Keto And Carb Aversion: What's The Connection?

The ketogenic diet is a low-carbohydrate method of eating that switches the body's main fuel source from carbohydrates to fat. While it can lead to weight loss, improved insulin sensitivity, and other health benefits, it also has some potential downsides. One such downside is that it can cause a temporary aversion to carbohydrates, also known as carbohydrate intolerance or sensitivity. This occurs because the body becomes more efficient at using fat as fuel and less efficient at using carbohydrates. When reintroducing carbs after being on the keto diet, some people may experience digestive issues, fatigue, and even weight gain due to higher insulin levels. This phenomenon is normal and usually resolves within two weeks as the body readjusts to using carbs for energy.

Carbohydrate intolerance

When carbs are eliminated from the diet, the body enters a metabolic state called ketosis, where it burns stored fat for energy. This can lead to weight loss, improved insulin sensitivity, and other health benefits, but it also has some potential downsides.

Those wearing a continuous glucose monitor might notice they’ve become extremely sensitive to carbs and experience a higher-than-normal glucose spike after transitioning back from keto — even if they only eat a small number of carbs. They may also feel very tired or experience digestive issues when they reintroduce the carbs they once enjoyed, and even regain a bit of weight due to higher insulin levels.

This phenomenon (known as carbohydrate intolerance) is a normal response when the body is adapting to these changes in diet. That’s because your metabolism is like a hybrid car that can use both gas and electric power for energy (i.e., fat and carbs). However, unlike hybrid cars, if you’ve been limiting your body to one source of energy (fat), it’ll take some time to gradually become efficient at using the other one (carbs) again.

Carbohydrate sensitivity or intolerance is a condition where your body has difficulty properly metabolizing carbohydrates — which is also known as temporary insulin resistance. Your body's cells temporarily become less responsive to the hormone insulin. Insulin regulates blood sugar levels by helping to transport glucose from the bloodstream into the cells, where it can be used as a source of energy. When you have temporary insulin resistance, cells do not respond to insulin as well as they should, leading to elevated blood sugar levels.

Sensitivity to carbs can also result in a variety of symptoms, including abdominal pain, bloating, gas, diarrhoea, constipation, and fatigue.

Slowly reintroducing carbs can help the process, starting with foods that have a low glycemic index. Over time, the temporary insulin resistance and carb sensitivity will subside.

If you’ve been on keto for a while (say, one year or longer), you may be wondering how long it will take your body to overcome your carb sensitivity. Right now, there isn't much available literature on long-term keto diets — many studies that follow "long-term keto" participants only last about 6 months. For most people, however, it can take about 2 weeks to readjust to carbs (though this likely won't be as much of an issue if you've only done keto for a few days).

Citrin deficiency

• Neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD): This typically presents in newborns or infants and is characterised by transient cholestasis, fatty liver, growth restriction, and variable liver dysfunction. With appropriate treatment, symptoms often resolve by the age of one, although rare cases may require liver transplantation.
• Failure to thrive and dyslipidemia caused by citrin deficiency (FTTDCD): This occurs in older children and is characterised by growth restriction, hypoglycaemia, pancreatitis, severe fatigue, anorexia, and impaired quality of life. Laboratory findings include dyslipidaemia, increased oxidative stress markers, and deviations in tricarboxylic acid cycle metabolites.
• Adult-onset type II citrullinemia (CTLN2): This typically presents between the ages of 20 and 50 and is characterised by recurrent hyperammonemia and neuropsychiatric symptoms such as delirium, aggression, irritability, and disorientation. Symptoms can be triggered by alcohol and sugar intake, medication, or surgery.

A unique feature of citrin deficiency is a strong preference for protein- and fat-rich foods and an aversion to carbohydrate-rich foods. This is because the disorder disrupts the body's ability to process carbohydrates, leading to hyperammonemia and metabolic disturbances. Treatment of citrin deficiency aims to prevent or manage these complications. For NICCD, treatment includes medium-chain triglyceride (MCT)-enriched formulas and fat-soluble vitamin supplements. For CTLN2, liver transplantation is the most effective treatment, although it is intensive and costly. Dietary management is crucial, particularly a low-carbohydrate and high-protein/fat diet. Sodium pyruvate supplementation and arginine administration can also help manage symptoms.

Keto flu

The "keto flu" is a group of symptoms that may appear two to seven days after starting a ketogenic diet. The symptoms are similar to those of the flu and are caused by the body adapting to a new diet consisting of very few carbohydrates.

The ketogenic diet is very low in carbohydrates, high in fat, and moderate in protein. Reducing your carb intake forces your body to burn ketones for energy instead of glucose. Ketones are byproducts of fat breakdown and become the main fuel source when following a ketogenic diet.

Some of the most frequently reported symptoms of keto flu are:

• Headaches
• Fatigue
• Irritability
• Nausea
• Diarrhea or constipation
• Muscle soreness
• Sugar cravings
• Poor focus and concentration
• Brain fog
• Trouble sleeping

The keto flu can last from a few days to several weeks, and in extreme cases, it can last up to a month. However, depending on your genetics, you may never experience the keto flu at all. Some people are naturally "metabolically flexible," meaning they can shift metabolic states easily without experiencing health symptoms.

• Drink plenty of water. Staying hydrated helps with headaches and boosts your energy levels.
• Take an electrolyte supplement. Adding electrolytes like salts, potassium, and magnesium to your diet can help with cramps and nausea.
• Consume enough healthy fats. Low calories can lead to keto flu symptoms, so don't reduce your calorie intake too much, and avoid going low-carb and low-fat at the same time.
• Get plenty of rest. If you're having trouble sleeping, try taking an Epsom salt bath to relax your muscles and improve electrolyte absorption.
• Try light exercise, such as restorative yoga, to help relieve muscle pain and tension and boost your mood and motivation.

Weight loss

The ketogenic diet is a low-carbohydrate, high-fat diet that switches the body's main fuel source from carbohydrates to fat. When carbs are eliminated from the diet, the body enters a metabolic state called ketosis, where it burns stored fat for energy, leading to weight loss.

During the initial stages of a ketogenic diet, people may experience increased thirst, muscle cramps, headaches, fatigue, and weakness as the body transitions from burning carbohydrates to burning fat for energy. Carbohydrates provide a quicker burst of energy, so it takes time for the body to adjust to using fat as its primary fuel source.

To achieve and maintain weight loss on a ketogenic diet, it is important to monitor your food intake and make sure you are getting enough electrolytes, such as calcium, magnesium, potassium, and sodium. Eating a balanced diet that includes low-carb vegetables, healthy fats, and adequate protein is crucial.

Some people may also experience stomach complaints, constipation, and changes in their sleeping patterns when starting a ketogenic diet. These side effects usually subside as the body adjusts to the new way of eating.

It is important to note that weight loss on a ketogenic diet may not be linear, and there may be periods of weight fluctuation. Additionally, the long-term health outcomes of the ketogenic diet are not yet fully known, as most studies have been conducted for less than a year.

When transitioning back to a non-ketogenic diet, it is important to do so gradually. The body becomes more efficient at using fat as fuel and less efficient at using carbohydrates during ketosis. Therefore, reintroducing carbohydrates too quickly can lead to carbohydrate intolerance or temporary insulin resistance, causing digestive issues, fatigue, and weight gain.

To maintain weight loss and avoid these issues, it is recommended to slowly reintroduce carbohydrates and increase the amount gradually over time. This allows the body to adjust and become efficient at using carbohydrates for fuel again. Additionally, focusing on fiber intake during this transition can aid in weight maintenance, as fiber is associated with more successful weight loss.

Electrolyte imbalance

The keto diet is a low-carbohydrate, high-fat diet that switches the body's main fuel source from carbohydrates to fat. While the keto diet has gained popularity due to its benefits, such as weight loss and improved insulin sensitivity, it can also cause an electrolyte imbalance in the body.

Electrolytes are minerals in the body that aid in cellular and organ function and are essential for survival. They are responsible for maintaining hydration and acidity levels, as well as helping to maintain muscle and nerve function. The most common electrolytes found in the body include sodium, chloride, potassium, magnesium, calcium, phosphorus, and bicarbonate.

When following a keto diet, the body begins to process electrolytes differently. The reduction in carbohydrate intake leads to lower insulin levels, which causes the kidneys to excrete more sodium. As the body loses sodium, the balance of other key electrolytes can also be affected. This electrolyte imbalance is often linked to symptoms of "keto flu," which include low energy, muscle cramps, brain fog, headaches, weakness, and insomnia. It can also cause irritability and difficulty concentrating.

To address this electrolyte imbalance, it is important to increase the intake of electrolytes through diet or supplementation. Sodium, potassium, and magnesium are the electrolytes that are most commonly affected by the keto diet.

Sodium is an important electrolyte for maintaining blood volume and blood pressure, controlling nerve impulses, and regulating water retention. On a keto diet, it is recommended to increase sodium intake by using more table salt or sodium chloride in everyday foods. Himalayan sea salt is a mineral-rich option. During training or other physical activities, salty snacks or performance drinks with a high sodium content can help replace lost electrolytes.

Potassium is another key electrolyte that helps prevent muscle cramps, maintain healthy blood pressure, and support heart health. Avocados, portabella mushrooms, almonds, spinach, Brussels sprouts, salmon, and Swiss chard are keto-friendly food sources of potassium. Potassium supplements are also available if needed.

Magnesium is the fourth most abundant mineral in the body and plays a crucial role in DNA and RNA synthesis, muscular contraction, and controlling blood pressure. It also supports the immune system and heart rhythm. Magnesium supplements or adding leafy green vegetables, chia seeds, hemp seeds, macadamia nuts, or almonds to the diet can help increase magnesium levels.

While electrolyte supplements are an option, it is best to prioritise getting electrolytes from food sources whenever possible. It is also important to note that excessive electrolyte intake can have serious health complications, so it is recommended to consult with a healthcare professional before starting any new diet or supplementation regimen.

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