What is blood glucose level?
Blood glucose level is the amount of glucose (sugar) in the blood. It is also known as serum glucose level. The amount of glucose in the blood is expressed as millimoles per litre (mmol/l).
Normally, blood glucose levels stay within narrow limits throughout the day (4 to 8mmol/l). But they are higher after meals and usually lowest in the morning
Most dietary eventually ends up as glucose in the blood. Excess glucose is converted to glycogen for storage by the liver and skeletal muscles after meals. Glycogen is gradually broken down to glucose and released into the blood by the liver between meals. Excess glucose is converted to triglyceride for energy storage.
Glucose is a major source of energy for most cells of the body. Some cells (for example, brain and red blood cells), are almost totally dependent on blood glucose as a source of energy. The brain, in fact, requires that glucose concentrations in the blood remain within a certain range in order to function normally. Concentrations less than about 30 milligrams per deciliter (mg/dl) or greater than about 300 mg/dl can produce or .
The major hormone regulating glucose concentration in the body is insulin (although other hormones such as , epinephrine, and cortisol also affect it).
Carbohydrates are an optimal source of energy. They can be quickly used as fuel, and provide quick bursts of energy. They are 'nutrient' dense rather than 'energy' dense, and supply 4 calories per gram (fat supplies 9 calories per gram). Carbohydrates fulfill three important roles in the body. Their most critical function is in maintaining blood glucose levels, a ready supply of fuel for body tissues. Though skeletal muscles use the greatest quantity, the brain and central nervous system are dependent upon glucose to function effectively. For example, low blood glucose levels have been associated with negative mood states. This may be particularly evident in individuals with blood sugar disorders such as hypoglycemia and diabetes.
Glucose is also converted to glycogen for storage by the liver and muscle cells. Liver glycogen serves as an immediate energy reservoir, available to replenish falling blood glucose levels. There is another possible destination of glucose produced from excess carbohydrates in the diet - one that most people don't usually appreciate. And that is the fat cell. While carbohydrates are not "'fattening' consuming more than the body's immediate energy needs leads to fat storage. Once transformed into fat, there is minimal conversion back to glucose.
But we can't just live on carbohydrates. Protein, for instance, is essential for proper immune system function, tissue growth, cell maintenance and repair. Protein also supplies 4 calories per gram, but using it for the body's energy needs is not its most important function.
Protein is also essential for water balance in the body. This is one reason why carbohydrates and proteins must both be consumed, and why their intake must stay in balance. For example, each pound of carbohydrate stored in the body results in the retention of three pounds of water. Therefore, protein is necessary to help regulate excessive water retention.
There is also a complex relationship between carbohydrates and proteins in maintenance of stable blood glucose levels. As mentioned, carbohydrates raise blood glucose levels - sometimes very rapidly. Protein will influence the rate of carbohydrate absorption to allow slower, more gradual increases in the blood glucose. In addition, protein can be transformed slowly into glucose as well - in essence providing a baseline level of blood glucose for the body. This will help prevent rapid increases or sudden falls in blood glucose that affect mood, energy levels, and fat storage.
MORE ABOUT THINGS THAT RAISE BLOOD GLUCOSE LEVEL:
FOOD & DIET :You body breaks down the carbohydrates in food into glucose. When you eat, the amount of glucose in your blood rises. Different foods contain different amounts of carbohydrates, so the amount of glucose each adds to your blood will vary. Over time you’ll be able to anticipate how much certain foods will make your blood glucose levels, rise, and react accordingly. If you are on a low-fat diet, remember: you still have to pay attention how many carbohydrates you are eating, or your blood glucose level may jump. Also, some “low-fat” and “no-fat” foods contain modified forms of carbohydrate used as emulsifiers or bulking agents that can push up your blood sugar. Ask your dietitian what ingredients you should watch out for.
STRESS: Stress produces hormones that cause glucose levels to skyrocket. When you’re following your doctor’s instructions to the letter and still find your blood glucose levels are too high, stress may be to blame.
ILLNESS : Sickness often raises blood glucose level because the liver releases extra glucose in response to illness, and the body also releases hormones that counteract the effects of insulin. In addition, some cough and cold medicines contain ingredients that raise blood glucose levels (and blood pressure).
EXERCISE : If you have type 1 diabetes and don’t have enough insulin aboard, exercise can make your blood sugar level rise. During moderate to vigorous exercise, nerves signal the liver to release stored glucose. If you don’t have enough insulin to cover the extra sugar in your blood, ketoacidosis can result. That’s why you should check your blood glucose levels both before and after you work out to make sure they’re O.K.
DAWN PHENOMENON: Very early each morning, the body releases hormones that wake you up and tell the liver to release stored glucose to give you energy to start the day. These hormones also inhibit insulin. The result is that glucose level rises between 4 a.m. and 8 a.m., reaction known as the dawn phenomenon. Dawn phenomenon is the reason why blood glucose levels are often unusually high when you wake up. If your glucose levels are high each morning, talk with your health care team. You may need to modify the dose or type of insulin you take before bed. You may need to get up around 3 a.m. and take insulin. Or you may need to eat less at breakfast or increase your morning insulin dose.
MENSTRUATION : in some women, cyclic changes in blood levels of estrogen and progesterone wreak havoc on blood glucose around the time of menstruation. One survey of 400 women showed that nearly 70 percent had problems controlling their glucose levels within a week before their periods. Depending on the individual, sometimes blood glucose may rise too high, or fall too low.
WHAT SHOULD YOU DO IF YOUR BLOOD GLUCOSE LEVELS TEND TO GO UP BEFORE YOUR PERIOD:
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Exercise a little more to help bring glucose levels down.
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Try to avoid extra carbohydrates.
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If you use insulin, ask your doctor about gradually increasing your dose.
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Consult your health care team.
CONTRACEPTIVES : Birth control pills and the IUD work by altering hormone concentrations in the blood. This, in turn, can affect your blood glucose levels. In some women these devices can increase insulin resistance. On the other hand, one type of birth control pill-a monophasic pill- which releases a steady amount of hormones throughout your cycle may even help keep your blood glucose swings to a minimum. In any event, your health care team can help you choose the birth control method that’s best for you.
PREGNANCY: women who use insulin often have to increase their insulin dose over the course of pregnancy to maintain tight control of glucose levels. Some women need to increase their dose considerably, especially in the last trimester because pregnancy releases hormones that create insulin resistance. This increase in insulin resistance is normal. You and your health care team should decide how to change your insulin schedule and dose. After delivery, your blood glucose levels may swing unpredictably because your hormone levels and general body chemistry are still in flux. You may require less insulin for the first three to four weeks. If you find that keeping good blood glucose control is difficult, talk it over with your health care team.
