Blood glucose refers to the sugar that the bloodstream carries to all cells in the body to supply energy. A person needs to keep blood sugar levels within a safe range to reduce the risk of diabetes and heart disease. Blood glucose monitoring measures the amount of sugar that the blood is transporting during a single instant.
People obtain this sugar from their diet. The human body regulates blood glucose levels so that they remain moderate: Enough glucose to fuel the cells, but not enough to overload the bloodstream. The blood’s internal environment must remain stable to support vital bodily functions. Blood glucose levels change throughout the day. After eating, levels rise and then settle after about an hour. They are at their lowest point before the first meal of the day.
What is a healthy blood sugar level?
Health authorities consider a normal fasting blood sugar level to be below 99 milligrams per deciliter (mg/dL). In people with diabetes, the levels will change more. Instead of targeting a specific level, the aim of managing blood sugar is to keep the levels within a healthy range.
The American Diabetes Association recommends target levels of 70–130 mg/dL before eating for a person with diabetes. Within 2 hours of eating a meal, blood glucose levels should be less than 180mg/dL.
Which Organ Regulates Blood Sugar?
The pancreas is an elongated organ wide on one end and slender on the other end and measures about 25 centimeters in length. It has dual functions: it releases digestive enzymes, which play a role in digestion, and it secretes hormones.
Prevents High Blood Glucose
Insulin plays an integral role in preventing high blood sugar. After you eat a meal and your blood glucose rises, your pancreas senses your blood-sugar level. When the glucose in your bloodstream becomes high, the pancreas releases insulin into your bloodstream. A small clump of pancreatic cells called the ”islets of Langerhans,” manufacture insulin. Once the insulin is in your bloodstream, it allows your cells to absorb and use glucose as a fuel source.
Mediates Low Blood Sugar
When you consume more carbohydrates than your body needs at the time, your body stores the extra glucose as glycogen in the liver. The pancreas continuously monitors your blood sugar levels. When glucose is low, the pancreas releases the hormone glucagon. The glucagon triggers the liver to break down glycogen and converts it back to glucose. The stored glucose enters the bloodstream and raises blood glucose levels. This allows the body to keep blood sugar levels stable in between meals.
Blood Glucose Problems
In some cases, the pancreas is unable to produce enough insulin, which causes blood sugar to remain high. This is what happens in Type 1 diabetes. In Type 2 diabetes, the pancreas may produce insulin, but the tissues may become less sensitive in responding. This causes the pancreas to release more insulin, which can lead to a vicious cycle. The pancreas can over-react and release a large amount of insulin in relation to the amount of glucose in the blood.
How the liver regulates blood glucose
During absorption and digestion, the carbohydrates in the food you eat are reduced to their simplest form, glucose. Excess glucose is then removed from the blood, with the majority of it being converted into glycogen, the storage form of glucose, by the liver’s hepatic cells via a process called glycogenesis.
Glycogenolysis. When blood glucose concentration declines, the liver initiates glycogenolysis. The hepatic cells reconvert their glycogen stores into glucose and continually release them into the blood until levels approach the normal range.
However, when blood glucose levels fall during a long fast, the body’s glycogen stores dwindle and additional sources of blood sugar are required. To help make up this shortfall, the liver, along with the kidneys, uses amino acids, lactic acid, and glycerol to produce glucose. This process is known as gluconeogenesis. The liver may also convert other sugars such as sucrose, fructose, and galactose into glucose if your body’s glucose needs are not being met by your diet.
Ketones. Ketones are alternative fuels that are produced by the liver from fats when sugar is in short supply. When your body’s glycogen storage runs low, the body starts conserving the sugar supplies for the organs that always require sugar, including the brain, red blood cells, and parts of the kidney. To supplement the limited sugar supply, the liver makes ketones in a process called ketogenesis.
Ketones are burned as fuel by muscle and other organs in the body, and the sugar is saved for the organs that need it. Like glucose, the production of ketones in the liver is controlled by the hormone glucagon.
Dawn Phenomenon and Rebound Hyperglycemia. Blood glucose levels rise sharply in the early morning due to the release of certain hormones in the middle of the night. These counter-regulatory hormones, which include glucagon, growth hormone, epinephrine, and cortisol, increase the level of blood glucose by signalling the liver to release more glucose and by hindering glucose utilization throughout the body.
Overnight, the surge in the amount of growth hormone and cortisol released by the body effectively increases glucose production in the liver to prepare the body for activity during the day. For individuals without diabetes, these processes are balanced out by increased insulin secretion by the pancreas, which keeps blood glucose levels relatively stable.
But in people with type 1 diabetes, whose bodies are unable to produce insulin, and type 2 diabetes, where the liver’s response to insulin may not be sufficient to stop glucose production, changes in glucose metabolism during sleep can have a big impact on morning blood glucose levels.
In addition to the dawn phenomenon, there is another process that can cause high blood sugar in the early hours of the day.
Rebound hyperglycemia. Rebound hyperglycemia, the body’s rebound from low blood glucose levels at night, is also caused by the release of counter-regulatory hormones and represents the body’s defense mechanism against low blood sugar. The only way to tell the two phenomena apart is to check your blood glucose level in the middle of the night (around 3am) – a high level indicates you are experiencing the dawn phenomenon, while a low reading suggests rebounding hyperglycemia. Another name for rebound hyperglycemia is the Somogyi effect. ALSO READ: How to Use Chirata In Diabetes
