Why Do Diabetics Need Insulin?

hormone produced in the pancreas affects blood sugar levels

By Jonny Lupsha, Wondrium Staff Writer

Insulin is one of the most well-known hormones found inside living creatures. It has many functions vital for our bodies’ growth and development. How does insulin help the human body?

Woman checking blood sugar level due to diabetes
When the pancreas can’t produce sufficient insulin to maintain stable blood sugar levels due to a lack of physical activity and being overweight or obese, type 2 diabetes can develop. Photo by fizkes / Shutterstock

Our bodies produce the hormone insulin to serve several purposes, from regulating blood sugar levels to storing fat. Insulin also helps us grow additional muscle mass. More than 37 million Americans have type 2 diabetes, which means their cells don’t respond properly to insulin. Approximately 8 million of them need insulin shots to help maintain their blood sugar levels.

The state of California recently sued the biggest companies of the insulin market, accusing them of price gouging insulin. Despite a cap on insulin being part of the Inflation Reduction Act that was signed into law in August, many Americans still struggle to afford insulin. Why do we need insulin so badly? In his video series Changing Body Composition through Diet and Exercise, Dr. Michael Ormsbee, Associate Professor in the Department of Nutrition, Food, and Exercise Sciences at Florida State University, examines the hormone and its functions.

What Does Insulin Do?

“Insulin acts on the liver, fat tissue, and muscles, and is one of many hormones required for human growth and development,” Dr. Ormsbee said. “Insulin’s main function is to help regulate blood sugar levels. After you eat and your blood sugar begins to rise, the beta cells of your pancreas secrete insulin, which helps take glucose out of your blood and put it into the cells where it can be stored or used as energy.”

Insulin also releases signals to your brain that you’ve been fed, causing you to feel full. Since insulin is a “storage hormone,” it wants to store sugar and fat. When insulin gets released, it activates lipoprotein lipase (LPL), an enzyme that moves fat into fat cells and inhibits fat breakdown. In simple terms, this helps humans have a kind of “storage depot” to draw energy from when we’re not eating.

“Insulin has another role, too—it can increase your ability to add muscle mass,” Dr. Ormsbee said. “This is because insulin-stimulated glucose uptake into muscle cells also enhances muscle protein synthesis by increasing the transport of amino acids into your muscles. So, when insulin is released, you essentially go into storage mode rather than burning mode and turn off your ability to use fat as a fuel.”

How Does Your Diet Affect Insulin Levels?

Since insulin is so closely tied into our nutrition, it’s no surprise that what we eat affects our bodies’ insulin production, as well. There’s even a metric called the glycemic index that measures the relative amount that any food raises your blood glucose level, which can help you predict your body’s insulin response.

“Very high carbohydrate meals tend to raise insulin levels to the highest level,” Dr. Ormsbee said. “The higher the glycemic index of the carbohydrate, the more it will raise insulin. This acute rise in insulin is normal and really not a problem: Your body handles it, and then blood glucose and insulin will return to lower concentrations.”

This isn’t limitless, though. When we regularly overload our bodies with high-carb meals, our insulin levels will remain higher than they should. Doing this over a long period of time can lead us to become insulin resistant, which is when our cells don’t respond properly to insulin. Then, our blood sugar is not well-controlled and our body overcompensates by producing more and more insulin via the pancreas to lower blood sugar levels.

When the pancreas can’t keep up, the blood sugar levels stay too high, leading to prediabetes and to type 2 diabetes.

Changing Body Composition through Diet and Exercise is now available to stream on Wondrium.

Edited by Angela Shoemaker, Wondrium Daily