Updated: Oct 31, 2022
Insulin. We have heard this word discussed throughout the program as an important part of The Livy Method process. We are encouraged to eat high quality foods, support our bodies with supplements if we can, approach eating to the point where we feel satisfied, incorporate some exercise or activity to move our bodies, manage our stress levels, and prioritize having good, restful sleep. All of these things will help not only improve our health, wellness, and promote weight loss, but will also help to naturally lower our insulin levels.
In this science post we will be taking a deeper dive in the exploration of this highly discussed hormone. So, what exactly is insulin, and what exactly is its role in the body?
Insulin is a very important hormone in digestion, and has a huge role in helping to process and store the energy provided from the food that we eat! It is composed of 51 amino acids and for this reason is called a peptide hormone (hormones that are composed of small chains of amino acids). It plays an important part in glucose regulation, cell growth, and metabolism.
Insulin was previously believed to be solely produced by special cells in the pancreas called beta cells; however, recent evidence has shown that low concentrations are also found in certain neurons of the central nervous system!
As we have discussed in previous articles, the pancreas plays a principal part in digestion by producing hormones and enzymes that are crucial to the digestive process. However, this amazing organ also has a critical role in using and storing the energy (in the form of glucose) that it had just helped to break down and process, from the foods that we just ate!
So, let’s back up this conversation a bit further. Let’s recap the basics of digestion and then discuss how the foods we eat are processed for their energy.
Short recap on digestion
All parts of our body need energy to work, and this energy comes from the food we eat. As discussed, our bodies begin the digestive process when we think about and use our senses when preparing our food. When we ingest it, it begins mixing in with the saliva and enzymes in our mouths through the process of chewing. Then, the food bolus enters the stomach by way of the esophagus, and begins mixing with fluids (containing acids and enzymes) in the stomach. As the stomach churns and mixes, the food is processed and broken down further, resulting in reducing the carbohydrates we eat (sugars and starches) to their simplest form, a sugar called glucose. Proteins are broken down into amino acids and fat is broken down into fatty acids to be used by the body.
Glucose is the main energy source for our body’s cells, and what keeps us functioning at all times whether it is when we are active and moving, resting and sleeping, it keeps our heart beating and lungs breathing. It is what allows all the organs and cells in our bodies to do what they need to do to keep us alive!
So, let’s break it down even further, let’s take a deeper look at what glucose actually is.
What is glucose?
Glucose is the simplest form of carbohydrates and only has one sugar molecule, which is called a monosaccharide. Other monosaccharides that may sound familiar include fructose, galactose, and ribose, which the body also processes or may produce for energy. To understand the differences, let’s look at all these in more detail!
Glucose comes from the Greek word for "sweet" (Watson, S., & DerSarkissian, C. 2020, June). As discussed, glucose is a type of sugar you get from the foods you eat, and is what your body uses for energy. You may have heard the terms blood glucose or blood sugar, which are often used to describe the amount of glucose measured in your blood as it travels through your bloodstream to your cells. This can be quantified in a lab blood test, and results can be measured in that moment in time as a blood sugar, as a “fasted” blood sugar (taking your blood sugar after not eating or drinking for 8-12 hours), and as an A1C [which measures the percentage of hemoglobin (a protein in your red blood cells) that are coated in sugar, and can analyze your average blood sugar for the last 3 months].
Glucose is the most common monosaccharide found in nature. Some plants store glucose in linked chains. These chains are called starch. Common starch-containing foods include corn, potatoes, rice, and wheat. Glucose monosaccharides are also found naturally in some foods. The most concentrated whole food source of glucose monosaccharides are honey, followed by dried fruits such as dates, apricots, raisins, currants, cranberries, prunes and figs.
Most of the cells in your body use glucose along with amino acids (the building blocks of protein) and fats for energy. However, glucose is the main source of fuel for your brain. Nerve cells and chemical messengers located there need it to help them process information, and having access to glucose is very important for overall brain function. Your brain uses about 60% of the glucose that our bodies use. However, glucose does not always have to come immediately from foods and beverages. Glucose is also generated by the body to ensure that we always have the amount that is needed. One way that this is achieved is by breaking down something called glycogen, in order to free up the glucose it contains.
Glycogen is released by an important hormone called glucagon. When the body does not need to use glucose for energy, it is stored in the liver and muscles by insulin. This stored form of glucose is made up of many connected glucose molecules and is the glycogen. When the body needs a quick boost of energy or is not getting glucose from food, glycogen is broken down to release glucose into the bloodstream to be used as fuel for the cells. Your body can store enough glycogen in order to keep you fueled for about a day.
The body can also produce glucose through a process called gluconeogenesis. This process occurs when the body (mainly the liver, followed by the kidneys, and to a lesser extent the small intestine) makes glucose from non-carbohydrate sources which include lactate (what our bodies produce during exercise), glycerol (is produced when fats are digested, can be used for energy or stored in adipose tissue) and amino acids. Gluconeogenesis occurs when glycogen stores become low and glucose consumption is too low or nonexistent, such as during periods of starvation or prolonged fasting. Although the body has enough glycogen stored in the muscles and liver to last about a day, after about 14 hours in a fasted state it will begin to increase its percentage of gluconeogenesis, generating energy in increased ratios as time goes on (Chourpiliadis, C., & Mohiuddin, 2021).