How to Get Rid of Keto Fever and the 'Keto Flu'

December 8, 2025 •

4 min read

Approximately 1.5% of the global population follows a ketogenic diet, with many experiencing temporary, flu-like symptoms known as the 'keto flu'. A common sign is feeling unwell, sometimes with a low-grade fever, as the body adapts to burning fat instead of glucose. This article details how to get rid of keto fever, along with other uncomfortable side effects, using simple, actionable strategies.

Quick Summary

The 'keto flu' describes temporary fatigue, headaches, and low-grade fever during the body's adaptation to burning fat for energy. Strategies for relief involve replenishing electrolytes, ensuring hydration, getting adequate rest, and consuming enough healthy fats to support metabolic changes. Gradual dietary changes can help mitigate adverse effects.

Key Points

Replenish Electrolytes: Drink bone broth or use a sugar-free electrolyte supplement to replace lost sodium, potassium, and magnesium, which are major causes of keto flu symptoms.
Stay Hydrated: Drink plenty of water throughout the day. A homemade 'Keto-ade' with water, salt, and a potassium source can be very effective.
Rest Adequately: Allow the body to rest and adapt during the initial transition period, avoiding intense exercise that can worsen fatigue.
Eat Enough Healthy Fats: Do not restrict healthy fats, as they are the body's new primary fuel source and prevent low energy levels.
Start Gradually: Consider easing into the diet by first reducing processed foods, rather than a sudden, drastic cut in carbohydrates.
Mind Your Fiber Intake: Incorporate low-carb vegetables like leafy greens and broccoli to prevent constipation.

Understanding the Root Cause of Keto Fever

Keto fever is a symptom of the body transitioning into ketosis, not a viral infection. When carbohydrate intake is reduced, the body uses stored glycogen. Because glycogen binds to water, this causes rapid water and electrolyte loss, including sodium, potassium, and magnesium. This electrolyte imbalance and the metabolic shift from burning glucose to fat (ketones) lead to flu-like symptoms, including a low-grade fever.

The Critical Role of Electrolytes

Electrolytes are minerals essential for regulating fluid balance, nerve function, and muscle contractions. On a ketogenic diet, insulin levels drop, signaling the kidneys to excrete more sodium and water. This process can quickly deplete electrolyte stores, leading to headaches, muscle cramps, and fatigue. Replenishing these minerals is the most effective step to alleviate keto fever and related symptoms.

Immediate Actions to Counter Keto Flu

Relief for keto fever can often be found by addressing the fundamental changes in the body's chemistry. Implementing key strategies can help improve well-being, often within a few hours.

Increase Electrolyte Intake: Supplementing with electrolytes is one of the fastest ways to feel better. This can be achieved by consuming salty bone broth, drinking water with added pink Himalayan salt, or using a sugar-free electrolyte supplement powder. The aim is to replenish lost sodium, potassium, and magnesium. Foods like avocados, spinach, and nuts also offer natural sources.
Boost Hydration: Simply drinking plain water isn't enough; lost minerals must also be replaced. Drink plenty of water throughout the day. Many keto followers create 'Keto-ade' by mixing water with salt and a potassium source, like cream of tartar. Proper hydration combats symptoms like headaches and fatigue.
Prioritize Rest: The body is working hard to rewire its energy source. Pushing through strenuous workouts can worsen fatigue and stress. For the first week or so, choose lighter activities such as walking or yoga and ensure adequate sleep to aid recovery.

Strategies for a Smoother Keto Transition

A long-term approach to managing the diet can prevent keto fever from returning. Mindful changes to daily habits can lead to a more comfortable transition into ketosis.

Eat Enough Healthy Fats: Don't restrict fats. A common mistake is restricting both carbs and fats, which can worsen keto flu symptoms. Healthy fats like avocado, nuts, olive oil, and fatty fish are essential for sustained energy on a ketogenic diet.
Include Fibrous Vegetables: Constipation can result from eliminating fiber-rich grains and fruits. Incorporate low-carb, high-fiber vegetables such as spinach, broccoli, and cauliflower to support digestive health.
Consider a Gradual Start: An abrupt transition to a very low-carb diet can be a shock. Ease into the diet by first cutting out processed foods and sugary drinks, then gradually reducing starchy carbohydrates over a week or two. This gentler approach can minimize symptoms.

Comparison of Common Keto Flu Remedies


Remedy	Primary Benefit	Who is it for?	Considerations
Electrolyte Supplements	Replenishes lost minerals directly and quickly.	All keto beginners, especially those with severe symptoms.	Choose sugar-free options; may cause digestive upset if overused.
Bone Broth	Provides sodium, potassium, and trace minerals in a nourishing liquid form.	Anyone seeking a natural, soothing food-based remedy.	Ensure the broth is low-sodium if making your own; store-bought can be high in salt.
Homemade 'Keto-Ade'	Cost-effective and customizable way to get electrolytes and hydration.	DIY enthusiasts who want to control ingredients.	Requires self-measuring and proper ratio of salt, potassium, etc.
Increased Healthy Fats	Provides a steady energy source, reducing fatigue and cravings.	All keto dieters, especially those feeling low on energy.	Needs to be balanced and from healthy sources like avocado, not just dairy.
Increased Rest	Supports the body’s metabolic adjustment without added stress.	All keto beginners struggling with fatigue.	May not be practical for everyone’s lifestyle, but important to prioritize.

Long-Term Maintenance and When to See a Doctor

Maintaining electrolyte balance and hydration remains important after the initial transition. The body's needs are different when in ketosis, and consistent replenishment is key, especially for active individuals. Most keto flu symptoms resolve within one to two weeks as the body becomes 'fat-adapted'. If symptoms persist, worsen, or include a high fever, prolonged diarrhea or vomiting, consult a healthcare professional to rule out other medical issues. A registered dietitian can also provide guidance on creating a nutritionally sound keto meal plan.

Conclusion: Navigating the Transition to Feel Better

Keto fever and flu-like symptoms are a common but temporary part of nutritional ketosis. Understanding that these symptoms result from electrolyte imbalance and dehydration allows for direct action to address the causes. Focus on electrolyte replenishment through supplements or mineral-rich foods like bone broth, prioritize hydration, and allow adequate rest. A gradual diet transition, with a focus on healthy fats and fiber, can make the process smoother. Listen to your body and seek professional medical advice if symptoms are severe or persistent. With the right strategy, the keto flu can be overcome to enjoy the benefits of a ketogenic lifestyle without significant discomfort. For further guidance, see resources such as the Ketogenic Diet resource from Harvard's School of Public Health, which provides expert dietary reviews and information. Harvard T.H. Chan School of Public Health: The Nutrition Source

Frequently Asked Questions

Keto fever is a collection of flu-like symptoms, including a low-grade temperature, that can occur when starting a ketogenic diet, rather than a true fever. It happens as the body shifts from burning carbohydrates for fuel to burning fat (ketosis), leading to dehydration and electrolyte imbalance due to rapid water loss.

For most, keto flu symptoms are temporary, lasting only a few days. However, for some, they may persist for up to a couple of weeks. The duration depends on factors like previous diet, overall health, and how consistently electrolytes and hydration are managed during the transition.

The most effective and fastest methods include drinking plenty of water, consuming mineral-rich bone broth or an electrolyte supplement to replace lost sodium and potassium, and getting plenty of rest. Increasing healthy fat intake can also provide the body with needed energy.

While complete prevention is not always possible, the severity and duration of keto fever can be significantly reduced. Easing into the diet gradually, ensuring ample hydration and electrolyte intake from day one, and avoiding physical overexertion are key preventive measures.

It is generally advised to avoid strenuous exercise when experiencing keto flu symptoms. Strenuous activity can worsen fatigue and dehydration. Instead, opt for light exercise like walking, stretching, or yoga, and save high-intensity workouts until the body has fully adapted.

Electrolytes can be increased through diet by consuming plenty of sodium (salt your food), potassium (avocados, spinach, mushrooms), and magnesium (leafy greens, nuts, seeds). Sipping on homemade bone broth is also an excellent, natural way to replenish minerals.

Consult a doctor if symptoms are severe, include a high fever, or last for more than a couple of weeks. This is important to rule out any other underlying medical conditions that might be mimicking keto flu symptoms.