Overview of carbohydrates.
Carbohydrates provide the most easily accessible energy source for your body. The other main sources of energy are protein and fats. However, carbohydrates are efficiently converted into glucose which will be used for energy. Glucose is used directly by your muscles and brain. Excess glucose is stored as glycogen in your muscles. Where a supply of glucose is not available, your muscles will burn fat as a source of energy.
By being converted into glucose, levels of carbohydrates will affect your blood sugar levels. Your blood sugar levels are important because your brain uses glucose from your blood. This explains why people often get depressed and down beat whilst on diets. Your blood sugar levels are not something that should be neglected!
Carbohydrates come in two forms: Simple carbohydrates and complex carbohydrates. Simple carbohydrates contain naturally occurring sugars, such as those found in fruit (fructose) for example. The sugars that make up simple carbohydrates also include table sugar (sucrose) and a variety of syrups.
Because simple carbohydrates are already simple sugars they can rapidly be converted into glucose and enter the bloodstream very soon after consumption. This where the term "sugar fix" comes from. After drinking a sugary cup of tea, for example, you may notice a sudden release of energy and an accompanying lift in your mood. However, have too much and your body will produce insulin to counteract the effect and, depending on how much sugar you've ingested, this will likely result in a rapid drop in blood sugar level and leave you feeling more tired than before!
So what are complex carbohydrates then? Complex carbohydrates are present in most grain products, vegetables and potatoes. Unlike simple carbohydrates, complex carbs are digested at a much slower rate. As a result of this, the conversion to glucose also happens at a slower rate and your blood sugar levels will not fluctuate as rapidly as they do when digesting simple carbohydrates.
Many people will try and avoid all types of carbohydrates where possible, particularly when on weight loss diets. This is not a good idea. Carbohydrates in general are not normally a problem. It's the quality of carbohydrates that should be taken into account. Highly processed foods should be avoided. This is because they normally contain a higher proportion of simple carbohydrates. For example, whole grain bread (complex carbs) should be eaten instead of white bread which uses refined white flour (simple carbs).
Complex carbohydrates are often also lower in fat and provide higher amounts of other essential nutrients like dietary fiber. It is for the above reasons that a diet of complex carbohydrates is preferable.