Keto Diet Benefits & Side Effects (First Week VS Long Term)

Keto Diet Benefits & Side Effects

Let's talk about the Keto Diet benefits & side effects.

As you may know, this diet is quite complicated.

While it may help with weight loss, it does so at the cost of health issues.

But let's see how reliable this is (in the first week VS long term):

  • What should you expect during your first week on Keto?
  • What about if you use it in the long run?

Keep reading to find out what you should pay attention to.

Note: This article is based on my own research on Keto diet.

Keto Diet Benefits & Side Effects (In A Nutshell)

Keto Diet is one of the most well-known diets out there.

However, it's also infamous for how restrictive it is.

So how good is it if you plan to commit to it long term?

It actually doesn't have any real benefits in the first week (except for losing water weight):

  • exhaustion
  • Keto flu
  • digestion issues
  • prone to nutritional deficiencies
  • risk of muscle loss
  • bad breath

As for positives, Keto may very well tame your appetite.

No doubt, this will make it easier to stick to the diet.

Simultaneously, it also makes you less prone to inflammation.

Last but not least, it can potentially be of help when it comes to cardiovascular problems.

However, it's advised to stay away from Keto if you have issues with your blood pressure.

As you can see, the benefits of this diet are nowhere near enough to deny the side effects.

Compared to other dietary regimens, Keto is quite harsh on your body.

For this reason, it's not recommended to commit to it permanently.

In fact, it's best to stay away from it altogether, unless you're a healthy person overall and your only concern is to lose weight.

Most health issues you have run the risk of being complicated by how strict Keto is.

If you were to ask me, it's really not worth the risk.

But if you're still tempted to give Keto a try, I recommend talking to a doctor beforehand.



#1 – First Week Benefits

Since you're reading this article, I take it you're thinking of starting a Keto diet.

Then surely you are aware of all the benefits that this diet claims to deliver.

However, this is a rather restrictive diet, so I recommend reading up about it as much as possible.

Yes, that means you also have to be aware of the less favorable aspects.

That being said, let's see what you should expect in your very first week of Keto.

Obviously, you're not going to get all its advantages so soon.

So what should you prepare yourself for?

1. Weight Loss

Let's start off with what you're interested in most.

Realistically speaking, how much weight can you expect to lose in the first week?

People have vastly different experiences when it comes to answering this question.

But that's only because every body is different.

Actually, lots of people say they lost a lot of weight when starting this diet.

However, it's most likely that this is just their water weight, not actual fat.

As per what we discussed in our Keto guide, this diet makes your body enter a state of ketosis:

  1. Your body goes from using glucose as fuel to consuming fat stores.
  2. So you may or may not experience weight loss.

However, keep in mind that as your body initially burns the stored carbs left…

The water that binds them is eliminated through urine or sweat [1].

So the initial shedding of extra pounds you may experience could just be water.

This is also why right after starting Keto, you may feel the need to go to the bathroom more often.

Additionally, you may feel thirsty more frequently.

While losing water weight is good, that does not reflect a loss of fat.

As to how much you should expect, here are a few numbers:

  • people lose anywhere between 1 pound and over 10 pounds in the first week
  • the larger you are, the more water weight you will lose

Still – keep in mind that this likely has nothing to do with fat stores.

Once you are past the adjusting stage and are able to enter ketosis…

You will likely notice a change when it comes to actual fat as well!



#2 – First Week Side Effects

Unfortunately, there are quite a few conundrums you may run into as you are getting used to Keto.

After all, it's all about diminishing the intake of carbs.

Honestly, this is one of the main nutrients in many diets.

In the beginning, you will not feel many benefits – since your body is distracted by all the sudden changes.

Besides, it's too early to be thinking of any significant improvements.

Those usually show up after a few weeks have passed.

1. Mental Cloudiness

As we have assessed, the first week is going to be quite the shock for your body.

Remember that you are essentially trying to get your body to switch energy systems.

That's certainly not something that happens effortlessly.

Once your body depletes the remaining stores of glucose in your body…

You may have to go through a few days that leave you feeling slightly unproductive.

That's because getting your brain to switch from requiring glucose for fuel to burning fat takes time.

Naturally, it may very from person to person, but expect to feel tired more easily as well.

People who have experienced the success of Keto claim that once you power through this stage…

Everything should feel easier afterwards.

Basically, once you get through the first couple of days until you enter ketosis…

You will feel much more energized.

Plus, don't forget to drink plenty of water in the first week!

That way, you avoid feeling dizzy.

2. Cravings

It is usually said of all diets that the very first week is the most challenging one.

Of course, this applies even more if the regimen is particularly strict.

Given that Keto bans the intake of carbs, it's expected to miss them as you transition.

That being said, self-control is the most important trait to have when starting out.

The majority of people rely on carbohydrates for the most part of their diet [2].

In fact, you could even say that carbs and sugar are at the core of many Western diets.

So it should come as no surprise that giving them up suddenly will make you want them more.

After all, it's a nutrient you have been used to for many years.

On top of this, you could also feel slightly irritable while you are dealing with these cravings.

Just know that it's a normal reaction, but it's best to keep yourself grounded.

3. Digestive Issues

Remember what was said earlier about losing your water weight?

Well, this can also result in diarrhea, which you may go through as your body is eliminating excess water.

Once your body adjusts to the changes, your stools will become more and more solid.

However, if this doesn't happen by the time you are in ketosis…

It might mean that you are lacking fiber.

After all, this is a nutrient that contributes to digestive health [3].

However, be sure not to go overboard with the fiber.

On the flip-side, this can lead to constipation.

So it's best to try to maintain some sort of balance.

If you're looking for fiber, be sure to focus on green leafy veggies!



#3 – Long Term Benefits

In truth, the star of the show here is weight loss, naturally.

But let's branch out a bit more – what else can you expect from Keto in terms of positive outcomes?

Well, apparently it offers an array of advantages beyond that.

Let us take a look.

1. Reduced Appetite

It's been proven that committing to low-carb regimes decreases the daily intake of calories [4].

This is handy, given that the main enemy of diets is hunger.

The fact that your appetite slowly dwindles while you get used to it…

Means that you won't have to put up with any temptation to indulge in cheating.

After all, remember that Keto is definitely not the sort of dietary approach that takes kindly to slip-ups.

Therefore, a diet that is high in fat will make things much more bearable in the long run.

2. Boosted Heart Health

This may come as a surprise, but Keto can actually improve the condition of your heart.

A study established that fasting triglycerides were reduced by 24% along with an 18% increase in good cholesterol [5].

Not only that, but blood pressure was also reduced.

This may mean that Keto is a viable diet for people dealing with cardiovascular issues.

If you're one of them, it's in your best interest to also be in good shape.

Perhaps this diet could be the right opportunity for that.

After all, you get two birds with one stone, right?

However, more studies are needed in this sense.

It's best to check in with your doctor before committing to something as serious as Keto!

3. Lower Inflammation Risk

If you didn't know, Keto diet is also very handy for people who often struggle with inflammation [6].

This is a consequence of changing the way your body gets its energy.

Basically, burning ketones in place of glucose is what improves cases of inflammation.

Simultaneously, not dealing with such issues as often also leads to a greater production of energy.

In turn, you will feel more energized.

Not to mention that your body will be more agile in the healing process.

But pay attention if you know you have problems with the level of sugar in your blood.

An imbalance of blood sugar causes many inflammatory issues in the body.

This is especially relevant for people whose bodies rely on sugar for energy.

Therefore – if you suffer from neurological or metabolic disorders, for example…

You might be quite interested in what Keto has to offer in this department.

4. Easier Fat Burning Process

Naturally, it all comes back to this.

After all, I'm sure this is the most relevant advantage of this diet.

To return once again to the topic of weight loss, this remains relevant even well into the regimen.

That's because once you are done with the starting points and the initial water weight…

You should be able to easily enter the famed state of ketosis.

Additionally, research suggests that a high-fat diet such as Keto is more efficient that a low-fat, high-carb diet [7].

Given that being overweight puts you at risk of various diseases…

This benefit obviously cannot be ignored.

Besides, you certainly don't have to stay in ketosis indefinitely.

You can also go for bouts of 4-6 weeks a couple of times per year.



#4 – Long Term Side Effects

This is perhaps the most daunting part of Keto diet.

After all, it's a known fact that it does not go easy on your body.

We have already seen that the beginning stage of Keto is all but friendly.

In other words, you may lose some water weight, but you have to be prepared for the infamous “Keto flu”.

Let's see if things settle down once you are in for the long run…

1. Nutritional Deficiencies

This is likely the most prevalent issue when it comes to Keto.

You already know that this is a very strict diet, right?

Well, if your body was previously used to eating whatever you wished…

Such a shift is going to affect the amount of essential nutrients that you have access to.

That being said, certain food groups are eliminated entirely because of the philosophy of this diet.

Here are a couple of examples:

  • whole grains
  • legumes
  • beans
  • most fruits & vegetables

These food groups are necessary for an all-rounded diet, yet Keto bans them.

You often cannot find the minerals and/or nutrients present in the above examples anywhere else.

As a result, be prepared to deal with many nutritional deficiencies.

Such a problem can develop into other health issues eventually.

This is one of the main reasons why Keto is not recommended for long term.

Because of how restrictive it is, it's simply not sustainable to upkeep for more than a few weeks.

It's a very unbalanced diet – you should not have to abstain from fruits & veggies forever.

2. Muscle Loss

Unfortunately, ketosis doesn't just burn fat.

The longer you stay in this state, the higher the risk of losing muscle tissue as well.

This is further enhanced by the lack of carbs that Keto imposes.

Carbohydrates are needed for proper muscle maintenance.

If that's missing, your body may start to break down your muscle mass along with the fat.

Moreover, remember that your heart is also at risk (because it's also a muscle).

Regardless, you may also struggle to eat an appropriate amount of calories because of how filling fat is.

Because of this, you may be tempted to fast for several hours a day.

Keep in mind that your body needs those calories in order to upkeep the condition of your muscles.

3. Dangerously Low Blood Pressure

It would seem like muscle loss is not the only health risk related to your heart.

If you suffer from high blood pressure and are taking medication, perhaps Keto is not for you.

That's because combined with the treatment you are taking…

Keto could bring your blood pressure to a dangerously low level.

That being said, you should definitely talk with your doctor if you are interested in Keto.

You really want to avoid your blood pressure being too low.

It can even be deadly, so tread carefully.

4. Bad Breath

Compared to other side effects mentioned in this article, this one seems quite mild, right?

While it is true that bad breath does not necessarily impact your well being…

It can make for some awkward social interactions, to say the least.

If you want to avoid this as much as possible, let your peers know you are on Keto.

That way, they know that's what's causing the occasional bad breath you're dealing with.

But let's see why this happens and if you can do anything to prevent it.

While you are in ketosis, your body will eliminate the ketones through various means.

This includes exhalation. When your lungs excrete ketones, you may be left with a foul smell.

Try to drink plenty of water to keep your mouth hydrated and diminish the risk of bad breath.

If that doesn't cut it, there's no shame in trying sugar-free gum or mints!



My Verdict – Is Keto Safe?

Short answer: It's not sustainable in the long run.

The bad far outweighs the good:

  • feeling lightheaded
  • strong cravings
  • diarrhea & constipation
  • having to deal with the Keto flu
  • diminished appetite
  • potentially beneficial for heart health
  • but risky for blood pressure issues
  • less prone to inflammation
  • good weight loss potential
  • many nutritional deficiencies
  • risk of muscle loss
  • bad breath

As you can see, the most significant advantage of Keto is accessible weight loss.

Other than that, it has relatively forgettable perks.

Not to mention that the side effects can have grave repercussions.

That being said, Keto is a very unfriendly diet.

It clearly does not go easy on your body.

If you're still willing to give it a go, it's best to make sure that you are healthy…

And that your only goal is to shed a few extra pounds.

Otherwise, Keto might interfere with other health concerns you are dealing with.

It has the potential to make everything worse, so be very careful.


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Written by 

Sara is passionate about health, beauty and cosmetics. She likes to do research and to find new information about various medical topics. You can connect with her via Linkedin.

Last updated: May 25, 2023

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