Keto And High Blood Sugar: What's The Deal?

The keto diet is a low-carb, high-fat dietary regimen that has been linked to improvements in insulin sensitivity and higher rates of weight loss — both positive factors in managing type 2 diabetes. Lowering carb intake induces a metabolic state known as ketosis, through which the body produces ketones that burn fat — rather than carbohydrates — for energy. However, despite the benefits of the keto diet, some people may experience higher fasting blood glucose levels while on the diet. This phenomenon is called physiologic insulin resistance or adaptive glucose sparing, and it occurs because the body has adapted to using fat, rather than sugar, as fuel. This means that the muscles start to reject sugar, leading to more sugar staying in the bloodstream even when consumption is low. While this can be concerning, experts recommend monitoring other health metrics such as glycemic variability, fasting insulin, HDL, triglycerides, and liver enzymes to ensure overall health. Additionally, it is important to note that blood glucose levels are just one indicator of health, and other factors such as exercise, sleep, and stress can also impact blood sugar levels.

Physiologic insulin resistance or adaptive glucose sparing is a normal response to a keto diet

Physiologic insulin resistance, or adaptive glucose sparing, is a normal response to a keto diet. This phenomenon occurs when the body, instead of using glucose for energy, starts using fat as its primary source of fuel. As a result, the muscles start to resist the action of insulin, which normally brings sugar into cells for energy. This leads to slightly elevated but generally stable glucose levels in the blood.

This condition is different from pathologic insulin resistance, which is caused by increasingly higher levels of insulin trying to force glucose into cells. Physiologic insulin resistance, on the other hand, is likely a good thing and is not something to be concerned about. It is a natural protective process that allowed humans to survive through periods of feast and famine.

When on a keto diet, it is common for fasting blood glucose levels to be higher, and this can be explained by physiologic insulin resistance. However, it is important to monitor both fasting blood glucose and fasting insulin levels to fully understand how the body is responding to the diet. Additionally, factors such as stress and sleep can also impact blood glucose levels.

In summary, physiologic insulin resistance, or adaptive glucose sparing, is a normal and healthy response to a keto diet, and it should not be a cause for alarm.

It's important to monitor other health metrics such as glycemic variability, fasting insulin, HDL, triglycerides, and liver enzymes

While on a keto diet, it is important to monitor other health metrics such as glycemic variability, fasting insulin, HDL, triglycerides, and liver enzymes. This is because these metrics can provide valuable information about your overall health and help ensure that your keto diet is not having any negative effects on your body.

Glycemic variability refers to swings in blood glucose levels throughout the day, including periods of hypoglycemia and postprandial increases. Monitoring glycemic variability can help identify patterns and trends in your blood glucose levels, which can be important for managing diabetes or improving metabolic control. It is also a good way to assess the effectiveness of your keto diet in controlling blood glucose levels.

Fasting insulin levels are important to measure because they can indicate how sensitive or resistant your body is to insulin. High fasting insulin levels may be a sign of insulin resistance, which is a risk factor for type 2 diabetes and other health issues. Monitoring fasting insulin can also help evaluate the effectiveness of your keto diet in improving insulin sensitivity.

HDL, or high-density lipoprotein, is the "good" cholesterol that helps remove excess cholesterol from your bloodstream. Monitoring HDL levels while on a keto diet is important because keto diets are typically high in fat and can affect cholesterol levels. Maintaining adequate HDL levels can help reduce the risk of cardiovascular disease.

Triglycerides are a type of fat found in the blood that can increase the risk of heart disease and other health issues if they are too high. Keto diets that are high in fat and calories can lead to increased triglyceride levels. Therefore, monitoring triglyceride levels is crucial to ensure that your keto diet is not negatively impacting your heart health.

Liver enzymes are proteins produced by the liver that can indicate liver function and damage. Elevated liver enzymes may be a sign of liver disease or injury. Monitoring liver enzymes while on a keto diet is important because the diet can put extra strain on the liver, especially if it is high in fat and calories.

Overall, monitoring these health metrics can provide valuable insights into the effectiveness and safety of your keto diet. It is important to work with a healthcare professional to interpret the results and make any necessary adjustments to your diet or lifestyle.

Keto diets can lead to temporary physiological insulin resistance, where the body overreacts when carbs are introduced

Keto Diets and Temporary Physiological Insulin Resistance

How Keto Diets Affect the Body

The ketogenic diet, commonly known as "keto", is a low-carbohydrate, high-fat diet. 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. However, keto diets can also have some potential downsides, including temporary physiological insulin resistance.

How Keto Diets Affect Insulin and Glucose

When following a keto diet, the body switches from using exogenous glucose (from carbohydrates) for energy to using glycogen (stored glucose) and producing its own glucose through gluconeogenesis. As a result, keto diets can lead to lower insulin levels and stable glucose levels.

However, one common trend observed in individuals on a keto diet is slightly higher glucose responses to small amounts of carbs. This is because keto diets can lead to a temporary physiological insulin resistance, where the body overreacts when carbs are introduced. The muscles, which typically prefer glucose, start to prefer fatty acids for fuel instead. Muscles are a major site for glucose uptake, so when they start to prefer fatty acids, consuming carbs can cause larger glucose elevations.

Managing Temporary Physiological Insulin Resistance

It is important to understand your carb threshold and what type of carbs you tolerate best to maintain metabolic flexibility. This will allow your body to quickly shift between using ketones and glucose, without becoming dependent on just glucose. You can also test your trigger foods and experiment with portion sizes to find what works best for your body.

In addition, there are several strategies that may help prevent spikes in blood sugar when reintroducing carbs:

• Eat fiber (vegetables) and proteins/fats first, and carbs last.
• Drink a glass of water with apple cider vinegar before or during your meal.
• Avoid eating carbs later in the evening, when your body is less sensitive to insulin.
• Incorporate post-meal walks into your daily routine.
• Exercise regularly to improve insulin sensitivity and cardiometabolic health.
• Get adequate sleep to live in alignment with your body clock.

The relationship between ketones and glucose is inverse, so monitoring both is beneficial

The keto diet has gained popularity in recent years, with many people adopting it for weight loss and blood sugar management. While the keto diet can be effective in lowering blood glucose levels, some people may experience higher fasting blood glucose levels while on the diet. This can be surprising and concerning for individuals, especially those with diabetes or prediabetes. However, it's important to understand the relationship between ketones and glucose to make sense of this phenomenon.

When an individual follows a ketogenic diet, they drastically reduce their carbohydrate intake, which lowers the body's exogenous glucose sources. As a result, the body turns to glycogen (stored glucose) and gluconeogenesis (glucose production from non-carbohydrate sources) to meet its glucose needs. Additionally, the body starts using ketones as an alternative fuel source. Ketones are produced from fatty acids when glucose availability drops, and they replace glucose as the primary energy source. This is known as ketosis.

The relationship between ketones and glucose is inverse. When ketone levels increase, glucose levels tend to decrease, and vice versa. This is because the body is now using ketones as its primary energy source instead of glucose. However, this doesn't mean that glucose levels will always be low during ketosis.

During prolonged ketosis, the body may exhibit a phenomenon called "glucose sparing" or "physiologic insulin resistance." This means that even though ketone levels are high, indicating the body is using ketones for energy, there can still be glucose circulating in the blood. This is particularly common in individuals who have been following a strict keto diet for an extended period. The body ensures that glucose is available for organs that require it, such as the brain. While this is a natural adaptation, it's important to monitor other health metrics to ensure overall health.

Monitoring both ketone and glucose levels is beneficial for individuals on a keto diet. By using a continuous glucose monitor and tracking ketone levels, individuals can gain a clearer picture of their body's energy usage. This can help them understand their glucose trends, identify trigger foods, and make informed decisions about their diet and lifestyle. Additionally, monitoring ketone and glucose levels can provide valuable insights for individuals with diabetes or prediabetes, helping them manage their blood sugar levels effectively.

In conclusion, the inverse relationship between ketones and glucose means that monitoring both is crucial for individuals on a keto diet. By tracking ketone and glucose levels, people can better understand their body's energy dynamics, make necessary adjustments to their diet and lifestyle, and ensure overall health and well-being.

The CGM (Continuous Glucose Monitor) can help identify trigger foods and optimise your keto diet

The keto diet is a high-fat, low-carb diet that aims to put your body into a state of ketosis, where it burns fat for energy instead of glucose. While on the keto diet, it's important to monitor your blood glucose levels to ensure you're staying within a healthy range. This is where a CGM (Continuous Glucose Monitor) device comes in.

A CGM device is a small, wearable sensor that measures your glucose levels continuously throughout the day, providing real-time data via a smartphone app. This data can be incredibly useful for optimising your keto diet and identifying any trigger foods that may be causing spikes in your blood sugar.

• Identifying trigger foods: By wearing a CGM, you can easily identify which foods cause spikes in your blood sugar. This information can be used to optimise your keto diet and ensure you're only consuming foods that align with your health goals. For example, you may discover that a particular ""keto-friendly" food is actually causing your glucose levels to spike.
• Personalised diet plans: With a CGM, you can develop a finely-tuned, data-driven, personalised diet plan. You are no longer restricted to a one-size-fits-all approach but can instead make informed decisions about your dietary choices based on real-time data.
• Avoiding keto setbacks: A CGM can help you avoid dietary setbacks that could kick you out of ketosis. For example, you may discover that a certain food you assumed was keto-friendly is actually causing your glucose levels to rise.
• Understanding fasting glucose levels: If you've been on the keto diet for an extended period, you may experience high fasting glucose levels, also known as "adaptive glucose sparing" or "physiologic insulin resistance". This is a normal and likely beneficial response, but it can be confusing if you don't understand the underlying mechanisms. A CGM can help you track these levels and work with your healthcare provider to interpret the data.
• Experimenting with portion sizes: A CGM can provide insights into your body's carb tolerance, helping you understand how many carbs you can consume while staying in ketosis. This information can guide your portion sizes and meal planning.
• Identifying your carb threshold: By gradually increasing your carbohydrate intake while monitoring your glucose levels with a CGM, you can identify your personal carb threshold—the amount of carbs you can consume while maintaining ketosis.

In conclusion, a CGM can be a valuable tool for anyone following the keto diet. It provides data-driven insights that can help you optimise your diet, identify trigger foods, and make informed decisions about your nutritional choices. By using a CGM, you can take the guesswork out of keto and ensure you're on a sustainable path to achieving your health goals.

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