Sugar is the name applied to a popular class of foods that are sweet-flavored carbohydrates composed of oxygen, hydrogen, and carbon. There are a variety of different sugars derived from different sources, all of which share the same unique characteristic of sweetness to human taste buds. People like the taste of sweet foods, hence their popularity and growth in the foods that make up our modern diet.
There are two basic types of sugars, the monosaccharides, which are the simplest carbohydrates, usually water-soluble, crystalline, and colorless solids; and the disaccharides, which are carbohydrates formed when two monosaccharides condense together. The monosaccharide sugars include glucose, galactose, and fructose.
Sucrose is probably the most popular form of sugar and is composed of 50% fructose and 50% glucose. Sucrose is common granular table sugar, and it is in the disaccharide group of carbohydrates, which also include two others: lactose, and maltose.
Lactose is a disaccharide sugar found mostly in milk and is formed from glucose and galactose. It was discovered in 1619 by Fabriccio Bartoletti and identified in 1780 as a sugar by Carl Wilhelm Scheele. By weight, lactose makes up around 2-8% of milk composition, although it varies among individuals and species.
Maltose- This sugar is known as maltobiose, or malt sugar, and is a disaccharide formed from a condensation reaction. It has a milder sweet taste, about one-sixth as sweet as fructose and half as sweet as glucose. Maltose is a common ingredient in confectionery in China and Taiwan. It is often consumed as a spread sandwiched between two crackers. Maltose is also produced when glucose is caramelized and also found in germinating seeds, such as barley, as they break down starch to use for food.
Sugar is found in most plant tissue; however, it is particularly concentrated for efficient commercial extraction in sugar beet and sugarcane plants. Sugarcane is a giant grass plant that has been cultivated since ancient times in the Far East and tropical climates. In the 18th century, sugar became a popular spice among the aristocracy and later it was made available to the common masses, as well. Large sugar plantations were established in the West Indies and the Americas to supply the growing demand. Prior to that time, people mostly used honey to sweeten their bread, cake, pastries, coffee and fruit drinks. Sugar beet, by contrast, is a root crop that was cultivated in cooler climates, and became a major source of commercial sugar later on in the 19th century as efficient sugar extraction processes became available.
As its popularity grew, sugar production blossomed into a major world-wide industry and changed the course of human events in many ways. Sugar trade stimulated settlement in the American colonies, expansion of slavery, indentured labor, migrations of various ethnic groups, development of major shipping routes, and indirectly, the wars between sugar controlling nations and the new world producers.
Fructose, which is a simple sugar found in fruit and vegetables, has become a good source for energy in the human body. It does not cause significant blood glucose spikes like some of the others, and it was once thought that it would be a good substitute for table sugar. The American Diabetes Association, however, changed their opinion on this because fructose is processed in the liver. When too much fructose enters the liver, and it can’t be processed, the liver converts it to fats and sends it off into the bloodstream as triglycerides (blood fat). This can be very dangerous for several reasons:
- High blood triglycerides can lead to heart disease and stroke.
- Digestion of fructose circumvents the normal appetite signaling system, which prevents the release of hormones that regulate appetite, thus leaving a person unsatisfied and wanting more. Consequently, excess consumption of fructose is associated with weight gain.
- Excess consumption of fructose may also lead to insulin resistance and type 2 diabetes.
High Fructose Corn Syrup (HFCS) – This food additive is not a sugar, but a major source for it in many foods. It has become the single largest source of calories in the American diet. It is so prevalent, it is in almost every food on supermarket shelves these days; just read the labels. It is composed of 55% fructose and 45% glucose, so gram-for-gram, it doesn’t have much more fructose than table sugar. The problem, however, is that it has become incredibly abundant and inexpensive, partially due to U.S. corn subsidies. Since it is such a cheap sweetener, it has crept into so many foods in our diet, that it is now causing serious health issues like those mentioned above. The human body was simply not meant to process so much sugar.
Xylose – This sugar was first isolated from wood and is named for it; the Greek word xylos means wood. Xylose comprises about 30% of plant matter and is the main building block for hemicelluloses, and it is found in the embryos of most edible plants.
Glucose – This sugar, also known as grape sugar and dextrose, is a simple carbohydrate found in plants, and one of the three dietary monosaccharides that are absorbed directly into the bloodstream as digestion occurs. This simple sugar is one of the main products of photosynthesis and is the fuel used in cellular respiration. Glucose is the key source of energy in the human body, through aerobic respiration, and provides about 3.75 kilocalories of food energy per gram. Most carbohydrates broken down in the body form glucose, and from bacteria to humans, it is used as a main energy source in most organisms. The human brain uses glucose as the primary source of energy, and when it is low, psychological processes and decision-making become impaired.
Honey- This is a natural sweet food made by bees from the nectar of flowers. It is not a sugar, but derives its sweetness from the two monosaccharides, fructose and glucose. It has about the same composition as HFCS, 55% fructose and 45% glucose, and tastes as sweet as granulated table sugar. Some people actually prefer its taste over that of sucrose and use it instead. It is used in baking and most microorganisms will not grow in honey due to its low water activity.
Galactose is another sugar found primarily in milk and milk products, but also in sugar beets, and other gums and mucilages. It is synthesized by the human body, and forms part of glycolipids and glycoproteins in several different tissues. Galactose metabolism converts galactose into glucose. Conversely, glucose can be changed into galactose via hexoneogenesis, which enable the mammary glands to secrete lactose. Most lactose found in breast milk, however, is synthesized from galactose from the blood, and only 36% is made from galactose from de novo synthesis.
All this sugar is not healthy for human consumption and is responsible for many of the declining health conditions in our society today. The diet of our early ancestors had very little sugar in it. As if this constant barrage of sugar isn’t enough to compromise most diets and overwork the pancreas, the availability of simple carbohydrates exacerbates the problem. Starch often has as much effect on blood glucose levels as sugar itself, so it is smart for consumers to look for the total carbohydrates rather than only total sugars on food labels. As a result, the majority of Americans have become obese, with an alarming portion of the teenage population becoming morbidly obese because they eat from vending machines and fast food restaurants. Put in simplest terms, our food is killing us.
Many consumers have tried to eat less sugar in their diets, but the labels don’t always disclose the actual contents used in the products, so it is not simply a matter of weak will-power and bad choices, so much as it is the non-disclosure of the ingredients. Food processors purposely try to make consumers think certain foods are good for glucose control when, in fact, they aren’t at all. Foods that are labeled “Low Calorie” and “No Sugar Added” may still be loaded with high starch content that will send blood glucose levels skyrocketing. The proliferation of sugar and starch throughout our food are not the only culprits, but they are certainly significant players, and their long-term effects will have devastating consequences on our national health care if we don’t educate our population on how to eat a proper diet. The real problem is the poison tastes so darn good.