The Difference Between Fiber, Starch and Sugar Carbs
We often think sugar must taste sweet, but most of the sugar we eat is not sweet at all. Sugar is carbohydrate — all carbohydrates are made from sugar. The carbohydrates in the foods we eat come in three different types:
- Simple sugars
- And fiber
These are all made from the same building blocks: sugar. Thus, when we are talking about carbohydrates, we are talking about sugar.
Wherever there is life, you will find carbohydrates. Plants are made from carbohydrates, and all animals use them for energy. Carbs are a miracle. They store the energy from the Sun in a little molecule for us to use later.
When you burn wood in your fireplace, the heat and light is the release of energy that the tree got from the Sun. All carbohydrates come from the same source – plants. You may think that the structure of plants comes from the soil, but the plant doesn’t even need soil, it all comes out of the air and water. The plant takes carbon dioxide (CO2) out of the air and water (H2O) from the ground and makes it into carbohydrate (CH2O) and oxygen (O2). This conversion takes a lot of energy, which is supplied by the Sun. The chemistry looks like this.
CO2 + H2O = CH2O + O2
This is how plants make the oxygen we breathe as they are making carbohydrates for them to use. “Carbo” refers to the carbon atom, and “hydrate” refers to water (H2O). The way they use carbohydrates is amazing! They take each one of these CH2O molecules and string them together to form “polymers,” or strings, of the same molecules. When there are six of them strung together it makes a sugar such as glucose and fructose.
If you count them you will find that each of these sugar molecules has six carbon atoms ©, six oxygen atoms (O), and twelve hydrogen atoms (H). So, it can be written as 6(CH2O). The picture above is simple to see that they are carbo-hydrates, but the structure of sugars forms a ring, instead of a straight line.
These are the primary building blocks of all plants, and the primary energy source of plants, bacteria, archaea, and animals. These molecules have a lot of energy, manifested by burning them. If you are roasting a marshmallow in the fire and you leave it in too long, it will start on fire – that is the energy being released from these sugar molecules, which came from the “Sun” (fire).
The plants can take these and make more polymers, stringing them together to form starches. Starch is just a long chain of connected sugar molecules.
Even the fiber part of plants is made from sugar. Wood is cellulose, which is a chain of glucose molecules, but we can’t digest it because we don’t have the enzymes needed to break the chain.
So, your campfire is burning sugar… your marshmallow that caught on fire is burning sugar…the starch in bread burns sugar when you leave it in the toaster… and when you eat what is left, you can “burn” the sugar for energy.
Cotton fiber is a string of sugar molecules as well. Your blue jeans are made of sugar (cotton), as is that “synthetic” rayon shirt. The money that you bought the clothes with is made of sugar. It’s all sugar!
Long chains of sugar molecules that we cannot use for energy are called “fiber” simply because we aren’t able to digest it, or break the chains. Thus, fiber goes through our digestive tract without getting broken down and ends up in the colon, where bacteria can use some of them. What to us is just fiber might be a feast for bacteria, especially the good kind. “Good” bacteria feed on the things we don’t use, while “bad” bacteria feed on the same stuff we do – simple sugars and starches.
There are many types of chains of sugar molecules that we don’t digest that feed our good bacteria, called prebiotics, not to be confused with PRObiotics, which are the good bacteria themselves. Prebiotics are found in fruit, vegetables, beans, nuts, and whole grains. When food is processed, the fiber is generally removed. Ironically, many people eat food that has the fiber removed, and then add spoonfuls of fiber, like psyllium seeds, orange pulp, or chicory root, to their diet. The best way to get fiber in your diet is to simply eat whole foods.
There are three major classes of prebiotics that are being studied:
Each of these classes of carbohydrate fiber are used by different bacteria. If we take only one type, we can get “dysbiosis” or overgrowth of one type of bacteria. Since it is most healthy for the colon to have many types of bacteria, we need to eat many types of fiber, or prebiotics. Variation in the diet is essential, and thus, your food should be your primary source of prebiotics. The following are a few examples of how to get these wonderful carbohydrates.
|Food||Grams of fiber per serving|
You can see that legumes (beans, peas) are a great source of fiber. Avocado is also excellent. Fiber, or prebiotics, are the kinds of carbohydrates that you should not limit. In eating high-fiber foods you build a healthy gut, immune system, brain and body. You can eat as much of this as you want – and everyone should get more than they currently eat.
A chain of glucose that we can digest for energy is starch. From the moment we put starch into our mouth, such as when we eat bread or a potato, the amylase enzyme in our saliva starts making the starch into sugar. We were told in school that if we put a cracker in our mouth and leave it there, then it will become sweet. I tried it, and I didn’t taste anything sweet. But, despite not tasting glucose, the starch from the cracker is being broken down as we chew as it “turns into” sugar. The following are a list of relative amounts of starch from foods.