subject: What is the Truth About Polysaccharides? [print this page] What is the Truth About Polysaccharides? What is the Truth About Polysaccharides?
When we think about carbs we often think about pasta, bread, potatoes and other starchy vegetables. We think of them when we're told to not eat carbs in our diet, or when we are told to eat more of them. Grains are another major source of carbs, but when you begin to look at carbs from a chemical point of view, we quickly realize that they are but one kind. All carbs break down to three different molecules, and are made up of how they are combined. Starchy grains and vegetables are a kind of carbohydrate called polysaccharides, and these are but one of three. What distinguishes polysaccharides from the other carbs, and how are they similar?
First let's take a look at what the word carbohydrate' means. Basically, that indicates that all carbs are composed of oxygen, hydrogen and carbon. When you combine those atoms into molecules, you get either glucose, fructose, or galactose. Combining those molecules together even further gives rise to sucrose, maltose, and lactose, and once you get beyond ten molecules bound together you get into the polysaccharides.
Polysaccharides are basically incredibly long chains of glucose, some even numbering in the thousands. They can be found in dietary starches, which are then broken down in the digestive system till eventually they are converted via the liver into plain old glucose. This digestion begins in our mouths as a substance called alpha-amylase begins the digestion early. That's why if you chew on bread for a while it will begin to become sweet.
Of interest is that glucose will often be stored in the liver or muscles as glycogen until needed; glycogen is in effect a form of polysaccharides, as they are long chains of glucose just like the starch molecules we are talking about.
Once you understand that starch in vegetables is basically a form of sugar, it makes sense that vegetables, grains and so forth are lumped into the same family group as sucrose and fructose. They are simply the larger assembly line version of those sweets, and as such when consumed in large amounts can result in huge amounts of glucose being dumped into our body. That is why an over consumption of bread, pasta and rice can result in our becoming fat, as our insulin levels push all this excess glucose into our fat cells, since only so much can be stored as glycogen in our muscles and liver.
