Keto Diet Side Effects: Top 7 Complaints

KetoFatFurnace You may experience keto diet side effects when you start the ketogenic way of eating. The good news is that these are temporary but it helps to be prepared for them.

Ketogenic eating is really starting to catch fire which is great news. But if a newcomer to the keto diet has too much trouble up front, they may give up before they are able to reap the wonderful benefits that we all know are coming. Don’t give up! We want you to stick with the ketogenic diet until you experience the remarkable benefits for yourself.

So, let’s talk about the top seven side effects that may cause people to give up on the ketogenic way of eating. Now let us say that the ketogenic diet is a very natural diet. It does not cause any long-term vitamin mineral or nutrient deficiencies. There are some gurus out there who will say that it does and that you should take their supplements which they happen to make money off. That’s not necessary. You don’t need any keto products – just the ketogenic way of eating. None of that other  stuff is necessary to enjoy a rewarding ketogenic way of eating.

But there are possible obstacles and challenges to anyone trying the keto diet for the first time. We want you to be prepared for them so that if and when they occur, you won’t quit and will instead know how to push on through to success.

Follow these suggestions and the transition to the ketogenic way of eating will be relative plain sailing. After a month or so, it will become second nature. So here are the top 7 side-effects facing newcomers to the keto diet – and how to fix them.

Keto Diet Side Effects


This is not really the flu. It’s not contagious at all. The keto flu describes a collection of symptoms experienced by some people when they first start the keto diet. These symptoms, which can feel similar to the flu, are caused by the body adapting to a new diet consisting of very little carbohydrates.

It’s a combination of two things that happen when you start eating a good strict ketogenic diet. It doesn’t mean that the ketogenic diet is bad for you. It just means that your body’s adjusting.


So, there are two things taking place. First of all (a lot of people don’t realise and you may already know this or you may not) we actually have a sort of addiction to sugars and carbs and simple carbohydrates and starches. They actually stimulate the pleasure centers in our brain and stimulate dopamine secretion just like if you were addicted to some narcotic or street drug. You get the same kind of dopamine release when you eat that that bagel or that honey bun or that ice cream cone. That’s why we love it so much and we call it comfort food. You’ve got to break that addiction. You’ve got to break that cycle and that’s going to hurt for a few days.

If an alcoholic is trying to get off alcohol and he’s not feeling well, the last advice we would ever give him is he should take a shot of whiskey. Similarly, it’ll make you feel better short-term to eat carbs and sugar but that doesn’t mean that he should do that. You need to stick with it until you break the sugar,  starch and simple carbohydrate addiction – just like the alcoholic needs to stick with it until he breaks his alcohol addiction. So that’s one reason you may feel bad at the start and the only thing you can do about that is just stick with it that will go away in a few days.


The second thing that happens is, a lot of times when you start the ketogenic way of eating, your body is very inflamed at the beginning. The ketogenic diet is very non-inflaming and so almost immediately the swelling from the inflammation in the various parts of your body will start to go down and that’s a very good thing. You want that. But it also promotes a lot of urination for a few days. A lot of people will lose several pounds of body weight and it’s not fat they’re losing, but they are losing the fluid.

The way your kidneys work is you’re going to pee out a lot of your electrolytes as well sodium, potassium and magnesium. If you’re already borderline deficient in magnesium (as many people are even before they come to keto) then you’re going to have some problems.

The way to fix the keto flu is firstly, stick with it so you get past the sugar and starch addiction. Secondly, you need to replace your electrolytes by eating lots of good unprocessed sea salt and then also you may need lite salt which contains potassium chloride.

These will replace your sodium, your potassium and then if you need some magnesium as well you can take a simple supplement. A lot of people finds this helps them get through the few days of the keto flu – which normally takes just a few days or a couple of weeks. Once you’re over it, you are unlikely to experience keto flu again.

You get all the minerals and vitamins and nutrients you need from the ketogenic diet so you’re not always going to have to supplement those things. That’s just in the first few days or weeks.


Many people are deficient in potassium and magnesium. If that applies to you, when you come to the ketogenic way of eating and you’re getting rid of the inflammatory fluids and peeing out your electrolytes temporarily, then you may have muscle cramps. The quickest and easiest way to fix that is to get a magnesium supplement. You won’t have to do that forever because the ketogenic diets actually very rich in magnesium if you’re eating it properly. But for the first few days you may need that because you’re coming to Keto deficient in magnesium.

The second thing is to again get some lite salt which has potassium chloride. This together with the magnesium will help make the cramps go away. And that also is a short-term problem with the ketogenic diet.


A lot of people complain about constipation for the first few weeks on keto.  There are two things going on. You come to keto from the typical Western diet. You’ve been eating a ton of carbs and your gut is full of carb-loving bacteria. To help restore regularity, you need to increase the amount of keto-loving bacteria in your gut. There are several things you can do to alleviate constipation.


Good-quality probiotics are available from any reputable health food store. You’ll usually find them in the refrigerator. A good probiotic is going to help to balance your gut bacteria and help the constipation go away.


Not only will magnesium help with the “keto flu”, it will also help alleviate constipation. Magnesium citrate tends to loosen up the bowel movements. Always take your magnesium at bedtime because it tends to help you sleep a little bit better, too. You wouldn’t want to take that in the morning and then be sleepy when you could have used that benefit to sleep at night.


Another thing you can take that will help with the constipation is a good quality (hopefully homemade) bone broth. This really helps to calm down the gut and help it adjust to the ketogenic way of eating a lot faster.


Some people don’t get constipation. They get diarrhea/loose stools when they switch to keto and especially someone without a gallbladder or someone who’s had a gastric bypass. They may have a little extra trouble with diarrhea just because they can’t process as much fat as they’re eating. This is temporary. The liver will usually ramp up the bile production and then you’ll be just fine.

Sometimes you will need to back off on the fat for a few days if you have a lot of diarrhea. If this is the case, only increase the fat gradually so that your liver has time to increase the bile production.

Also, again, the probiotics come in very handy if you’re having diarrhea because you’re trying to encourage keto-loving bacteria and eliminate carb-loving bacteria. So a good quality probiotic from a health food store will help that. Also, again bone broth will tend to calm the gut provided it’s real bone broth – not the mass-produced variety full of flavouring and artificial ingredients. That’s not real bone broth. I’m talking about real homemade bone broth and their multiple recipes on the internet that you can google to find out about that.

Now if you have the diarrhoea and you’re already taking a magnesium supplement you may need to decrease the amount of the magnesium supplement because magnesium will tend to loosen your bowel movements.


When you start eating keto, you’re getting rid of all the inflammation in your body. That means peeing extra fluid which contains your sodium, your potassium and magnesium. This can make some people very fatigued and droopy and tired. The way you’re going to fix this is by replacing your electrolytes. This is not a permanent thing with the ketogenic diet.

Most people who’ve been keto for a while will tell you about how much energy they have and so don’t think this fatigue is permanent.

Remember, you won’t have to take supplements forever – just for the first couple of weeks. All you need is a good unprocessed sea salt, a magnesium supplement and a potassium supplement to see you through these keto diet side effects.


This is a rare side-effect but needs to be addressed. You may experience your heat beating really fast or really strongly or beating irregularly. This again is almost certainly related to the shifts in potassium and magnesium that you’re having but it could also be a more worrisome medical thing and we don’t believe the ketogenic diet causes heart problems. The ketogenic diet is very good for your heart in multiple ways but it may uncover a pre-existing heart issue that you aren’t aware of.

And so, if you have palpitations when you start keto, then you need to up your potassium and you need to up your magnesium like we talked about earlier. But you also need to go see your doctor and let them check your heart and make sure that there wasn’t a pre-existing heart condition that your carb addiction and staying high on sugars and starches all day may have masked.


A lot of people – unused to the whole foods found in the ketogenic diet –  find that their bodies rebel. It’s used to eating processed foods, lots of processed carbs and sugar, “What is all this whole food? This green stuff and this meat? I’m not used to this!” and so it can take a while before your gut bacteria get used to eating keto.

You’ve got to get rid of your carb-loving bacteria and get the keto-loving,  meat-loving bacteria built up in your gut so that it will know what to do with this new way of eating. Bloating is a natural symptom of this transition period. The two things that will help with the bloating is just give it time and also take a good-quality probiotic.

We talked about earlier that will help with that a lot and then also a good quality preferably homemade bone broth will also help calm your gut down and help to support the good keto-loving bacteria.

Now that’s the top seven complaints that newcomers to keto often encounter. The ketogenic diet is one of the most nutritionally complete diets available. You will have no vitamin or mineral deficiencies once you have adapted to the ketogenic way of eating. So, don’t think that there are long term deficiencies or problems from this diet. They’re not. Persevere with the keto diet, get over any initial humps and you will be amazed at the rewards waiting on the other side in terms of better health, more energy and dramatic weight loss.


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