Greetings! In today’s class, we shall discuss sugar.

How The Body Uses Sugar

Sugar is a very important element in nutrition, but its nature and use are little understood by most people. Concerning it there is popular misunderstanding and confusion. The easy way to understand the matter is to begin with sugar as it is found in normal healthy blood, where, for every thousand parts of blood, one part must be sugar – the substance the body cells burn to produce heat and energy for use by all parts of the body. About sixteen ounces of sugar is so used daily in the body of a person weighing 154 pounds doing normal work.

This blood sugar is derived from certain kinds of food. The body can convert a portion of the protein and fat intake into this sugar (glucose), but the larger part of the body’s supply is secured from starch and sugar.

Storage of Sugar

When taken in three meals to provide for 24 hours’ need, the supply is not uniform or steady enough; there is apt to be either a “feast” or a “famine.” Too large amounts would accumulate in the blood at one time unless there were some way to regulate it. For this reason temporary storage is provided in the skin, muscles, and liver. The liver stores sugar in a “compressed” form called “glycogen,” and on demand from the blood it releases it again as glucose for use, as needed. When it is stored in the skin no chemical change takes place in it as it is simply an outflow from the blood stream and an inflow back into it which is called storage by “inundation.” The storage of glucose in the cells is called storage by “segregation” which is more complicated than storage by “inundation.” Storage in the cells and release from them is thought to be under the control of the nervous system in cooperation with glands of internal secretion.

Sugar and the Kidneys

This concentration of sugar in the blood fluctuates from 100 milligrams of sugar in 100 cubic centimeters of blood to 180 milligrams. When it exceeds 180 milligrams the kidneys release the excess into the urine and it is lost from the body. The level at which the kidneys release the sugar is called the “threshold.”

The constant handling of large excesses of sugar by these kidney cells is held by some writers to be one cause of kidney cell damage.

Sugar and the Pancreas

Sugar is rapidly absorbed from the digestive tract into the blood and if large amounts are eaten at a time, so that it enters the blood faster than the body can use or store it, the result will be a “high tide” of sugar in the blood. It is said that in this case the pancreas secretes a larger amount of insulin than it normally does. If this is continued over a considerable period until the cells of the pancreas are depleted, diabetes could result.

Sources of Sugar

The term “sugar” is applied to several types of sweet substances; some of which are excellent foods, while others are irritants to the digestive tract while being prepared to go into the blood stream. It is important that we know the difference between the helpful and harmful types.

Simple Sugar

First we will consider the form of sugar as it is found in normal blood as used in the body. It is known as a “simple” or “single” sugar called a “monosaccharide” because it is the simplest form in which sugar is found, and cannot be further broken down. This is the form in which sugar passes from the small intestine into the blood.

The chemist says every molecule of this sugar is made of 24 atoms, – 6 atoms of carbon, 6 of oxygen, and 12 of hydrogen, associated together. He diagrams a representative molecule as follows; C means carbon, O is for oxygen, and H is for hydrogen:

Glucose, Dextrose, and Grape Sugar (Group 1)

There are three groups of the single sugars, of which this is the first to be discussed. These sugars are used by the cells to produce heat and energy, as already explained; but if they are held too long in the digestive tract they will be attacked by fermentative bacteria, which derive energy for their growth by the partial oxidation of sugar. The chief products of this fermentation are carbon dioxide and alcohol, which will be a curse to the body instead of the blessing as we intended.

These sugars are natural to the body and are proper food for it. They come from the juices of fruits and the saps of plants; even the starch of seeds, roots, bulbs, stems, and leaves, like cereals, potatoes, mature peas and corn, ripe apples and bananas, is broken down by the saliva, pancreatic juice, and the intestinal juice, to glucose – ready for the blood. (This break-down of starch is aided by heat, as in cooking.) During this process of breaking down starch to a single sugar, it passes through two other states, dextrin and maltose.

Fructose (Group 2)

Another single-molecule sugar is fructose, found in fruit, and juices, and honey. This sugar is also natural to the body and proper food for it. However, it is important that nothing hinder the digestive processes, because delay gives time for fermentation of these sugars before they reach the blood.

Galactose (Group 3)

This single sugar is constituent of lactose which occurs in milk, avocados, and sugar beets. This sugar is healthful to us, when it is derived from the avocados and sugar beets.

The Most Common Sugar

The sugar most commonly used is not included in any foregoing groups, and is not natural to the body, and is a very unfavorable food. It is “sucrose”, a double-molecule wherein two single molecules similar to the diagram already given, are linked together; like one molecule of glucose and one of fructose, tied together. (To separate these two molecules, twice the number of water molecules as of the sucrose present are required.) These two single sugar molecules, when separated, are natural to the body; but when linked together, they irritate any tissue they contact. They cannot be separated by the saliva in the mouth, or the gastric juice in the stomach; and while they are finally separated in the small intestine and enter the blood as simple natural sugar, their separation is made after considerable delay, and with difficulty; and until they are separated, they are strong irritants to the cells of mucous membranes of the mouth, stomach, duodenum and small intestine. This irritation often causes serious trouble. Furthermore, this sugar described is the common refined white sugar.

• The natural sugars and starches, as they occur in natural foods, are the most healthful sweets.
• Of the concentrated sweets: honey, maple syrup, agave, and unrefined cane sugar are better options, in moderation.

Grab a friend and share the wealth, from what you’ve learned in the School of Health! In our next class, we shall discuss more about sugar. God bless!

Previous Lessons: Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7