The Keto Flu Relief Guide

Search the Blog

“Why do I feel out of it?”

You may have heard about the wonders of the ketogenic diet. People have experienced weight loss and altered their eating habits for the better, even cooking for the first time ever.

But the keto diet has challenges. Some are mental, others are physical.

There’s one challenge that awaits all keto practitioners: the dreaded keto flu.

How keto flu affects the body differs per individual, but it’s the greatest threat to your progress on the keto diet. Your temptation to abandon the keto diet rises when it strikes. It’s disruptive to your daily activities. And annoying.

The good news is that once you’re finished with keto flu, the symptoms usually never return.

What are ways to combat symptoms of keto flu? Is it possible to experience relief faster? What is the timeline of keto flu effects? Read the FAQ below to browse common problems that keto practitioners face with keto flu.

Common FAQs About Keto Flu

Keto flu, also known as carb flu, is a common problem when starting the diet. The body adapting to a reduction in carbohydrate intake and other dietary changes can result in a range of temporary side effects. Below are examples of some of the symptoms, why they happen, and how to relieve them.

Common symptoms

Some individuals make the switch without experiencing any problems. Others may experience some of the following symptoms:

  • runny nose
  • sore throat
  • coughing and phlegm
  • chills or fever
  • aches
  • nausea, vomiting
  • brain fog
  • depression, anxiety, lack of motivation
  • insomnia

For many people, keto flu symptoms resolve pretty quickly on their own. However, they can be disruptive to work, socialization and other important activities. Luckily, there are plenty of ways to alleviate or reduce these problems.

Drink enough water

Without as many carbs, the body will burn through its glycogen stores, or stored sugars, more rapidly. These stores reside in water in your muscles, which means water also gets depleted. This can result in a sore throat, nausea, fatigue, vomiting and other symptoms.

Symptoms like vomiting cause water loss and can lead to further dehydration. Make sure to drink enough water, more than usual, to replace the fluids lost by transitioning to a ketogenic state.

Increase electrolyte intake

Due to the loss of water weight, essential electrolytes such as magnesium and potassium are more easily flushed out of the body. This leads to an electrolyte imbalance, which can have side effects like muscle cramps and aches, irregular heartbeat, joint pain, chronic fatigue, and even insomnia.

Fortunately, it’s easy to increase electrolyte intake. In addition to eating certain whole foods (celery and cucumbers, for example) and drinking keto-friendly liquids like bone broth, electrolyte supplements can help replenish them.

Slowly cut back on carbs

It may be tempting to dive headlong into the keto diet to reap its many benefits, but this can be a huge pitfall. People who are eager to get into ketosis fast might think it’s a good idea to immediately cut out all carbs. However, this can have neurological side effects, including brain fog, irritability, anxiety, and depression.

Cutting carbs down by 25-50 grams per week is an easier way to stick to the diet, fight any initial sugar cravings, and keeping mental moods in check.

Take exogenous ketones

The transition to metabolizing fat for fuel can be the driver of some keto flu’s worst symptoms. When the body is used to running on carbs, initially it doesn’t produce enough ketones to function at its best.

Many people supplement with exogenous ketones, meaning ones sourced from outside the body. Supplements usually come in the form of a powder or ester. Some find that this completely eliminates their keto flu symptoms and helps them become fat-adapted in a short period of time.

When you start the keto diet to activate ketosis, you’re likely to experience benefits. But because of keto flu, you can feel worse before achieving the benefits of a ketogenic diet. It’s helpful to know the duration of symptoms that are associated with keto flu and when they can appear.

The Keto Flu Timeline

Timeline of keto flu symptoms
Show this image on your web page:
<a href="" target="_blank" rel="noreferrer noopener nofollow"><img src="" alt="Timeline of keto flu symptoms" /></a>

Genetics, age, health, habits, and other individual factors affect the intensity of symptoms at different amounts of time. Take a look at this average timeline for the keto flu.

The Beginning: 1-3 Days

Keto flu usually kicks in by day three of the diet. You begin to feel more sluggish, tired, and cranky. Nausea, light-headedness, and headaches are common symptoms. You may also have cravings for those carbs you’re missing and you’ll feel “off.”

About Half-Way Through: 4-5 Days

You’ll likely start experiencing more flu-like symptoms by day five. Because your body is working hard towards ketosis, dehydration and mineral loss causes headaches and muscle fatigue. Some people also experience constipation and stomach cramps, with or without diarrhea. You also have the same symptoms from the beginning as well.

Almost Over Keto Flu: 6-7 Days

By day seven, the symptoms will start disappearing but you’ll probably continue to feel sluggish. As your body approaches the state of ketosis, you’ll start to feel normal and the worst symptoms will be gone.

The End: 8-12 Days

At the end of the keto flu, you’ll feel like a new person. Your body will continue adjusting but without the experiences of flu-like symptoms. Your energy will return, sleep becomes better, and carb cravings are non-existent.

Ways to Shorten the Keto Flu

You can help your body adjust better to the keto diet and shorten the length of time you experience the keto flu. In most cases, it’s about tackling the symptoms directly.

  • Make sure you’re getting enough sleep.
  • Help your body activate ketosis faster by trying intermittent fasting. You also might need to eat more fat.
  • Adjust your carb intake based on your needs. Cutting carbohydrates too fast can make symptoms worse, so it’s okay to ease into the keto diet.
  • Drink plenty of water. You’re more likely to experience dehydration during the first few weeks of the diet.
  • Combat cramping by increasing your fiber intake. If you experience diarrhea and stomach cramps, fiber can help bulk up your stool and decrease the frequency of diarrhea.
  • Because your body excretes minerals more quickly during the beginning of the keto diet, you’ll need to replenish them with electrolyte supplements or keto-friendly electrolyte drinks.
  • Change your exercise routine a bit. It’s okay to exercise, but avoid strenuous activity and let your body rest when you’re experiencing the worst symptoms.

Once you’ve survived keto flu, you’ll feel proud of your perseverance. Many people think something is wrong and don’t understand the process your body undergoes to adapt to the keto diet. Hang in there and use these tips to experience keto flu relief faster.

The keto diet has many benefits but it also has received some criticism. The most discussed downside of the keto diet is “keto flu.” One side effect that doesn’t receive much attention is joint pains caused by the keto diet.

Why Do Joint Pains Happen on the Keto Diet?

Individuals on a keto diet usually eat a lot of protein but oftentimes consume less calcium. Plus, the ratio of animal and vegetable protein can be uneven. Both of these factors can cause a loss of bone density, which can lead to joint pain. If an individual follows the keto diet over a long period, they increase their risk for osteoporosis.

First, the elimination of fruits, grains, and most vegetables due to the diet results in the body failing to receive proper vitamins and minerals. Since meat is high in protein and some vitamins, it doesn’t include everything the human body needs to function efficiently. This causes undue strain and leads to painful flare-ups in the joints.

Second, high amounts of saturated fats increase the chances of joint pain. Individuals following the diet can avoid inflammation by incorporating good fats from foods such as salmon or avocados, and consume fewer foods like red meats, which are high in cytokines and leukotrienes that escalate inflammation.

How Long Do Joint Pains Last?

Many individuals report reduced inflammation and joint pain on the keto diet. For that reason, an increase in joint pain can simply be a symptom of the keto flu. The keto flu typically starts after a few days and occurs in the early stages of the diet. The general recommendation is to wait for the joint pain to subside after the keto flu passes.

Where Do Joint Pains Usually Occur?

Joint pains caused by the keto flu are commonly reported in the knees, but the impacted areas vary. A person with a previous history of inflammation and irritation is more likely to experience joint pains.

How Can Individuals Relieve Joint Pain Symptoms?

If the keto flu passes, and individuals still experience joint pain, it doesn’t mean they need to stop following the diet. Instead, it’s a sign that they should incorporate more low-inflammation foods into their diet (keto-friendly of course). The top seven anti-inflammatory foods for a keto diet are turmeric, ginger root, salmon, macadamia nuts, walnuts, healthy nuts, and green, leafy vegetables.

Joint pain is not an indication of failure. Like any diet, the keto diet takes tweaking and modification to make it a perfect fit. First, determine if the joint pain is just a symptom of keto flu. If joint pains continue after the keto flu passes, the next step is to try altering the diet to include more anti-inflammatory foods. Finally, if joint pains persist then you should consult with a medical professional or consider abandoning the diet.

Why Keto Flu Happens

Keto flu occurs when the body undergoes a massive metabolic shift. The reduction of carbohydrates drains the body’s glycogen stores and forces it to switch from carbs to stored fats for fuel. The adaption causes insulin levels to drop, the release of ketones, and kidneys to work more than usual

All the actions above lead to dehydration and loss of electrolytes.

Low energy and “brain fog” are common keto flu symptoms. Some people also experience digestive issues when shifting from the consumption of starchy vegetables and grains. These symptoms are usually short-term, lasting from a few days until a couple of weeks.

Drinking liquids can simultaneously solve two problems: thirst and electrolyte replenishment. Read the list below to learn about keto-friendly drinks that can alleviate keto flu symptoms.

Best Drinks for Keto flu Relief


Water is no-carb, chemical-free, and when salt is added—acts as an electrolyte replenisher. It’s best to drink it throughout the day to remain hydrated. 

Sparkling Water (Seltzer Water)

It has up to 5 calories, even for slightly flavored varieties. The carb-free drink provides a great alternative to tonic water (clear and bubbled water that contains a lot of sugar). A dash of squeezed lemon adds approximately ½ gram of sugar.

Hard Liquor

You can drink alcohol on keto, but there are ramifications to consider. Keto dieters should limit themselves to one glass of wine if possible (unless a wine’s serving size is keto-friendly). Dry wines such as white wine have less sugar and carbs than other types. Rum, vodka, gin, and whiskey without sweetened mixers have 0g of carbs. For a nice chaser, mix them with keto-friendly sparkling water

Diet Soda

Even though some experts advice against diet soda, some products are fine for keto because they’re sweetened with sugar alcohol. Diet soda is not the best pick because they can contain a high amount of carbohydrates, plus most of them still considered empty calories. If you’re thirsty and in a jam, consider drinking a diet soda (use our food label calculator to determine if a drink is keto-friendly).


A plain cup of coffee is keto-friendly and alleviates “brain fog.” Extras that are added to coffee determines whether the drink stays keto-friendly or not. Pouring unsweetened cream or a few packets of sweeteners (aka “sugar substitutes”) won’t kick you out of ketosis. Most keto dieters prefer to add fat that comes with heavy cream. However, too much coffee detracts from hydration and leads to thirst. Drink sparingly.

Nut Milk

Nut milk is low-carb and nutritious, perfect for the keto diet. Unsweetened almond, cashew, and coconut milk form 1g of carbs in a single serving (1-2 cups). They’re also a great source of vitamins and minerals, especially sodium and potassium, which are necessary for hydration and electrolyte replenishment.

Bone Broth

Bone broth is a comfort drink that replenishes electrolytes. It creates a savory tasting experience when it’s steamed. Most bone broths have zero carbs, contains less than 50 calories, and averages around 9g of proteins. 

Calorie Free Tea

Most teas are thirst quenchers. They’re low-carb and free from calories—if you don’t add sugar. Sweeteners are fine to use if they’re also low in carbs. Teas promote antioxidant flavonoids and improve the function of the blood vessels. Green tea is infamous for increasing your metabolism.

Dairy Milk

You can drink dairy milk, but check its food label to make sure it’s keto-friendly. Pick whole milk for high-fat content and pay very close attention to the serving size. One cup can contain 12 grams of carbs, which would consume half of some dieters’ daily carbohydrate allowance.

Gatorade Zero

Researchers have long suggested that Gatorade is a healthy option for electrolyte recovery. Because regular Gatorade varieties contain a lot of sugar, they’ve recommended that only individuals who workout for more than 90 minutes per day consume the drink. Since their new ZERO series contains 0g of sugar, relying on sucralose instead, this makes the drink keto-friendly.

Like many diets, the keto diet often requires a person’s body to adjust to unfamiliar changes. Trying the diet for the first time could result in keto flu. New keto dieters should watch out for several symptoms and explore supplement options to help them get through its early stages.

What is Keto Flu?

Keto flu, also known as carb flu, is a condition that people starting the keto diet experience due to drastic changes in their eating habits. The symptoms of this condition are similar to those of the regular flu, including the following:

  • Vomiting
  • Irritability
  • Stomach pain
  • Sugar cravings
  • Poor concentration
  • Constipation
  • Muscle cramps
  • Difficulty sleeping
  • Dizziness
  • Nausea
  • Mood swings

What Causes Keto Flu?

Keto flu occurs due to the decrease of insulin in the body, a process that forces a person’s kidneys into overdrive. Digestive issues, low energy, and brain fog can crop up as a result of the switch from high-carb to high-fat foods.

Some symptoms resolve more quickly than others. Keto flu can last a minimum of three days or a maximum of two weeks.

Best Supplements for Keto Flu Relief

Perfect Keto Electrolytes

Perfect Keto Electrolytes supplements are convenient, well-absorbed capsules that contain calcium, magnesium, potassium, and sodium — four electrolytes essential for keto.

Benefits include:

  • Zero carbs
  • No artificial ingredients or fillers
  • Easy-to-ingest capsule form
  • Better electrolyte balance and hydration
  • Improved sleep quality

These supplements can be effective during keto flu for sleep issues, nausea, dizziness, stomach cramps, and dehydration.

Zeal Naturals Maximum Electrolytes

Zeal Naturals Maximum Keto Electrolytes bottle

Zeal Naturals Maximum Keto Electrolytes supplements are made from real salt, B-Vitamins, potassium chloride powder, magnesium, and zinc to restore depleted vitamins and minerals.

Benefits include:

  • Gluten-free
  • GMO-free
  • Made in the US

People suffering from dehydration and muscle cramps can benefit from taking these supplements before performing intense physical or mental activities.

Keto Function Electrolytes Trace Minerals

Keto Function electrolyte supplements bottle

Keto Function electrolyte supplements contain high amounts of Vitamin D, magnesium, calcium, sodium, trace minerals and chloride to keep the body functioning optimally.

Benefits include:

  • No fillers
  • Boosted energy and stamina
  • Improved bone, joint and digestive health

People with low energy and stomach pains can take these supplements with meals, especially early in the morning, to stave off keto flu symptoms.

Keto-Vitals Electrolyte Capsules

Keto Vitals electrolyte capsules bottle

Keto-Vitals electrolyte capsules are made with essential electrolytes, including magnesium, calcium, sodium, and potassium, to help balance the body while on the keto diet.

Benefits include:

  • Increased energy levels
  • Improved mood
  • Better sleep quality

Keto dieters can take these capsules at any time to reduce the severity of brain fog and concentration issues.

Euphoria Nutrition Keto Ultra-Premium

Euphoria nutrition ultra-premium capsules bottle

Euphoria Nutrition Ultra-Premium keto pills are twice-a-day supplements that can help control appetite.

Benefits include

  • 100% gluten-free
  • Boosted metabolism
  • Better weight management

Taken as directed, these keto pills can help keep sugar cravings to a minimum.

Approved Science Keto Electrolytes & Ketones

Approved Science keto supplement electrolytes and ketones capsules bottle

Approved Science Keto supplements combine four types of ketones, MCT oil, and other potent ingredients to help people get into and stay in ketosis.

Benefits include:

  • 100% natural ingredients
  • Essential electrolytes
  • Improved blood sugar levels
  • Faster ketosis

These supplements are for people who want their keto flu symptoms resolved as quickly as possible. Taking them before symptoms arise could put a damper on the keto flu.

Nuwellix Keto-5 Electrolytes

Nuwellix Keto-5 electrolyte supplements capsules bottle

Nuwellix Keto-5 supplements are a natural blend of vitamins and minerals to help users achieve ketosis.

Benefits include:

  • Faster ketosis
  • Boosted metabolism
  • Improved ability to burn fat
  • Appetite control

These easy-to-swallow capsules can be taken before, during or after the onset of symptoms. 

The use of exogenous ketones is controversial. Some experts believe they help the body enter ketosis faster and alleviate keto flu symptoms. However, others claim they’re useless and that the only important ketones are the ones produced by the body. We explore this topic to showcase the usefulness of exogenous ketones and whether they’re worth the cost of being a keto diet supplement.

What are Exogenous Ketones?

Ketones are small molecules that are used as fuel when blood sugar is running low. Most of the time, they’re produced naturally in the liver. However, scientists have discovered a way to administer ketones to help reach and maintain ketosis.

Ketone supplements contain only the beta-hydroxybutyrate ketone, as the other primary ketone body, acetoacetate, isn’t chemically stable enough to be used as a supplement. Raspberry ketones, which are derived from a chemical in red raspberries, are less popular due to their questionable efficacy.

Exogenous ketone supplements cause blood ketone levels to increase slightly, even if a person’s body isn’t in nutritional ketosis. This increase can provide some of the benefits of ketosis such as improved concentration and energy levels.

The Different Types of Exogenous Ketones

Exogenous ketones are available in two common forms: salts and esters.

Ketone salts are made by binding ketone bodies to mineral salts, such as sodium, potassium, or calcium. These salts are usually sold in powder form and are mixed with a liquid before they are taken.

Ketone esters, on the other hand, contain ketone bodies bound to alcohol molecules. Individuals can consume a greater amount of esters than salts, making them more effective for increasing ketone levels. They’re mainly available in liquid form and available for purchase at

Most manufacturers of exogenous ketone supplements recommend taking a dose every two to three hours, and they can be taken with or without food. Ketone esters are known to taste terrible, although many companies have created flavored products to make consumption more tolerable.

Risks of Taking Exogenous Ketones

There are no reports of death linked to the consumption of exogenous ketones. The side effects are mild and include nausea, diarrhea, and stomach discomfort. Some consumers report higher levels of gut distress from ketone esters.

It’s safe to perform normal activities, including exercise, while taking exogenous ketones. However, individuals should still be wary of their requirements for traditional fuel sources, i.e., carbohydrates, fat, and protein.

What Do Experts Have to Say?

Some researchers suggest that using exogenous ketones can be beneficial. A 2017 study concludes that “exogenous ketone drinks are a practical, efficacious way to achieve ketosis.” It observes that ketone esters raise ketone levels in the blood more than ketone salts; more ketone salt consumption was necessary to achieve ketosis. This study also notes how recovery times improve with the ingestion of ketone esters. Researchers simulating the conditions of the Tour find that athletes using exogenous ketones experience a 15% improvement in recovery and produce more power at a higher sustainable pace (Gear Patrol).

However, other scientists are less enthusiastic about the effects of exogenous ketones. While it’s widely agreed that exogenous ketones effectively suppress hunger, the fat-burning effects are debatable. Data published in recent years suggests that despite the body breaking down fat to create ketones, it still needs to prevent ketoacidosis, a state of dangerously high ketone levels. To do this, the body limits the breakdown of fat, in turn limiting the production of ketones.

Additionally, exogenous ketone supplements are expensive compared to supplements such as caffeine and creatine, which have been scientifically proven to provide individuals with better short- and long-term performance and body composition benefits.

Are Exogenous Ketones Worth It?

While how much of a benefit exogenous ketones provide is up for debate, many people report using them successfully. Those having trouble getting into or remaining in ketosis on diet alone may find them beneficial. More goal-oriented individuals, such as athletes, might benefit more from other supplements if they’re seeking performance, but might benefit by more rapid recovery. Keto dieters should assess whether adding these supplements fits with their financial, fitness, and overall health needs because they’re not a necessity for achieving success with the keto diet.


It’s easy to focus on maximizing fat and protein intake while decreasing carbohydrate consumption, but some problems happening during keto flu is a result of micronutrient deficiency. Or otherwise, the lack of important vitamins and minerals that help the body function properly. These elements include:

  • Magnesium
  • Heme Iron
  • Sodium
  • Potassium
  • Vitamin K

To learn more about them, including how much to consume daily, you can read our blog post about important vitamins and minerals for the keto diet.