The pancreas is a digestive system organ with two distinctive roles. One of its jobs is to produce some of the enzymes necessary for breaking down carbohydrates, proteins, and fats into their basic nutrients.
The other important task performed by the pancreas is the production of several hormones which are needed for a variety of metabolic functions in the body. This article focuses on the endocrine (hormone-producing) aspect of the pancreas and how it affects fat burning and storage.
The endocrine function of the pancreas is performed in tiny clusters of cells known as islets of Langerhans. There are five types of cells in the islets.
Each cell type secretes a different hormone:
- Alpha cells are responsible for secreting the hormone glucagon;
- Beta cells secrete insulin;
- Delta cells secrete somatostatin;
- PP cells secrete pancreatic polypeptide.
- Epsilon cells produce ghrelin
These hormones are released into the blood stream via capillaries located in close proximity to the islets of Langerhans. Only insulin and glucagon are directly involved in fat burning and storage.
The main purpose of insulin is to transport glucose (which is derived from carbohydrates and is the main source of fuel for the body) into the cells, where it is either used right away or stored in the muscles as molecules called glycogen for later use.
The energy stored as glycogen is used to fuel the muscles during physical activity; when glycogen stores are depleted – whether through intense exercise or overnight, during sleep – they need to be replenished; this is accomplished by consuming carbohydrates in the form of starches or sugar.
However, when the glycogen stores are full and additional carbohydrates are consumed, insulin is forced to store the resulting glucose as fat, or adipose tissue.
Insulin, Obesity and Diabetes
When carbohydrates are frequently consumed in excess, insulin levels in the blood remain chronically high, leading to insulin resistance by the cells of the body and causing blood sugar to be stored as fat rather than used for energy. Over time, these conditions can result in obesity, which in turn may lead to Type II diabetes –a serious medical condition with long-term, life-threatening health consequences.
Although glucagon, like insulin, is secreted by the pancreas, it functions in essentially the opposite manner. When the levels of glucose in the blood are low, glucagon is triggered and stimulates the mobilization of glycogen stores to provide fuel for the body. Once the glycogen stores are used up, glucagon triggers a process known as gluconeogenesis, the conversion of fats into glycogen. The glycogen is then converted by glucagon to glucose, which can then be used for energy.
Keeping the Balance
To simplify this complex chain of events, you can follow them to the end result: insulin stores energy in fat cells, and glucagon burns fat for energy. Under ideal circumstances, these two processes balance each other out; however, numerous factors can affect the equation.
Whether you are overweight or not, whether you get plenty of exercise or lead a sedentary lifestyle, and the types and quantities of the foods you eat can all determine whether glucagon and insulin work together correctly.
When insulin and glucagon levels are in a state of imbalance, you may experience a number of problems: food cravings, drastic changes in blood sugar levels, accumulation of adipose tissue, mood swings and muscle loss are just some of the effects of insulin and glucagon imbalances.
To avoid these problems, make sure that you consistently eat a healthy diet; include plenty of fresh fruits and vegetables, whole grains, heart-healthy fats and lean protein in your meal planning. Avoid fasting and crash diets, and make physical activity a part of your daily routine. If you are overweight, talk to your doctor about the best weight loss program for your condition. With proper management, you can ensure optimum pancreatic function.