PLANTS WERE MANKIND’S FIRST AND SMARTEST CHOICE TO EAT. Metabolism, in both plants and animals, is the process of breaking down food nutrients to make energy and build up our body’s cells.  Nutrients the plants make and pass onto people are a lot more complex than the materials the plant took in to make them. Therefore, we have developed a much more complex system of organs to metabolize these substances.  This process, from eating the food, through the breaking down of the food so it can enter the blood stream, is called digestion. We humans devour everything the plant has to offer: water, sugar, carbohydrates, proteins, amino acids, fats, minerals, enzymes, vitamins. The food we get from plants is broken down in our digestive system, and makes its way into the body's cells through our blood.  There it is met by the oxygen we obtain through our respiratory system, and is metabolized to make energy and the building blocks of our body tissue.  Waste products, like carbon dioxide, are passed back out the cell through the blood and out of the body. The glucose discussed in the previous chapter can pass directly into our blood stream.  This blood sugar (glucose) is the topic of much study and confusion.  Selling of glucose remedies has become highly commercialized. They are touted as an aide to help combat such ailments as diabetes, high blood pressure, and low blood sugar. With all the hype, it would be nice to know a few important facts about sugar.  For instance: exactly what is sugar, how much is in different plants, how much does our body need and how much is too much?   Sugar categories:                                                              Sugars, Sucrose, Glucose (dextrose), Fructose, Lactose, Maltose, Galactose.     Here is a neophyte exposure to the following sugar categories to help you understand their function: Sugars, Sucrose, Glucose (sometimes called dextrose), Fructose.        Sugar is a carbohydrate First of all, sugar is technically classified as a carbohydrate because it has the elements carbon, hydrogen, and oxygen.  More precisely, sugars are classified as simple carbohydrates.  Yes, there are simple carbohydrates and complex carbohydrates.  The difference is that the elements in complex carbohydrates are bonded in a configuration that won’t readily break down into substances that can be absorbed by the blood as sugars.  Complex carbohydrates are broken down by enzymes and digestive juices into sugars to be absorbed into the bloodstream.  The sugars listed above are the simplest substances that the blood can absorb, with glucose being the easiest, followed by fructose, sucrose, and then the other sugars. Complex carbohydrates are at the back of the line. Glucose is blood sugar, and blood sugar is glucose.  Because it is readily soluble in liquid, it is absorbed into the blood.