Keto Workouts: Why You Feel Sick And How To Prevent It

The ketogenic diet is a popular method for weight loss, but it can also cause some minor issues. Many people report experiencing keto flu after starting the diet, with symptoms such as nausea, constipation, headaches, fatigue, and sugar cravings. This is due to the body's response to a sudden reduction in carbohydrates, which are its main source of energy. The high-fat content of the keto diet can also cause nausea as fat takes longer to digest and absorb. Additionally, irregular meal timing and smaller portion sizes can contribute to nausea. While the keto diet may lead to weight loss, it is important to be aware of potential side effects and make adjustments as needed.

Keto flu

The keto flu is a collection of symptoms that some people experience when starting a ketogenic diet. It is important to note that keto flu is not an actual flu, and you will not develop a fever. The symptoms are caused by the body adapting to a new diet consisting of very few carbohydrates.

Symptoms of keto flu include:

• Nausea
• Headaches
• Mental fog
• Constipation
• Diarrhea
• Fatigue
• Irritability
• Poor focus and concentration
• Stomach or intestinal pain
• Sugar cravings
• Cramping
• Muscle soreness
• Dizziness
• Trouble sleeping

To help alleviate keto flu symptoms, it is recommended to:

• Drink plenty of water
• Eat more frequently and include plenty of colorful vegetables
• Get enough sleep
• Avoid strenuous exercise
• Replace electrolytes
• Make sure you are eating enough fat and carbohydrates
• Include cheat days
• Eat adequate carbohydrates

Ketosis

The keto diet is based on research from the 1920s that found lowering the availability of carbohydrates made the body rely more on using other substances (such as fat) for energy. By metabolising fat to produce glucose or energy, the body generates ketones in the process. Any diet containing less than 20g per day of carbohydrates is deemed to be ketogenic.

The production of ketones by the liver indicates that fat, instead of sugar, is being metabolised and that this fat is close to our entire source of energy. This is thought to correlate with weight loss but really correlates with an altered blood insulin profile.

Many people report experiencing something called the "keto flu" after changing their diet. Symptoms include nausea, constipation, headaches, fatigue and sugar cravings, similar to influenza. These side effects are related to the key concept of the ketogenic diet: carbohydrate withdrawal.

Glucose is the primary energy source of the central nervous system, including the brain. A reduced supply of carbohydrates will result in reduced function, leading to headaches. Nausea can be explained by consuming high volumes of fat. This is because fat takes a long time to digest and absorb.

The keto flu commonly occurs during the first week of the keto diet. On average, it may last up to one to two weeks. For some people, it may last for a month.

• Change your meal: Adjust your time and portion according to your diet.
• Start gradually: Let your body adjust to your diet. Reduce your food intake at a slower pace.
• Include cheat days: Eat whatever you like. Just be careful, don’t overwhelm your body.
• Eat adequate carbs: No diet encourages you to eat zero sugar. Moreover, a minimal amount of glucose is vital for your brain. If you suddenly eat no sugar, you may feel sick.
• Keep yourself hydrated: Drink plenty of water throughout the day. It may alleviate the keto flu symptoms.

Carbohydrate withdrawal

The symptoms of the keto flu can include:

• Nausea
• Headaches
• Fatigue
• Lack of motivation
• Confusion
• Brain fog
• Irritability
• Stomach or intestinal pain
• Diarrhea
• Muscle soreness
• Cravings

These symptoms are usually mild and temporary, lasting from a few days to several weeks. They are caused by a combination of dehydration, salt deficiency, and withdrawal from carbohydrates, which the body is used to using as its main source of energy.

To alleviate the symptoms of the keto flu, it is recommended to:

• Drink plenty of water
• Consume bone broth or bouillon for added electrolytes
• Increase your intake of salt
• Get enough sleep
• Avoid strenuous exercise
• Eat more fat and protein
• Cut out carbs slowly

Cortisol secretion

Cortisol is a steroid hormone produced and released by the adrenal glands, which are endocrine glands located on top of the kidneys. It is often referred to as the "stress hormone" as it plays a crucial role in regulating the body's response to stress. However, cortisol has a wide range of effects on the body beyond stress management.

The secretion of cortisol is regulated by the hypothalamus-pituitary-adrenal (HPA) axis. This is a complex interplay between the hypothalamus, the pituitary gland, and the adrenal glands. When cortisol levels in the blood drop, the hypothalamus releases corticotropin-releasing hormone (CRH), which signals the pituitary gland to produce adrenocorticotropic hormone (ACTH). ACTH then stimulates the adrenal glands to secrete cortisol. This process is known as a negative feedback loop, where high levels of cortisol inhibit the release of ACTH and CRH, maintaining a balance in the body.

Factors Influencing Cortisol Secretion

Several factors can influence cortisol secretion:

• Stress: During stressful situations, the body releases cortisol as part of the "fight or flight" response, keeping the body on high alert.
• Circadian Rhythm: Cortisol levels follow a daily rhythm, with higher levels in the morning and lower levels at night. This is why cortisol is linked to the regulation of the sleep-wake cycle.
• Exercise: Strenuous physical activity can stimulate the adrenal cortex to release cortisol. The intensity and duration of exercise influence this response, with more prolonged and intense exercise leading to higher cortisol levels.
• Diet: Dietary choices can impact cortisol levels. For example, the ketogenic diet, which involves a significant reduction in carbohydrate intake, may affect cortisol secretion indirectly by influencing energy levels and metabolism.

Cortisol and Exercise

Research has shown that exhaustive exercise can lead to increased cortisol levels during and after physical activity. In a study involving male endurance athletes, 73.5% of the participants exhibited peak cortisol responses during the recovery period after volitional exhaustion. This suggests that cortisol levels can remain elevated even after the cessation of exercise.

Cortisol and the Ketogenic Diet

While there is limited direct evidence linking the ketogenic diet to cortisol secretion, it is important to consider the potential indirect effects. The ketogenic diet's very low-carbohydrate nature can lead to decreased energy levels, especially during high-intensity exercises. This reduction in energy availability may influence cortisol secretion as the body responds to the stress of exercise. Additionally, the ketogenic diet's impact on metabolism and potential flu-like symptoms may also play a role in cortisol regulation.

In summary, while the link between the ketogenic diet and cortisol secretion is not well-established, the diet's influence on energy levels, metabolism, and overall stress response may indirectly affect cortisol secretion. Further research is needed to fully understand this relationship.

Insulin response

The ketogenic diet (KD) is a low-carbohydrate, high-fat diet that has been linked to a range of potential health benefits, including improved blood sugar control and decreased hunger levels. However, its effect on athletic performance remains controversial. While some claim that keto can boost fat burning and enhance endurance, others argue that it could drain energy levels and impair muscle growth.

The impact of a KD on insulin sensitivity is complex and not yet fully understood. Insulin is a hormone that helps regulate blood sugar levels, and insulin resistance is a condition where the body's cells become less responsive to insulin, leading to increased blood sugar levels. This condition is a precursor to type 2 diabetes.

Research suggests that a KD can have both direct and indirect effects on insulin sensitivity. The indirect effects are mediated by the diet's impact on fat tissue, particularly visceral fat, which is known to affect insulin sensitivity more than subcutaneous fat. A KD can significantly reduce visceral fat depots, leading to improved insulin sensitivity. Additionally, a KD may act on skeletal muscle with an "exercise-type" mechanism, improving mitochondrial capacity and efficiency, which can also enhance insulin sensitivity.

The direct effects of a KD on insulin sensitivity are mainly due to the diet's ability to lower blood glucose and insulin levels. By restricting carbohydrate intake, a KD decreases intestinal absorption of monosaccharides, leading to reduced postprandial glycemia and lower insulin requirements. This, in turn, can improve insulin sensitivity.

Furthermore, ketone bodies produced during a KD may have a direct effect on insulin signaling. Ketone bodies, such as beta-hydroxybutyrate (BHB), can influence insulin signaling directly or indirectly through their impact on other molecules and pathways. BHB has been shown to activate the G-protein-coupled receptor HCA2/GPR109a, which has a role in the inflammation pathway and lipolysis. Activation of this receptor can lead to reduced plasma levels of free fatty acids and glucose, improving insulin sensitivity.

In summary, a KD can improve insulin sensitivity through its effects on fat and weight loss, as well as through direct effects on insulin signaling and pathways related to oxidative stress, inflammation, and mitochondrial efficiency. However, more research is needed to fully understand the mechanisms underlying the impact of a KD on insulin sensitivity.

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