Let's start with the calories coming from carbohydrates. We will be exploring two basic categories of carbohydrates: simple and complex. Simple carbs consist of a single sugar molecule (monosaccharide) or two single sugar molecules linked together (disaccharide). Complex carbs are formed when thousands of sugar molecules are linked together in long chains (polysaccharides). Some examples of complex carbs are oatmeal, brown rice, and yams. Examples of simple carbs would be table sugar, fruit juice, and corn syrup, and refined/processed carbs such as most breakfast cereals, breads and pastas made from white flour. These two different types of carbs alone have drastically different effects on the body.
Simple carbs are quickly released into the bloodstream, causing a rapid rise in blood sugar. The body responds to this by releasing a large amount of insulin, which removes glucose from the bloodstream and delivers it to cells to be used as energy. This also keeps blood sugar at a safe level. Any excess glucose will be stored in muscles and the liver. Once glycogen stores are full, the rest will be converted and stored as body fat. Simple carbs result in a quick energy burst and a crash that follows, leaving you fatigued and craving for more carbs. Additionally, over time cells become more and more resistant to insulin which results in the pancreas having to secrete more of it to have the same effect. Because insulin has the ability to prevent the body from using stored fat as energy and plays a role in the deposition of body fat, higher insulin levels will result in a rapid accumulation of body fat. Consequently, with continual exposure to higher and higher amounts of insulin, cells can get to a point where they are no longer responsive to it, or the pancreas simply can't secrete enough of it to be effective. This condition is known as diabetes. Other effects of long term over eating of simple carbs are: damage to teeth and gums, inflammation, high blood pressure, and heart disease.
Conversely, complex carbs take longer to break down when consumed, supplying a slow and steady stream of glucose into the bloodstream. This keeps blood sugar levels stable, avoiding spikes in insulin and fluctuations in energy. The likelihood of storing these carbs as body fat is much lower. Additionally these types of carbs will keep you full longer and will allow for a more regular appetite. Complex carbs will generally include a fair amount of fiber which promotes healthy digestion and elimination and acts as an all around internal cleanser.
It should already be clear that not all calories are created equal. However, this brief overview of two different types of carbohydrates is far from the whole story. We have yet to explore the differences in calories that come from proteins and fats. Also, I'll reveal why losing weight from indiscriminate calorie counting may actually leave you with more body fat! Stay tuned for part II.
By Chris Lentino, DO.IRON, NASM CPT, PES personal trainer at Whippany Athletic Club