Keto And Blood Sugar: What's The Connection?

The ketogenic diet is a popular lifestyle choice for weight loss, weight management, and overall health. However, some people on the keto diet are surprised to find that they have high levels of glucose in their blood. This is because the keto diet can impair your muscles' ability to take up glucose in response to insulin, leading to a disorder called insulin resistance. While the keto diet can lead to short-term weight loss, it is generally unsustainable and unhealthy in the long term. Eating too much fat or protein on the keto diet can also increase insulin resistance and lead to high blood glucose levels.

Eating too much fat can increase insulin resistance and lead to high blood sugar

Insulin resistance is a condition in which the body does not respond adequately to insulin, a hormone produced by the pancreas that is essential for regulating blood sugar levels. Insulin resistance can be temporary or chronic and is treatable in some cases.

When you eat too much fat, it can build up inside your muscle cells, creating toxic fatty breakdown products and free radicals that interfere with the insulin signalling process. This is known as intramyocellular lipids, or fat inside muscle cells. As a result, insulin is unable to effectively unlock the door for glucose to enter the muscle cells, causing blood sugar levels to rise.

Studies have shown that a high-fat diet can lead to increased blood sugar spikes and glucose intolerance compared to a high-carb diet. Within just two days, participants on a high-fat diet exhibited twice the blood sugar levels of those on a high-carb diet. This demonstrates that the sugar tolerance of even healthy individuals can be impaired by a low-carb, high-fat diet.

On a ketogenic diet, the body becomes insulin resistant as it prioritises fat as fuel instead of glucose. This is known as "physiologic insulin resistance" or "glucose sparing", and it is considered a natural and beneficial adaptation. However, it's important to monitor other health metrics to ensure that everything remains within a healthy range.

To reduce insulin resistance, it is recommended to lower fat intake, engage in regular physical activity, and lose excess weight. These lifestyle modifications can increase insulin sensitivity, lower blood glucose levels, and improve overall health.

Eating too much protein can prevent ketosis and cause high blood sugar

The keto diet is a low-carb, high-fat diet that aims to put the body into a state of ketosis, where it burns fat for energy instead of glucose. While controlling carb intake is crucial on the keto diet, monitoring protein intake is also essential. This is because eating too much protein can prevent the body from entering ketosis.

When there is a lack of exogenous glucose (glucose from external sources) due to low carb intake, the body switches to using glycogen (stored glucose) and producing its own glucose through a process called gluconeogenesis. This process ensures that organs that require glucose, such as the kidneys and brain, receive enough to function properly.

Gluconeogenesis creates glucose from non-carbohydrate sources, including protein. This has led to the concern that consuming too much protein on the keto diet could lead to increased glucose levels and prevent ketosis.

However, the idea that too much protein can kick you out of ketosis is a myth. Eating protein does not affect ketone levels, and you can stay in ketosis while consuming high-protein foods. In fact, gluconeogenesis is necessary for survival and makes ketosis possible in the first place.

During ketosis, the body uses gluconeogenesis for three main purposes:

• Preventing hypoglycemia: Gluconeogenesis keeps blood sugar levels within a healthy range, preventing them from dropping too low.
• Fuelling tissues that cannot use ketones: Some cells in the body, such as red blood cells and certain parts of the brain, can only use glucose for energy. Gluconeogenesis provides them with the glucose they need.
• Resupplying glycogen stores: Gluconeogenesis helps replenish muscle glycogen, which is crucial for muscle recovery after workouts.

While gluconeogenesis is essential, it is important to consume an adequate amount of protein on the keto diet. This is because protein:

• Helps with fat loss: Protein is more satiating than fat, making it easier to stick to a calorie deficit.
• Provides fewer calories than fat: The body uses more energy to burn protein compared to fat.
• Deficiency is dangerous: Not getting enough protein can lead to worsened workout performance, neuron atrophy, a weaker immune system, and an increased risk of certain diseases.

To ensure you are consuming an optimal amount of protein on the keto diet, it is recommended to:

• Calculate your protein intake: Use a keto calculator or macro calculator to determine your ideal protein intake based on factors such as activity level and body composition.
• Test your ketone levels: If you are concerned about consuming too much protein, you can use a blood ketone meter to monitor your ketone levels and adjust your protein intake accordingly.
• Focus on long-term lean tissue growth: Instead of solely focusing on ketone levels, track your overall body composition and energy levels to gauge the effectiveness of your keto diet.

The keto diet can cause insulin resistance and high blood sugar

The keto diet has become a popular lifestyle choice for many, with advocates claiming it aids weight loss, weight management, and overall health. The diet involves deriving seventy to seventy-five percent of daily calories from fat, fifteen to twenty percent from protein, and five percent from carbohydrates. While some people have reported success with the keto diet, others have been surprised to find high levels of glucose (or sugar) in their blood while following this diet.

Insulin resistance

The keto diet can impair your muscles' ability to take up glucose in response to insulin, leading to a condition called insulin resistance. Insulin is a hormone that regulates blood sugar. Normally, it acts as a key, unlocking muscle cell membranes and allowing glucose to enter and be used as fuel. However, when muscle cells become insulin resistant, glucose accumulates in the blood instead of entering the cells. This can result in high blood glucose levels, also known as diabetes, as well as low energy and fatigue.

According to Dr Nikola Djordjevic, MD from MedAlertHelp.org, the keto diet's effectiveness in lowering blood glucose levels is only partially correct. Substituting fat for sugar may not be sustainable over time, and high dietary fat intake can increase insulin resistance. This, in turn, can lead to high glucose levels in the blood and increase the risk of developing chronic conditions such as high cholesterol.

Temporary physiological insulin resistance

The keto diet can lead to a temporary form of physiological insulin resistance. This is different from pathological insulin resistance, which is a disease state. Physiological insulin resistance occurs when the muscles, which typically prefer glucose, start to prefer fatty acids for fuel instead. Muscles are a major site for glucose utilisation, so when they start to prefer fatty acids, consuming carbohydrates can cause larger glucose elevations in the blood.

Building up insulin resistance over time

The keto diet can also indirectly lead to insulin resistance over time by making it difficult for people to exercise. According to Dr Carla Hightower, the founder of Living Health Works, the keto diet tends to burn not only fat but also muscle. This can weaken the muscles and make it harder for people to exercise. As a result, individuals on a keto diet are more likely to gain weight, which, by itself, causes insulin resistance.

If you are experiencing high blood glucose levels while on the keto diet, there are a few things you can do:

• Monitor other health metrics such as glycemic variability, fasting insulin, HDL, triglycerides, and liver enzymes to ensure they remain in a healthy range.
• Understand your carb threshold and the types of carbs you tolerate best to maintain metabolic flexibility.
• Identify your trigger foods and reduce or eliminate them from your diet.
• Test your protein threshold to ensure you are not consuming excess protein, which can be converted into glucose.

High blood sugar can be caused by cortisol, the stress hormone

Cortisol, also known as the "stress hormone", is a steroid hormone produced and released by the adrenal glands, which are endocrine glands located on top of the kidneys. It plays a crucial role in regulating the body's response to stress and has a direct impact on blood glucose levels.

During stressful situations, the body releases cortisol as part of the "fight-or-flight" response, triggering the release of glucose from the liver for a quick energy boost. This process, known as gluconeogenesis, ensures that the body has the necessary fuel to respond to perceived threats. However, if the stress is not resolved and the energy from the glucose release remains unused, it can lead to prolonged higher glucose levels in the blood.

Chronically elevated cortisol levels can have detrimental effects on the body. It can lead to a constant state of insulin resistance, as cortisol counterbalances the effects of insulin. Over time, this can result in persistently high blood sugar levels, also known as hyperglycemia, which is a characteristic of Type 2 diabetes. Additionally, elevated cortisol levels can contribute to weight gain, particularly visceral fat storage, by mobilizing triglycerides and promoting the development of adipocytes (fat cells).

Furthermore, high cortisol levels can suppress the immune system by reducing inflammation. While short-term inflammation reduction is beneficial, consistently high cortisol levels can weaken the immune system, making individuals more susceptible to illnesses and infections.

To manage cortisol levels, it is essential to address stress. This can be achieved through various strategies such as improving sleep quality, regular exercise, deep breathing exercises, and engaging in enjoyable activities that promote laughter and a sense of well-being. Additionally, maintaining healthy relationships and learning to limit stressful thinking patterns can help reduce stress levels and, consequently, cortisol levels.

In summary, cortisol, the stress hormone, plays a significant role in regulating blood sugar levels. While short-term stress responses are normal, chronic stress and elevated cortisol levels over an extended period can have negative consequences for overall health, including contributing to high blood sugar and an increased risk of Type 2 diabetes. Therefore, managing stress and maintaining optimal cortisol levels are crucial for maintaining overall health and well-being.

Glucose meters can give false readings

While higher glucose readings can be caused by physiological reasons, technical reasons can also cause them. The US Federal Drug Administration (FDA) allows home glucose monitors to have a variance of 15% in results. This means that a reading of 100 mg/dl might actually be as low as 85 mg/dl or as high as 115 mg/dl, a significant variation.

Dave Feldman, a software engineer, has blogged about the variance in his glucose meter readings. He was surprised by the sometimes huge variation in results, even when measuring the same drop of blood with two different meters. Whenever he gets an unexpected result, he takes three readings within a few minutes of each other and then averages the result.

Other researchers have noted that false readings can be caused by various factors, including:

• Pricking a finger for blood with hands that have traces of sugar or food on them (e.g. from touching a piece of fruit).
• Dehydration, which can raise glucose readings.
• Soap residue on the fingers, especially soaps with additives like honey or fragrance, which can distort readings.
• Environmental conditions like high altitudes.
• Strips that are too hot or too cold, which can produce higher or lower readings.
• Different lots of strips, which can produce different results on the same meter.

If you get an unusually high reading, it is recommended to take another reading. It is often many points lower.

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