What is Sugar?

Sugar is a carbohydrate. Sugar is a source of energy in the body and is a structural component of the cells.

For example, d-ribose, a form of sugar is a building block of adenosine triphosphate (ATP), a nucleotide produced by the body for energy release.

Most people recognize sugar as a white crystalline substance used as a sweetener in food and drink.

However sugar is a 'loose term' and refers to a collection of different types of carbohydrates - not just white refined sugar so prevalent in the western diet.

There are two main categories of sugar: simple and complex.

Simple Sugars

Simple sugars are a basic form of carbohydrate. 'Simple' refers to the sugar molecules structural formation.

Simple sugars belong to one of two categories: monosaccharides and disaccharides. Saccharides are a group of carbohydrates which include starches and sugars.

Examples of monosaccharides include:

  • ribose
  • glucose
  • fructose
  • galactose

Sources of simple sugars include:

  • fruit
  • milk
  • hop - a plant and ingredient in beer

Complex Sugars (Complex Carbohydrates)

By contrast and by name, complex sugars are more 'complex' in their structure compared to simple sugars.

Complex sugars contain three or more units of sugar.

As sugar is a carbohydrate, complex sugars are often referred to as complex carbohydrates, although this term encompasses other items including starches.

The are two types of complex carbohydrates: assimilable polysaccharides and non-assimilable polysaccharides.

Assimilable Polysaccharides

If a complex carbohydrate is assimilable it can be readily absorbed by the body and incorporated into body tissue. Examples of assimilable complex carbohydrates include starch and amylose.

Sources of Complex Carbohydrates (Assimilable Polysaccharies) include:

  • potatoes
  • pasta
  • rice

Non-assimilable Polysaccharides

These complex carbohydrates are not readily absorbed by the body. Examples of non-assimilable polysaccharides include cellulose, gums and pectins.

Sources of Complex Carbohydrates (Non-Assimilable Polysaccharies) include:

  • seeds
  • pulses
  • green vegetables

Simple & Complex Sugar Sugars & The Glycemic Index

The glycemic index is a measure of scale which ranks the effect a carbohydrate has on raising blood sugar levels after eating.

In general, simple sugars have higher glycemic index (GI) values giving a more rapid rise in blood sugar levels. Complex carbohydrates tend to have lower GI values and raise blood sugar to a lower level.