Blood Glucose 101

Being a diabetic patient, you must approach glucose with reverence, respect, and caution. Glucose molecules are responsible for all the devastating chronic complications of diabetes. They bind to proteins and damage them. These damaged proteins, with glucose attached to them, are called advanced glycation end products (AGEs).

In many countries, doctors and diabetic patients measure the blood glucose levels in milligrams per deciliter (mg/dL). However, in some countries, blood glucose measurement units are millimoles per liter (mmol/L). To convert a reading from mg/dL to mmol/L, divide the value by 18.

In the context of diabetes control, the goal is to achieve and sustain healthy blood glucose levels. For adults, the recommended target is 83 mg/dL ± 10 mg/dL. For diabetic children through adolescence, the target is slightly lower at 73 mg/dL ± 10 mg/dL, i.e., 63 to 83 mg/dL. Read more about it here.

Organized medicine recommends that people with diabetes maintain higher blood glucose levels than their healthy peers. We discuss the rationale behind it below.

What else you should remember about glucose:

1. Glucose is a carbohydrate, along with fructose and galactose.
2. Carbohydrates dissolve readily in water and, therefore, in blood and saliva. It sets them apart from fats and cholesterol.
3. The fructose molecule closely resembles glucose. However, its metabolic fate in the human body is entirely different. Dietary fructose is far from harmless. In some respects, it may be even more harmful than glucose.
4. Glucose is a vital fuel for our cells and tissues. However, unlike proteins, fats, and many essential nutrients, a deficiency of glucose or other carbohydrates in the diet is neither harmful nor dangerous.
5. The body tries to quickly clear excess glucose from the blood to prevent the formation of advanced glycation end products. When its glucose storage is replete, it has no choice but to convert the surplus into fat.
6. If someone doesn’t eat carbohydrates, their body makes glucose from proteins — specifically, from their amino acids.
7. The process of producing glucose from amino acids is called gluconeogenesis. It ensures that blood glucose levels don’t drop to zero, even if you follow a strict low-carb diet.
8. Your body can’t turn fatty acids into glucose, so the fats you eat barely affect your blood sugar. But protein is a different story. Dietary protein raises your blood sugar levels. However, it happens slowly, and you can manage it pretty well.
9. People with type 2 or type 1 diabetes — including children — should aim to maintain blood sugar levels no higher than those of their healthy peers. The methods in this book can help you achieve that.

Now, let’s break down some of those points in more detail.

How Humans Use Glucose and Its Substitutes for Energy

Glucose is a vital component among the myriad substances present in human blood. It serves as the principal, though not exclusive, source of energy for our body tissues. For your cells to burn glucose as fuel, insulin must be present to let it in. Notably, brain cells possess the unique ability to absorb glucose even without the assistance of insulin.

Our ancestors often went hungry—sometimes for weeks or even months. Because of that, you and I have inherited a remarkable ability to cope without a steady supply of glucose from food. People who could not adapt to food shortages failed to survive the many famines of the past. They didn’t pass on their genes. Your ancestors were lucky, so you can follow a low-carb diet safely and even thrive on it, consuming little to no glucose. Unfortunately, we are not so great at handling an excess of carbohydrates. It is a big reason behind today’s epidemics of obesity and type 2 diabetes.

Understanding Gluconeogenesis and Fat Burning

Your body obtains glucose from the carbohydrates you consume. In the absence of carbohydrates, your body has the remarkable ability to synthesize essential glucose from proteins. Even if you don’t eat a single gram of carbohydrates, your body can still produce vital glucose by converting proteins. As I told you above, this process is called gluconeogenesis.

In the absence of dietary glucose influx, trying to meet all the body’s energy needs by breaking down its protein is a bad idea. It can quickly lead to the damage of vital organs, not to mention muscle destruction. To preserve protein, as soon as gluconeogenesis kicks in, your body also starts burning fat for fuel. It breaks down fatty acids into smaller molecules called ketone bodies or ketones. These small molecules mainly provide energy to your brain when glucose is in short supply. Ketone bodies are also linked to a dangerous diabetes complication called ketoacidosis. You would better take some time to learn more about it.

The human body cannot produce significant amounts of glucose from fats. Strictly speaking, it does manufacture a little bit of glucose from the fats you eat. However, practically speaking, the fats you ingest barely move your blood sugar levels. While they may slightly slow down the absorption of proteins and carbohydrates, the effect is negligible.

Glucose Extraction: What Happens After You Eat Carbs

The human body possesses remarkable speed and efficiency in converting the carbohydrates we consume into glucose. This process initiates in the mouth, where an enzyme amylase found in saliva begins the breakdown. Interestingly, glucose can be absorbed into the bloodstream directly from the mouth, even without swallowing chewed food.

For individuals with diabetes, this rapid conversion of carbohydrates into glucose poses a challenge. Despite claims made by organized medicine, relying on insulin injections does not effectively address this swift process. The only suitable solution is adopting a low-carbohydrate diet. It is essential for effectively managing impaired carbohydrates metabolism.

Glycogen and Fat: Our Glucose Storage Systems

Above, you learned that glucose enters the bloodstream almost immediately from the carbohydrates you eat. However, our bloodstream can only accommodate a limited amount of this substanceat any given time. For healthy adults, it is about one heaping teaspoon. Children have an even lower capacity.

When enough insulin is available, the body clears excess glucose from the blood quickly. This step is crucial in preventing diabetic complications. The goal is to prevent glucose from sticking to proteins by mistake. The body binds glucose molecules together into long structures. We call those structures glycogen. They serve as a reserve fuel source. The liver and muscles store glycogen.

The liver and muscles have a limited capacity to accumulate glycogen. In adults, the typical total capacity of glycogen stores ranges from 250 to 400 grams. Individuals who lead a sedentary lifestyle typically have their glycogen stores filled to their maximum capacity. In that case, the body has no choice but to convert the ingested glucose into fat with the assistance of insulin. After conversion, the adipose tissue stores that fat. While accumulating fat deposits is easy, shedding them can be challenging.

This point is worth repeating because it’s critical. When you eat plenty of carbohydrates, your body has no choice but to turn excess glucose into fat. That glucose gets converted into triglycerides, which then get stored in your fat tissue. It’s the lesser of two evils. Yes, obesity is harmful—but the formation of advanced glycation end products is much worse.

The body converts glucose into fat only when there’s enough insulin to make that happen. But, for people with diabetes, insulin is often in short supply. When that’s the case, the excess glucose stays in the blood far too long. It starts sticking to proteins, damaging them—and that’s how chronic diabetes complications develop over time, eventually leading to disability and early death.

You might want to bring this information up with your endocrinologist. The conversation could reveal a lot about how competent they are. From what I’ve seen, most certified doctors don’t seem to grasp that excess glucose gets converted into fat. They know that obesity is incredibly hard to reverse because many of them struggle with it personally. But despite all their biochemistry training, they often miss the basic fact that body fat is formed from the carbs people eat.