Metabolism of Glucose

Metabolizing glucose is a process our body undertakes to provide itself with needed energy. But first we have to consume the carbohydrates (sugars, starches and cellulose) that contain glucose units. And we also have to have an enzyme (insulin) present in our body to metabolize glucose (diabetics don't have this enzyme---or it doesn't work properly if they do).

Carbohydrates and Glucose Rings

• There are three types of carbohydrates that we consume: sugars, starches and cellulose.
  All three of these carbohydrates have what is known as glucose rings (units of glucose contained in them). While we get energy from all three---with some providing more glucose units than others---it is the simple sugars (the one actually called glucose) that provides our primary fuel source when metabolized.

Glucose: Simple Sugar and Starches

• Glucose, fructose, lactose and sucrose (table sugar) are examples of the carbohydrate known as "simple sugars." One of these simple sugars (glucose) is our main fuel source, but all the simple sugars (as well as starches and cellulose) contain glucose units used for energy too. Wheat, potatoes, rice, and corn are some examples of carbohydrate "starches" that contain glucose units.

Glucose: Cellulose

• Our other glucose energy source is cellulose, but we can't eat it directly. For example, wood is cellulose. And while termites and animals can eat it for energy, humans cannot. Although humans cannot eat cellulose as a food source, we can eat animals that do, providing us with cellulose benefits (fiber) and the resulting benefit of glucose units we get from its consumption.

Metabolism of Glucose

• These carbohydrate glucose units (molecules) enter our bodies, beginning the metabolism process. This process is achieved via two different methods. One includes the use of oxygen to metabolize the glucose molecules (aerobic metabolism) the other (anaerobic metabolism) does not.

  As the digested food begins to circulate in our bloodstream, our pancreas releases the enzyme insulin, which serves as a glucose "transporter." Insulin ushers the released glucose into all the cells that require it as an energy source.

Cells and Glucose Metabolism

• Once inside the cell, the glucose molecule is burned. If the cell contains oxygen, it is used to aid in this process. But if it does not, the process moves forward anyway. This then produces heat and adenosine triphosyphates (ATPs). The ATPs job, after production, is to store the energy for the cell until it has need of it.

Oxygen's Role in Metabolism

• Some cells do not contain oxygen in them (red blood cells), while others cells do (muscles). But regardless, energy can be produced with or without oxygen. The only important difference is that cells that have no oxygen will produce lactic acid during the glucose metabolism process. And lactic acid--especially in muscle cells--can cause aches and soreness.

  Fortunately, muscle cells (the ones that need the most glucose) usually have oxygen in them, unless for example you have just received a sports massage. But drinking lots of water can eliminate any lactic acid build-up experienced, even then.