Carbohydrate, Obesity and Weight Loss
Carbohydrate refers to organic molecules that contain only
carbon hydrogen and oxygen atoms and moreover the ratio of of hydrogen to
oxygen atoms is two-to-one (the same as water{H2O}) making the basic
chemical formula for carbohydrate the following: C(H2O). In this sense, carbohydrate appears to be "hydrated (watered) carbon"--hence
the name.
Polysaccharides
"polysaccharides" are chains longer than ten sugars and are
familiar to most people as simply "starch".
Carbohydrate Digestion
The human small intestine can only absorb simple sugars like glucose.
Every other kind of carbohydrate from table sugar to potato starch must
first be digested by enzymes that eventually break the carbohydrate down
entirely into simple sugars.
Carbohydrate Metabolism
Carbohydrate metabolism, like nearly all metabolism, is extremely
complex and far beyond the scope of this website. Still, several points should
be stressed.
-Carbohydrate is the only macronutrient that is not essential for human life.
In the total absence of dietary carbohydrate, the body produces ketone
bodies to keep the brain alive and manages to actually make glucose from
certain amino acids and from glycerol that is liberated from
triglycerides. This process of glucose synthesis is called
"gluconeogenesis" and is discussed elsewhere.
-Carbohydrate that circulates in the blood is always in the form of a monosaccharide and by far the most prevalent of these monosaccharides is glucose or "blood sugar".
-Increasing levels of blood glucose trigger the pancreas in healthy people to secrete
the hormone "insulin" which causes muscle and other tissue to absorb glucose
from the blood and therebye maintain glucose levels within a limited range.
-The disease of "diabetes mellitus" is named for the fact that it
causes people to have sweet tasting urine (this truly was an ancient way
of diagnosing the disease and the sweet flavor is due to the presence of
large amounts of glucose in the urine caused by extremely high blood
glucose levels.
-Diabetes mellitus is the name given to two totally different diseases that happen
to both share the feature of very high blood glucose levels.
-Type-1 diabetes is also called "childhood-onset" diabetes, tends to
strike children and young adults, tends to develop extremely rapidly(often
within weeks) and is usually very serious and hard to control from the
outset. Nearly all patients with type 1 diabetes are insulin dependant.
Type-1 diabetes is caused by a failure of the pancreas to produce insulin
due to the sudden death of all or nearly all of its insulin-producing
cells. Most scientists believe that type 1 diabetes is caused by a virus
although the causitive agent is not certain.
-Type-2 diabetes is also called "adult-onset" diabetes and tends to
develop in adults. Type-2 diabetes usually develops slowly and worsen
slowly over years. Type-2 diabetes is caused not by a lack of insulin production
from the pancreas, but rather by insulin resistance. Among the strongest
risk factors for type-2 diabetes are obesity, metabolic syndrome, family
history and early indications of insulin resistance like rising
glyco-hemoglobin (HbA1C) levels. Type-2 diabetes presents in varying
degrees of severity: some people can control it just by reducing sugar and
carbohydrate in their meals, many patients achieve good control through
the use of one or a combination of several oral medications while some
type-2 diabetics require insulin injection.