What Does Insulin Do?

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What Is Insulin & How Does It Work?

The word “insulin” can instill fear in many people who have or who are at risk for diabetes. Some of the beliefs around insulin are that if you have to take it, you’ll go blind or lose a limb. Or that insulin causes you to gain weight. Or that it means your diabetes is worsening. While these beliefs are understandable, the reality is that they’re not true. In fact, insulin is a life-saving medication: without it, people with type 1 diabetes wouldn’t be alive. The discovery of insulin is so important that it’s often called one of the greatest medical developments of the 20th century. Let’s delve into insulin and learn more about how truly amazing it is!


What is type 1 diabetes?

Type 1 diabetes is an autoimmune disorder in which the immune system attacks and destroys the insulin-producing beta cells in the pancreas. As a result, the pancreas produces little or no insulin. Type 1 diabetes is also characterized by the presence of certain autoantibodies against insulin or other components of the insulin-producing system such as glutamic acid decarboxylase (GAD), tyrosine phosphatase, and/or islet cells.

When the body does not have enough insulin to use the glucose that is in the bloodstream for fuel, it begins breaking down fat reserves for energy. However, the breakdown of fat creates acidic by-products called ketones, which accumulate in the blood. If enough ketones accumulate in the blood, they can cause a potentially life-threatening chemical imbalance known as ketoacidosis.

Type 1 diabetes often develops in children, although it can occur at any age. Symptoms include unusual thirst, a need to urinate frequently, unexplained weight loss, blurry vision, and a feeling of being tired constantly. Such symptoms tend to be acute.

Diabetes is diagnosed in one of three ways – a fasting plasma glucose test, an oral glucose tolerance test, or a random plasma glucose test – all of which involve drawing blood to measure the amount of glucose in it.

Type 1 diabetes requires insulin treatment for survival. Treatment may also include taking other drugs to prevent kidney damage or to treat diabetes-related conditions such as high blood pressure.


What exactly is insulin?

Insulin is a hormone. It’s made in the beta cells of the pancreas, and one of its main roles is to help regulate, or control, your blood sugar. When there’s enough insulin in the body, it helps to keep your blood sugar from going too high. In people who don’t have diabetes, blood sugars are very carefully and tightly controlled, staying within a safe and healthy range.

After a person without diabetes eats a meal or a snack, the pancreas releases insulin. The insulin then signals muscle, fat and liver cells in the body to absorb glucose (sugar) from the bloodstream to be used for energy. In this sense, insulin is like a key that unlocks the doors of the cells to allow glucose to enter. You can also think of insulin as a “storage” hormone, since when there’s more glucose than the body needs, insulin helps the body store that excess glucose in the liver to be used at a later time. Insulin also signals the liver to stop releasing glucose into the bloodstream.

Insulin also helps shuttle amino acids (from protein digestion) and fatty acids (from fat digestion) into cells.

What happens to insulin in type 1 diabetes?

If you have type 1 diabetes, you must take insulin, either by injection or by insulin pump, to survive. Why? Type 1 diabetes is an autoimmune disease that destroys the beta cells in the pancreas. This means that the body can’t produce insulin (or at least enough of it). When this happens, the body literally can’t fuel itself, and it will start to use protein and fat stores for energy. This may seem OK, but blood sugar levels climb dangerously high. In addition, a serious condition called diabetic ketoacidosis (DKA) can set in, which, if not treated, can be fatal. Hopefully you can see why insulin is literally a life-saving medicine for those with type 1 diabetes.

Is there an insulin “pill”?

Some people are scared of taking insulin because it has to be injected or infused. Injections and infusions mean needles, and if you have a fear of them, it’s understandable that you’re not going to be too keen on insulin injections. (There is an inhalable insulin available, but that’s an ultra-rapid-acting insulin; a longer-acting insulin is usually needed, and that must be taken by injection.)

You might be wondering why scientists haven’t come up with an insulin pill. It would be so easy to swallow insulin in a pill or capsule form, wouldn’t it? Unfortunately, at this time, no oral form is available. But it’s not for lack of trying: Researchers have been working on this for at least 80 years. The problem is that insulin, as mentioned, is a hormone, and most hormones are types of proteins. The digestive tract breaks down proteins, and insulin is no exception. Insulin in a pill form wouldn’t make it through the digestive tract to do its job of regulating blood sugars. In addition, insulin would have a tough time passing through the lining of the intestines into the bloodstream. But let’s not give up hope: Various drug companies are busy plugging away at this issue in hopes of coming up with an oral insulin that would do away with injections.

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