Low-Carb Diet: Dizziness And Other Unexpected Side Effects

A low-carb diet can cause dizziness, especially when you're starting out. This is because low-carb diets like keto aim to put your body in a state of nutritional ketosis, where fat is burned for fuel instead of carbohydrates. As your body transitions into ketosis, it burns through your glycogen stores, which are the backup supply of carbs stored in your muscles and liver. These carbs are stored with large amounts of water and electrolytes such as potassium and sodium, which help regulate your body's fluid balance. As you burn through your glycogen stores, all of the water and electrolytes are flushed out, which can lead to dehydration and a drop in blood pressure, causing dizziness. Additionally, a sudden drop in blood sugar levels due to reduced carbohydrate intake can also lead to dizziness.

Dehydration

Another reason for dehydration on a low-carb diet is the decrease in glycogen stores. Glycogen is a backup supply of carbohydrates stored in the muscles and liver, and it is stored with large amounts of water and electrolytes such as potassium and sodium. As your body burns through these glycogen stores, all the water and electrolytes are flushed out through urine, which can result in dehydration.

In addition to dehydration, a low-carb diet can also cause a drop in blood sugar levels, which may contribute to feelings of dizziness. It is important to monitor your blood sugar levels, especially if you have diabetes, and consult your doctor before starting a low-carb diet.

Low blood sugar

Low-carb diets, such as the keto diet, can cause dizziness due to low blood sugar levels. When you start a low-carb diet, the level of sugar in your blood will reduce, and your body could respond to this with low blood sugar.

According to the American Diabetes Association, one of the signs of a low blood sugar level is dizziness, along with shakiness, nervousness, sweating, confusion, increased heart rate, and hunger. Low blood sugar levels can be dangerous, especially in people with diabetes. If you have type 1 or type 2 diabetes, you should speak to your doctor before starting a low-carb or keto diet, especially if you're taking any blood sugar-lowering medications, such as metformin or insulin.

To avoid low blood sugar levels, it is important to monitor your carbohydrate intake and ensure you are consuming enough nutrients. It may also be helpful to ease into the diet slowly, rather than suddenly decreasing your carb intake.

Additionally, staying adequately hydrated can help minimize the risk of low blood sugar levels. According to the Cleveland Clinic, you should drink water regularly and avoid beverages that tend to be dehydrating, such as those with caffeine, sugar, and/or alcohol. Aim to drink enough water so that your urine is clear or pale yellow in color.

If you experience low blood sugar levels, it is important to treat them promptly. Eating a quick source of carbohydrates, such as fruit juice, bread, or a piece of candy, can help restore your blood sugar levels. However, relying on sweet treats to maintain blood sugar levels is not a healthy long-term option. Instead, try pairing a fiber-rich complex carb with a lean protein, such as whole-grain crackers with cheese or cut veggies with hummus.

It is also important to note that consistently undereating or skipping meals to the point of dizziness may be a sign of disordered eating or an eating disorder. If you feel that you would benefit from improving your relationship with food, consider reaching out to a therapist or registered dietitian who specializes in this area.

Electrolyte imbalance

When you start a low-carb diet, your body enters a state of nutritional ketosis, where it burns fat for fuel instead of carbohydrates. This metabolic change can lead to a drop in your blood sugar levels, which may result in dizziness. However, there are also other factors at play, such as fluid and electrolyte imbalances, which can further contribute to feelings of dizziness.

Fluid and Electrolyte Imbalances

As your body transitions into ketosis, it starts burning through your glycogen stores, which are the backup supply of carbohydrates stored in your muscles and liver. These carbs are stored with large amounts of water, which contain electrolytes such as potassium and sodium. As you burn through these glycogen stores, all the water and electrolytes they contain are flushed out through your urine. This can lead to dehydration, which is characterised by extreme thirst, dry mouth, dry skin, fatigue, and dizziness.

Additionally, losing electrolytes can cause dizziness by lowering your blood pressure. Electrolytes such as sodium, potassium, and magnesium play a crucial role in maintaining your body's fluid balance and regulating blood pressure. When there are significant shifts in electrolyte levels, such as when you first start a low-carb or keto diet, you may experience symptoms like dizziness, along with other symptoms of the "keto flu", including headaches, brain fog, fatigue, nausea, and constipation.

Preventing Electrolyte Imbalance

To minimise the risk of electrolyte imbalance and its associated symptoms when starting a low-carb or keto diet, it is important to focus on staying adequately hydrated. This means drinking water regularly and avoiding dehydrating beverages like caffeine, sugar, and alcohol. The Cleveland Clinic recommends drinking enough water so that your urine is clear or pale yellow in colour. The National Academy of Sciences suggests that men need about 13 cups of fluids per day, while women need approximately 9 cups.

In addition to staying hydrated, ensuring adequate electrolyte intake is crucial. You can do this by adding more salt to your diet or consuming a cup of broth daily. However, it is important not to overdo it, as excessive sodium intake can lead to health issues. Aim to stay within the Food and Drug Administration's recommended daily intake of 2,300 mg of sodium.

Nutritional ketosis

The keto diet typically consists of 70% to 80% fats, 10% to 20% proteins, and 5% to 10% carbohydrates. To enter and maintain ketosis, daily carbohydrate intake should be restricted to under 50 grams, which is significantly less than the amount of carbs in the standard Western diet. This level of carbohydrate restriction leaves only vegetables and small amounts of berries as carb options.

• Weight loss: Ketosis can help people feel less hungry, leading to reduced calorie intake and weight loss.
• Increased energy: The body and brain use ketones as their main source of energy, which can result in increased focus and energy levels.
• Treating chronic illnesses: The keto diet has been used to manage and treat various health conditions, including epilepsy, Alzheimer's disease, type 2 diabetes, and heart disease.
• Improved metabolic and inflammatory markers: Nutritional ketosis can lead to improved insulin sensitivity, lower blood sugar levels, and reduced inflammation.
• Appetite suppression: Ketone bodies have been shown to have an appetite-suppressing effect, which can aid in weight loss.

However, it's important to note that the keto diet can also have some side effects, such as "keto flu," which includes symptoms like upset stomach, headache, and fatigue. Other potential risks of a long-term high-fat, high-protein diet include vitamin or mineral deficiencies, high cholesterol, and increased risk of heart disease.

Overall, nutritional ketosis has the potential to provide health benefits, but it should be approached with caution and under the guidance of a medical professional.

Keto flu

The keto flu is a collection of symptoms experienced by some people when they first start a ketogenic diet. The ketogenic diet is very low in carbohydrates, high in fat, and moderate in protein. The diet is considered safe for most people, but it is associated with some unpleasant side effects.

Symptoms

Symptoms of the keto flu can include:

• Headache
• Foggy brain
• Fatigue
• Irritability
• Nausea
• Dizziness
• Sugar cravings
• Cramping
• Muscle soreness
• Diarrhea or constipation
• Trouble falling asleep or staying asleep
• Poor focus and concentration
• Stomach or intestinal pain

These symptoms can range from mild to severe and vary from person to person. They usually begin within the first day or two of starting the diet and can last a week or less. In extreme cases, the keto flu can last up to a month.

Causes

The exact cause of the keto flu is not known, but it is believed to be related to the body's response to entering ketosis, a metabolic process where the body burns fatty acids for energy instead of carbohydrates (glucose). This can be a shock to the body and may result in withdrawal-like symptoms.

Other possible causes include dehydration, electrolyte imbalance, a change in the gut microbiome, and carbohydrate withdrawal.

Management

• Drink plenty of water to stay hydrated and prevent dehydration, which is a common issue on the keto diet.
• Take an electrolyte supplement or increase your intake of electrolytes like salts, potassium, and magnesium.
• Ensure you are eating enough healthy fats, as low calories can lead to keto flu symptoms.
• Get plenty of rest and try to improve your sleep quality.
• Try light exercise, such as restorative yoga, to help relieve muscle pain and tension.
• Ease into the keto diet gradually, instead of quitting carbs "cold turkey."

Frequently asked questions