The Vital Role of Glucose in the Body

The body breaks down carbohydrates, fats, and proteins into glucose, which it then uses to synthesize other sugars.

At the cellular level, the body uses glucose to make adenosine triphosphate or ATP, which fuels many essential cellular processes, including muscle contraction, cell growth and division, and DNA, RNA, and hormone synthesis.

One of the hormones responsible for regulating blood sugar is glucagon. Glucagon prevents glucose from dropping too low.

When the blood sugar drops due to prolonged fasting or increased activity, the pancreas produces glucagon, which triggers the liver to convert glycogen into glucose and release it into the blood to restore balance.

Insulin is another hormone secreted by the pancreas to regulate blood glucose. Unlike glucagon, insulin prevents blood glucose from getting too high.

It does this in a few ways. One way is by promoting the storage of glycogen in the liver. Insulin also promotes glucose uptake in the muscles and converts it into triglycerides for storage as fat.

There are many other hormones involved in maintaining proper glucose levels. The pituitary gland produces adrenocorticotropic hormone or ACTH, which stimulates the adrenal glands to release cortisol. In times of stress, cortisol triggers the liver to release glucose.

Epinephrine increases glucose output from the liver and decreases the glucose-lowering effects of insulin. Thyroxine raises the blood sugar by increasing absorption in the intestines, and growth hormone increases blood sugar by inhibiting the liver from storing glucose and affecting the action of insulin. You can see how one of these hormones out of balance could have a significant effect on the body.

Hyperglycemia is elevated blood glucose. This issue leads to many problems in the body, including peripheral nerve damage, oxidative stress, poor wound healing, coronary artery disease, and chronic kidney disease.

Hyperglycemia occurs when the body does not have enough insulin or it stops responding to it properly. Major risk factors for hyperglycemia include diabetes, obesity, high blood pressure, and polycystic ovary disease.

Hypoglycemia or low blood sugar is common in people taking medication for diabetes, but dangerously low blood sugar is less common.

Symptoms of low blood sugar include anxiety, tremors, palpitations, and hunger. If untreated, hypoglycemia can lead to seizures, coma, and death. People at risk include those with type 1 diabetes, anyone taking medication to treat diabetes, and people with a history of low blood sugar.

Type 1 diabetes is an autoimmune disease that affects the pancreas. Specifically, it destroys the beta cells in this small organ that produce insulin, allowing the blood glucose to get dangerously high.

Early symptoms of diabetes usually appear in childhood and include extreme thirst, excessive urination, weight loss, and fatigue. These symptoms can develop slowly or appear quickly.

Type 2 diabetes occurs when the beta cells in the pancreas cannot produce enough insulin to meet the body's needs, causing blood glucose to rise. Insulin resistance also plays a role in type 2 diabetes as the fat tissue on the liver and muscle is less sensitive to its effects.

This form of diabetes is the most common. People who are overweight and lead sedentary lifestyles are most at risk of developing type 2 diabetes.

There are a few ways to check blood glucose levels. A glucose meter is the easiest and most common and involves applying a drop of blood from a finger stick onto a test strip and then inserting the strip into a meter.

Blood glucose can also be obtained from a blood sample sent to a lab, but this method is not convenient for frequent monitoring.

Timing is an important factor when testing blood glucose. Glucose levels are the lowest right before meals or after fasting. Generally, the most accurate results are obtained in the morning after fasting overnight.

Normal blood glucose is under 100 mg/dL when fasting (first thing in the morning) or under 140 mg/dL two hours after eating. A fasting blood glucose greater than 125 mg/dL or 180 mg/dL two hours after eating indicates hyperglycemia. Hypoglycemia is blood glucose under 70 mg/dL, but symptoms may not occur until glucose is less than 55 mg/dL.