Human Petroleum (page 1 of 2)

Carbohydrates, however, are a key part of healthy nutrition. Like any other food, there are "good" and "bad" carbohydrates.

Like protein, carbohydrates are molecules used by the body for various functions. They contain carbon, hydrogen, and oxygen. Unlike protein, carbohydrates do not contain any nitrogen. The popular way to group carbohydrates used to be simple sugars (sucrose, fructose, glucose, etc) and complex carbohydrates (any carbohydrate composed of multiple sugar molecules bonded together). The belief was that simple carbohydrates are bad, while complex carbohydrates are good.

This belief has turned out to be false. All carbohydrates, whether simple sugars or complex starches, are broken down by the digestive system and absorbed into the bloodstream as simple sugars. Regardless of whether the carbohydrate you eat comes from table sugar or a bowl of salad, most of it ends up as glucose in the bloodstream. Fiber is the exception, because it is a type of carbohydrate that the body is not able to breakdown, and therefore it passes through the digestive system without providing calories to the body.

The glycemic index (GI) changed the way carbohydrates are classified. The index has been around for decades, but only recently have nutritionists began to consider the GI of carbohydrates when deciding what is good or bad. The glycemic index measures how quickly blood sugar levels rise after eating a specific quantity of food. This index uncovered that complex carbohydrates like maltodextrin (used to sweeten many foods and shakes) and potato are digested very rapidly and cause extreme rises in blood sugar levels, with some simple carbohydrates such as fructose and agate nectar are digested more slowly. Therefore, many simple carbohydrates are better choices than complex carbohydrates!

There are many reasons why carbohydrates are digested at different rates. The presence of proteins, fats, and fibers in a meal can slow overall digestion. Certain fruits such as bananas convert starches to sugars as they ripen. Fresh bananas will have less of an impact on blood sugar than ripe bananas. Enzymes in the body also readily break down certain types of starches - for example, the starches in potatoes are broken down to simple sugars in the mouth even before they pass into the gut. Most heavily processed foods are also broken down, stripped of fiber and other nutrients and are therefore easier for the body to quickly digest.

Many diets have been formed around the concept of the glycemic index. Low GI foods are digested more slowly and impact blood sugar less severely. These foods are ideal for diabetics who must regulate their blood sugar levels. Many studies suggest that low GI diets may actually result in greater fat loss compared to other diets with the same amount of calories that are composed of higher GI foods. The glycemic index, however, does not paint the full picture.

Carrots are high on the glycemic index. Consuming carrots, however, does not cause blood sugar to rise significantly or quickly. The reason is that while the carbohydrates in carrots are quickly ingested by the body, there are only a few grams of these carbohydrates in a typical serving. In other words, it would require a large quantity of carrots to get enough carbohydrate in order to have a detrimental impact on blood sugar.

To address this discrepancy, the glycemic load (GL) was introduced. Glycemic load refers to the amount of carbohydrate in a standard serving of food. Food with heavy starches like potatoes have a high GL, while foods loaded with fiber, nutrients, and water like carrots have a relatively low GL.

The gylcemic index is rated on a scale from 0 to 100, where 100 is the rate at which pure glucose enters the bloodstream.