Learn All About the Keto Flu and the Health Impacts of a Keto Diet

keto flu

The keto diet is enjoying immense popularity at the moment, and it’s not hard to see why. The diet makes the appealing promise of being able to lose weight on top of enjoying other benefits that could help combat some serious illnesses while still being able to gorge on many of the most flavorful food items.

Sure, having to severely cut down on your pasta and rice consumption is going to be a big adjustment, but it’s still fun to follow a diet that does not dissuade you from enjoying steak, bacon, and all those other delicious, meaty goodies.

However, the keto diet is not without its flaws. Just like many of the other diets that encourage you to cut out specific food groups while focusing on others have brought their own positives and negatives to the table, the same can also be said for the keto diet.

Included below are some of the currently known side effects of the keto diet, and we’ll discuss how much they should concern you and what things you can do to minimize their impact on your body should you indeed decide to adhere to this new way of eating.

keto flu

What Is the Keto Flu?

One of the most commonly known side effects of the keto diet is the aptly named keto flu.

So what is it?

According to Diet Doctor, the keto flu is basically what happens when your body starts to realize that there’s been a big change in how things work. If you haven’t been following any particular diet up to now or have just been a typical person who consumes carbohydrate-rich foods like grains and sweet treats every now and then, then that means your body has likely relied mostly on sugars for your daily energy needs.

Going on the keto diet forces your body to switch energy sources. Instead of breaking down sugars for energy, your body is now relying on the fat that is in your system.

As you might imagine, your body starting to work in such a different way will impact you significantly. Your insulin level goes down, which Diet Doctor points out is healthy, and the fat stored in your body is now being transformed into energy-providing ketones.

It’s not like you can warn your body about all these coming changes, so they can all hit at once, and your organs may be left wondering what the heck is going on. These changes will also eventually lead to your body expelling more water and sodium to mitigate the insulin drop. It is during this time when you might suddenly start to feel the effects of the aforementioned flu.

The Known Symptoms of the Flu According to Diet Doctor:

Dizziness – Expelling significant amounts of water and sodium from your body over a short amount of time is bound to get you feeling dizzy, so be mindful of that and try to get rest when you can.

Fatigue – You can also expect to feel quite tired when you’re just starting the keto diet, which is to be expected given that your body is still familiarizing itself with a new source of energy and is still trying to adjust accordingly.

Headache – You can probably take some medicine to relieve any a headache you may get as a result of the flu, or you can also rest up and wait until it subsides.

Inability to focus – You’re already feeling dizzy, so it probably won’t come as a shock that trying to focus on something will prove troublesome when you have the flu as well.

Irritability – Your body going through such a big change is undoubtedly going to affect your mood in some way. It may be best to advise your friends and family about that beforehand or just steer clear of them for a bit.

Muscle cramps – Once again, this is something brought about by the sudden loss of excess water and sodium in your system. The cramps could prove quite inconvenient and even painful, so be prepared.

Nausea – Given all the other things mentioned above, you probably could’ve guessed this one was coming too. The nausea may be more difficult to deal with, which is why it’s advisable to avoid those really tiresome tasks when you’re starting the keto diet.

Sugar cravings – This one should not surprise you at all. If you’ve been eating pasta, grains, and other food items full of carbs your entire life, your body is not just going to forget about that all of a sudden. Be strong though, because following the keto diet means steering clear of those types of food as much as possible.

What You Can Do to Fight the Symptoms of the Flu

Wait – This is going to prove to be a challenge given some of the symptoms outlined above, but really, your best course of action for dealing with the diet-induced flu is to rest and wait for it to pass. The flu is expected to last for only a few days, so if you can avoid straining yourself too much within that period of time, that would be ideal.

Get some water and salt back in your body – As Diet Doctor points out, many of the flu symptoms you are dealing with have been caused by plenty of water and sodium exiting your body. Unsurprisingly, those symptoms can be made less impactful by getting more water and sodium back into your body. Upping your water intake is always advisable any way, and as for the sodium, you can reintroduce that to your body via meals if you so choose. Tweak the salt levels of the dishes you are eating just a bit. That should be enough to balance out the sodium that was drawn out of your body. Also, once the symptoms have worn off, make sure to normalize your salt intake again.

Ease into the keto diet – If you tried going on the keto diet before and found that some of the effects of the flu were too overwhelming, there’s a decent chance your body just couldn’t handle everything that was changing all at once. So, before you start the diet again, plan a gradual shift of your eating habits as opposed to just dropping carbs cold turkey. Start by cutting down on the carbs you consume at least a few weeks before your target start date for the diet. Gradually drop more carbs as the days go by, and when the time comes for to properly start the diet, you should be used to not having that much carbs and can transition easily to not consuming them entirely.

Now that you have an idea of how to deal with the flu that can sometimes go along with the keto diet, it’s time to focus on the other side effects of this particular approach to eating.

keto flu

What Are the Side-Effects of a Keto Diet?

The Weight Loss Could Prove Temporary

If you’re a fan of MMA or boxing, you’ve probably heard about the process of cutting weight and how that often involves the fighters expelling as much water from their bodies as they can to meet the upper limit of the weight class they are fighting in. It’s a drastic method designed to get fighters to where they need to be weight-wise, but more often than not, its effects prove temporary. After the fighter makes weight, he/she will likely drink again and end up looking noticeably bigger on fight night compared to how he/she appeared on weigh-in day.

In a way, the initial weight loss that comes with following the keto diet acts similarly to that weight-cutting process. Your weight may tick back up again after you up your water intake, but you should still a net loss in weight.

According to Prevention.com, there’s not a ton of research looking into whether the weight loss that comes from the keto diet can be sustained long-term. Part of that may be because people find it incredibly difficult to just eliminate carbs from their diet, and so the keto principles aren’t followed correctly.

The solution:

It’s simple, if you’re going to start the keto diet, you have to commit to sticking to it. Unlike many other diets where there’s some leeway for you to keep consuming all kinds of food, the keto diet hinges on the body choosing to break down the fat instead of the sugar that is in your system. Should sugar continue to be abundant in your system, your body may not make the decision to start burning the fat instead and no weight loss may take place. It’s going to be a challenge, but commit as much you can if you want a real chance at succeeding with this diet.

Constipation Is Something You’ll Need to Handle

As it turns out, many of the carbohydrate-rich foods people consume regularly also contain the fiber that helps your digestive system stay on track. By staying away from those carbs, you’re also inadvertently steering clear of fiber.

Because of that, you may experience some trouble trying to expel your waste as normal, and that may cause you to become uncomfortable quite quickly.

The solution:

Always keep in mind that the keto diet is only focused on eliminating the carbohydrates in your diet. Getting rid of your regular fiber intake is not its intent. To make up for the drop in your fiber intake caused by no longer eating certain food items, make it a priority to regularly eat other fiber-rich consumables.

The aforementioned article from Prevention.com notes that avocados and nuts contain plenty of fiber, so make sure to integrate them into your revised diet. Try to prepare meals where those food items are used and soon enough, the constipation issues you previously faced should go away.

You’ll Need to Quench Your Thirst More Often Than You Used to

This is another side effect caused by the fact that your body is expelling plenty of water when you first start the keto diet. This one isn’t quite as inconvenient or bothersome as the ones already mentioned, but it is still something you’ll want to pay attention to.

The solution:

Keep a water bottle handy and don’t be afraid to down as much H20 as you need to keep your thirst at bay. Also, if you know that you will be in a situation where drinking water as often as you’d like will not be an option, try to avoid engaging in too much physical activity to ensure that no excess water leaves your body via sweating.

keto flu effects

Hepatic Steatosis

Now, it’s time to focus on some of the more serious side effects that can come from the keto diet. According to an article that can be seen on StatPearls.com that was also cited by the National Center for Biotechnology Information, hepatic steatosis is an adverse effect of the keto diet.

For those wondering what hepatic steatosis, they may know by its more common name: fatty liver.

Healthline notes that fatty liver is a condition that may be caused by the body producing too much fat, or the fat not being metabolized properly. When those things happen, the fat cells just end up in the liver where they can cause different kinds of issues.

At first, the effects of a fatty liver may only manifest as fatigue, abdominal pain, or loss of appetite, but if left untreated, it can lead to the organ failure and from there, the problems will only get more serious and potentially life-threatening.

The solution:

Because you’re already watching your carb and sugar intake, the likely cause for fatty liver in keto diet followers may be the consumption of too much saturated fat. The moment you start experiencing issues with your liver, it will be best for you to keep closer tabs on the kinds of fats you consume and also ask your doctor about continuing the diet.

Issues with Your Kidneys May Pop Up

Eating meat is certainly a big part of the keto diet, but going too heavy on that type of food could put a huge burden on your kidneys. Needless to say, if your kidneys start having issues, you will run into some problems as well.

Kidney stones may even be in your future if you don’t do something to nip those issues in the bud right away.

The solution:

Don’t get crazy with your meat consumption and save room for the other food items included in the keto diet such as low-carb vegetables. To keep your fat intake where it needs to be, use healthy oils for salad dressing to give those vegetables some extra flavor.


Oddly enough, even though you’re eating meat all the time, hypoproteinemia is one of the negative side-effects that can be brought about by going on the keto diet. Hypoproteinemia could be caused in part by your liver and kidneys not being completely healthy.

If you are suffering from hypoproteinemia, it will be best for you to remedy the problem right away. Healthline points out that some of the issues you may encounter from a bout with hypoproteinemia may include muscle loss, plus your heart, lungs, and the immune system is significantly weakened.

keto flu

The solution:

Make sure to get plenty of protein in your diet, but because the hypoproteinemia may be related in some way to issues with your liver and kidney, you may have to get protein into your body in a way other than consuming heaping amounts of meat.

What you can do here is to consume other good sources of protein such as dairy and nuts. If the hypoproteinemia persists, don’t hesitate to seek medical intervention.

Vitamin D and Calcium Deficiencies

Due to you removing certain food items from your daily diet, you may also end up lacking certain vitamins and nutrients. For keto diet followers, vitamin D and calcium may be among those they lack the most, according to Self.com.

When you lack both vitamin D and calcium, your bones may grow weaker over time, which puts you at risk for diseases such as osteoporosis.

The solution:

The good news for you, faithful keto diet follower, is that vitamin D and calcium are not hard to find. WebMD points out that vitamin D can be found in fatty fish like salmon and tuna, as well as cheese and even egg yolks. Luckily, all those food items are good for consumption in the keto diet.

Meanwhile, calcium can be found in salmon too as well as other fishes like sardines, so be sure to include those in your diet.

A Few Final Tips for People Going on the Keto Diet

Though there are different side effects linked to it, the keto diet has been observed as something that can be very beneficial to people. Still, it won’t hurt to consult your doctor before going all-in on it just to make sure you won’t run into unexpected issues.

Continue to keep balance in mind with your food intake even though you are now avoiding carbohydrates.

Don’t forget to drink plenty of water.

Address any health issues that may emerge right away and don’t let them get any worse than they need to be.

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