Understanding Keto: Blood Sugar Dips And Their Causes

The ketogenic diet has become increasingly popular in recent years, with many people adopting it to lose weight. The diet involves consuming a high proportion of fats and a low proportion of carbohydrates, which can change the way the body stores and uses energy. While the keto diet can be beneficial for people with diabetes, it can also cause dips in blood sugar levels. This is because the body is deprived of exogenous glucose, forcing it to switch to glycogen or glucose storage, which causes specific metabolic changes. Additionally, the keto diet can lead to a temporary form of physiological insulin resistance, where the muscles start to prefer fatty acids for fuel instead of glucose. This can result in higher fasting blood glucose levels, which is a common trend among individuals who have been following a keto diet for a prolonged period.

The body converts fat, not sugar, into energy on a keto diet

The keto diet is a high-fat, low-carb diet that can help manage blood sugar levels and reduce the need for insulin. On a keto diet, the body converts fat, not sugar, into energy.

When the body doesn't have enough glucose available to use for energy, it enters a state called ketogenesis. In this state, ketone bodies are created from fatty acids and replace glucose as the body's primary source of energy. The keto diet can be an effective way to manage blood sugar levels, especially for people with type 2 diabetes.

When following a keto diet, the body switches from using glucose as its primary energy source to using fat. This is because the keto diet limits carbohydrate intake, which is the body's main source of glucose. As a result, the body adapts and starts using fat for energy instead. This process is known as ketogenesis.

During ketogenesis, the body breaks down fat into ketone bodies, which can be used as an alternative source of energy. The liver plays a crucial role in this process by producing ketone bodies through a process called ketogenesis. This ensures that the body has enough energy to function properly.

The keto diet has been shown to have benefits for people with type 2 diabetes. It can help improve blood glucose levels and reduce the need for insulin. Additionally, the keto diet can lead to weight loss, which is often a goal for people with type 2 diabetes. However, it's important to note that the keto diet does come with risks and should be discussed with a doctor before making any drastic dietary changes.

While the keto diet can be effective for managing blood sugar levels, it may not be suitable for everyone. Some people may find it challenging to follow due to its restrictive nature. Additionally, there is a lack of long-term research on the benefits of a keto diet for blood sugar management. It's important to work with a healthcare provider to determine the best diet plan for managing blood sugar levels.

Carbohydrates have a direct impact on blood glucose

The type and amount of carbohydrates consumed can significantly affect blood glucose levels. Carbohydrates are broken down into glucose relatively quickly, which can lead to rapid increases in blood sugar levels. Simple carbohydrates, such as sugars, are broken down more rapidly by the body and can cause a faster rise in blood sugar. On the other hand, complex carbohydrates, such as starches, take longer to break down and result in a slower increase in blood sugar.

The glycemic index is a tool used to rank carbohydrates based on how quickly and significantly they raise blood sugar levels. Foods with a high glycemic index, like white bread, can cause substantial fluctuations in blood sugar, while those with a low glycemic index, like whole oats, lead to a more gradual rise. Consuming a diet high in high-glycemic-index foods can increase the risk of type 2 diabetes, heart disease, and weight gain. Therefore, it is crucial for individuals, especially those with diabetes, to be aware of their carbohydrate intake and how it affects their blood glucose levels.

Additionally, the quality of carbohydrates is more crucial to overall health than the quantity consumed. Choosing high-fibre, whole-grain foods instead of refined carbohydrates can improve heart health and reduce the risk of certain cancers. Fibre helps maintain healthy blood glucose and cholesterol levels and is associated with a lower risk of cardiovascular disease. Thus, selecting high-quality carbohydrates and monitoring portion sizes can help manage blood glucose levels effectively.

Insulin resistance and diabetes

Insulin resistance is a complex condition in which the body does not respond normally to insulin, a hormone produced by the pancreas that is essential for regulating blood sugar levels. Insulin resistance can lead to prediabetes and type 2 diabetes if left untreated.

Under normal circumstances, when you eat food, it is broken down into glucose (blood sugar), which enters your bloodstream. This signals your pancreas to release insulin, which helps glucose enter your muscle, fat, and liver cells to be used for energy or stored for later. Insulin also signals the liver to store extra blood sugar as energy for later.

However, in people with insulin resistance, the cells in the muscles, fat, and liver don't respond well to insulin. As a result, the pancreas produces more insulin to try to overcome the increasing blood glucose levels. This is called hyperinsulinemia. Over time, the pancreas can't keep up, and blood sugar levels continue to rise, leading to prediabetes and type 2 diabetes.

Several genetic and lifestyle factors contribute to insulin resistance. Excess body fat, especially around the belly, and physical inactivity are believed to be the main contributing factors. A diet high in processed, high-carbohydrate foods and saturated fats can also lead to insulin resistance, as it causes blood sugar spikes that put extra stress on the pancreas.

To prevent or manage insulin resistance, lifestyle changes such as a healthy diet, regular physical activity, and weight loss can help increase insulin sensitivity and decrease insulin resistance. A well-crafted ketogenic diet may also be beneficial for enhancing metabolic flexibility, reducing insulin levels, and managing glucose levels. However, it is important to monitor blood sugar levels closely when following a keto diet, as there may be fluctuations that require adjustments.

High fasting blood glucose

It is not uncommon for people on a keto diet to experience elevated fasting blood glucose levels. This phenomenon is called "glucose sparing" or "physiologic insulin resistance" and is a natural adaptation of the body to assure that glucose is present for organs that require it.

Adaptive Glucose Sparing

During a keto diet, the body switches from using glucose as its primary energy source to using fat, specifically ketone bodies created from fatty acids. This shift can cause an increase in fasting blood glucose levels as the body adapts to using fat for energy. The scientific term for this is "physiologic insulin resistance", which is different from "pathologic insulin resistance" seen in type 2 diabetes and other chronic conditions. Physiologic insulin resistance is likely a good thing and can be understood as the muscles being in "glucose refusal mode", preferring fat as fuel instead of glucose.

Insulin Levels

It is important to understand the relationship between glucose and insulin. When someone is prediabetic, has type 2 diabetes, or PCOS, their body may release higher and higher amounts of insulin just to keep blood sugar stable. As insulin resistance develops, blood sugars will eventually rise too high. On the other hand, someone on a keto diet for several months will be more insulin-sensitive and will only need small amounts of insulin to keep glucose in check.

Cortisol and Stress

Cortisol, also known as the stress hormone, has a direct impact on glucose levels. Prolonged cortisol stimulation will raise blood glucose levels. This is because cortisol sends a message to the body to release glucose in preparation for a perceived threat. In modern times, this stress often goes unreleased, and the resulting surge of glucose energy can lead to prolonged higher glucose levels.

Glucose Meter Accuracy

It is important to be aware that glucose meters can give false readings. The US Federal Drug Administration allows home glucose monitors to have a variance of 15% in results. Technical reasons for false readings include dehydration, soap residue on fingers, and environmental conditions like high altitudes.

Latent Autoimmune Diabetes in Adults (LADA)

If your blood glucose continues to rise despite following a keto diet, there may be a potential issue of LADA, also known as type 1.5 diabetes. LADA is like type 1 diabetes in that antibodies attack insulin-producing cells, but it arises in adulthood. It is often misdiagnosed as type 2 diabetes. A low-carb keto diet is a successful way to manage blood sugar levels for individuals with LADA.

In summary, while elevated fasting blood glucose levels on a keto diet may be surprising, it is often a normal adaptation of the body. However, it is important to monitor other health metrics and consult with a healthcare professional to ensure overall health and well-being.

Glucose sparing

In glucose sparing, the body prioritises glucose for tissues with an absolute requirement for it, such as the brain. This results in muscle tissue "refusing" glucose in order to keep it available for the brain, leading to a slight elevation in blood glucose levels. This is a healthy and normal response to a very low-carbohydrate diet and is not a cause for concern.

The dawn phenomenon, where blood glucose rises in response to surges of cortisol and other hormones in the early morning, can also contribute to elevated fasting blood glucose levels in people on a ketogenic diet. However, overall glucoregulation is typically improved, and glucose levels throughout the day are usually within the normal or low-normal range expected on a ketogenic diet.

It is important to distinguish between physiological insulin resistance, or glucose sparing, and pathological insulin resistance. Physiological insulin resistance is a likely positive adaptation of the body to a low-carbohydrate diet, whereas pathological insulin resistance is a negative condition associated with type 2 diabetes and other chronic conditions.

To fully understand the context of elevated fasting blood glucose, it is important to consider multiple measurements and assessments of metabolic health and glucoregulation, such as haemoglobin A1c (HbA1c) and HOMA-IR (homeostatic model assessment of insulin resistance). These provide a more comprehensive view of an individual's metabolic health and insulin sensitivity than fasting blood glucose alone.

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