What is Insulin?


Essential for life, the hormone insulin regulates many metabolic processes that provide cells with needed energy. Understanding insulin, what insulin does, and how it affects the body, is important to your overall health.

Tucked away behind the stomach is an organ called the pancreas, which produces insulin. Insulin production is regulated based on blood sugar levels and other hormones in the body. In a healthy individual, insulin production and release is a tightly regulated process, allowing the body to balance its metabolic needs.

What does insulin do?

Insulin allows the cells in the muscles, fat and liver to absorb glucose that is in the blood. The glucose serves as energy to these cells, or it can be converted into fat when needed. Insulin also affects other metabolic processes, such as the breakdown of fat or protein.

Problems with insulin production or use

The most common problem associated with insulin is diabetes. Diabetes occurs when the body either does not secrete enough insulin or when the body no longer uses the insulin it secretes effectively.

Diabetes falls into two categories: Type 1 diabetes occurs when the pancreas cannot produce insulin sufficiently to meet its own needs. This commonly occurs in children, and while an exact cause has not been found, many consider it to be an autoimmune disease. Some symptoms of type 1 diabetes include tiredness, increased urination and thirst, and problems with vision.

Type 2 diabetes is more commonly associated with adults and lifestyle choices. People with type 2 diabetes will produce insulin but often not enough for their body's needs. They may also struggle to use the insulin they produce effectively. Patients may not know they have type 2 diabetes until they have an annual checkup, as symptoms tend to be mild until the disease has become severe.

When the body does not produce enough insulin or use it efficiently, blood sugar levels build in the body. Also, the body's cells do not receive the energy they need from glucose, so the patient may struggle with fatigue. When the body turns to other tissue, like fat or muscle, for energy, weight loss may occur.

High blood sugars are a common symptom of diabetes, but patients who are treating their diabetes with insulin injections may inject too much insulin on occasion. This causes the body's cells to take too much glucose from the blood, leading to a low blood sugar episode. Low blood sugar can cause confusion, dizziness and fainting. Because nerve cells rely entirely on glucose for energy, low blood sugar can also trigger a nervous system response.

Questions to ask your doctor

If you suspect that you are struggling with insulin levels and production, you must consult your doctor for help. You need to have your insulin levels tested. If you are diagnosed with diabetes, you will need medical oversight to manage the condition. Questions to ask your doctor include:

  • How can I manage blood sugar and insulin levels?
  • What type of monitoring do I need?
  • What lifestyle changes can make blood sugar levels more stable?
  • How can I prevent diabetes from developing if I am at risk but have not developed the disease?
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