The Different Types of Sugar

Sugar is the generic name for sweet-tasting, soluble carbohydrates. These are divided into monosaccharides and (compound) disaccharides.

Monosaccharides (simple sugars)

• Glucose

• Fructose

• Galactose

• Xylose

Disaccharides (compound sugars)

• Sucrose (50% glucose and 50% fructose)
  Table sugar is commonly extracted from sugar cane or sugar beets

• Lactose (glucose + galactose)

• Maltose (two molecules of glucose)

In the body, compound sugars are hydrolyzed/broken down into simple sugars.

Glucose

Also known as dextrose or grape sugar, it occurs naturally in fruits and plant juices and is the primary product of photosynthesis. Most ingested carbohydrates are converted into glucose during digestion and can be used by cells directly as a primary source of energy for living organisms.

Fructose

Occurs naturally in fruits, some root vegetables (sugar beets), sugar cane sugar, agave, honey, and is the sweetest of the sugars. It is one of the components of sucrose/table sugar. It is also manufactured from hydrolyzed corn starch that has been processed to yield corn syrup, with enzymes then added to convert part of the glucose into fructose.

Galactose

It does not occur in the free state but is a constituent with glucose of the disaccharide lactose or milk sugar. It is less sweet than glucose. About as sweet as glucose, and about 65% as sweet as sucrose. Galactose is a component of the antigens present on blood cells that determine blood type within the ABO blood group system.

Xylose

A sugar first isolated from wood, also found in straw, is classified as a monosaccharide of the aldopentose type. It is derived from hemicellulose, one of the main constituents of biomass. It is absorbed but primarily excreted by the kidneys.

Sucrose, glucose, and fructose are three types of sugar that contain the same number of calories gram for gram. (4/gram)

Since monosaccharides are already in their simplest form, they don’t need to be broken down before your body can use them. They’re absorbed directly into your bloodstream, primarily in your small intestine.

On the other hand, disaccharides like sucrose must be broken down into simple sugars before they can be absorbed.

Health

Fructose has been linked to several adverse health effects such as obesity, type 2 diabetes, insulin resistance, and fatty liver disease.

Sugars found in foods, such as fruits, vegetables, and dairy products don’t seem to result in any ill effects. The nutrients, fiber, and water may counter any of their negative effects. Eaten as added sugar in our diet is associated with significant ill effects. The average American consumes 82 grams of added sugars per day. The World Health Organization (WHO) recommends limiting added sugars to 5–10% of daily calorie consumption. (i.e. 25-50 grams on a 2,000 calories/day diet)