macronutrient proportions

You have to know exactly how much fat, protein, and carbs you’re going to eat because even the smallest slip ups can take you out of ketosis.

Let’s use the macronutrient ratios of the standard ketogenic diet as an example. On a 2000-calorie diet, you need those calories to be made of:

  • 75% fat
  • 15-20% protein
  • 5-10% carbs

Of course, each one of us has different caloric requirements. A 7-foot male football player would need significantly more calories than someone who’s 5’7” and working a desk job, for example.

But whatever your needs are, there’s calculators all over the internet that can help you navigate through your macros.

Perfect Keto’s calculator is what I used when I did keto because I thought it made things simpler, but use what you see fit.

Know what foods to avoid

I keep repeating myself here but, again, for the nth time, it all goes back to the strict proportions.

You know you’re supposed to eat a ridiculous amount of fat, almost completely cut out carbs, and eat a medium amount of protein but I think it gets so much easier if you know what foods you need to say no to.

We have a comprehensive list of ketogenic foods to avoid that you might want to check out but just to give you a glimpse, these include most fruit, starchy vegetables, most alcohol, rice and grains, and other stuff that you’d commonly pick up at the grocery store.

Start cooking your own food

When you do this, you know exactly what you’re eating and how much of anything you’ll be eating.

You don’t need to have any cooking experience to make good food either. Start with recipes that use whole food and easy cooking techniques. Eventually, you’ll get better and faster and hopefully gain more confidence to try more complicated recipes even after you’re done with keto.

Know what to do when your keto diet stalls

Regardless of whatever route you take to lose weight, there’s always going to be a chance that you plateau. It’s stressful any time this happens and even more so when you don’t know why.

So, if you ask me, this is a crucial bit of information that you should know when you get into the keto diet.

We get into this with more detail in our Why Am I Not Losing Weight On The Keto Diet Anymore? article but basically, you want to ask yourself these questions:

  • Are you still in ketosis? Because if you aren’t, that answers why you’re not losing weight anymore. Maybe try a keto stick to measure your ketone levels just to be sure.
  • How much food are you eating? Because even if you choose the right type of foods, eating too much of them can put the brakes on your weight loss.
  • Are your macronutrient proportions right? Because all it takes is a gram too many to take you out of ketosis.
  • Do you exercise? If not, you probably should. If you are, maybe you should change it up a bit.
  • How are you sleeping? Make sure you get at least 7 hours of sleep in since poor sleep has long been associated with worse weight loss results.
  • Have you been constantly stressed? Because chronic stress has also been linked to obesity.

On a similar note, you might be asking:

Will keto make you gain weight?

While it’s popularly used for weight loss, doing keto actually can make you gain weight especially if you’re not careful.

You see, fats — which you’re supposed to eat a lot of in keto — contains 9 calories per gram. That’s almost double the amount of calories per gram of carbs and protein which are both at 4 calories.

In a nutshell, I think if you know what foods to avoid, what to eat (and cook), how much of them you should be eating, and have the foresight to see what problems you might encounter, you’re pretty much all set to embark on your keto journey.

So, what’s next? What to do after keto diet?

Whatever your reason may be for quitting keto, whether it be from realizing how you can’t sustain it anymore or because you’ve accomplished your goal weight, you want to do it right.

That means not binging on all the carbs and protein you’ve missed out on the very same day you decide to stop. Rather, you should gradually introduce them back into your life while simultaneously cutting back on unhealthy fat.

For example, you could take out a few strips of bacon off of your breakfast and eat chicken with a side of avocados instead.

After you’ve achieved your goal weight with keto, you could also aim for more muscle. This should be easier now since you’re allowed to eat more carbs and protein.

You could experiment with other diets as well. I’ve seen many of my peers find success maintaining their weight after keto by slowly switching to intermittent fasting. You can do that, too, but if it were up to me, I recommend shifting to a clean eating lifestyle rather than another diet that may or may not even work for you.

With all this said, it’s nearly time to end this but before we do, here’s a recap of all the pros and cons we’ve touched on:

What are the pros and cons of the keto diet?


  • It’s insanely effective for weight loss based on countless anecdotal and scientific evidence
  • You lose a lot of weight on the first week (albeit most of it being water) which can be motivating to some people
  • You learn that you have the power to literally change how metabolism works which, I believe, can extend to other areas of your health (e.g. PCOS, insulin resistance, etc.)
  • It comes with several health benefits including better blood sugar levels, triglycerides, and a healthier ratio between “good” and “bad” cholesterol


  • The ratio between carbs, fat, and protein are so out of the norm. The carb restriction, in particular, is ridiculous.
  • It can be unsustainable to a lot of people largely because of its probable impact on health and relationships
  • There’s very little evidence (if any) of what good or harm it can do to your body should you decide to do it for more than a couple of years
  • The notorious keto flu just straight up sucks
  • It’s not for everyone. If you have liver or blood pressure issues, you might want to try something else.


If you’re looking for one of the most effective ways to lose weight, look no further than the ketogenic diet. I mean, you can lose as much as 15 lbs of weight in the first week alone! Of course, this number should taper over time but it’s incredibly impressive nonetheless.

However, you do have to put up with the insane macronutrient ratios and all the possible hurdles that may come with it.

If you think this diet fits you, I say go for it. But if not, don’t sweat it. There’s plenty of others to choose from.

Oh,  and share this with a friend, alright? Cool!

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