It seems like there is something always in the news about carbohydrates and is something we hear about constantly in American culture. Let’s take a look and how of carbohydrates work and why you should care about them. There are simple carbohydrates and complex carbohydrates, where complex carbohydrates are supposed to be better for your health than the simple ones. There are so many diets with recommendations of eating low carb like the Atkins, Banting, or the Dukan diet. These diets are supposed to help you lose lots of weight by somehow eliminating the bad effects of carbohydrates. Then there’s the more esoteric subjects like the glycemic index. This has to do with how fast or slow a carbohydrate goes from your gastrointestinal system to the blood stream.
You’ve probably heard about glucose and fructose, these are the simplest of the carbohydrates. They are molecules containing six carbon atoms, 6 oxygen atoms and 12 hydrogen atoms. The word carbohydrate actually comes from “carbo” and relates to the number of carbon molecules. The term “hydrate” is simply to add water, or hydrogen and oxygen. It’s the number of carbon atoms that have oxygen and hydrogen atoms. Plants make carbohydrates from sunlight and many animals eat the plants and some animals eat those animals and plants. Glucose, or pure fructose being the simplest of the carbohydrates, can be immediately absorbed by the small intestine into the bloodstream (assuming everything is healthy). Table sugar or sucrose, is a disaccharide composed of one glucose and one fructose molecule are bonded together. An enzyme in your small intestine can break the bond holding the glucose and fructose together, and then they can be immediately absorbed in your small intestine and then they enter the bloodstream. Bigger carbohydrates like starches, are found in wheat, vegetables or rice to name just a few. These larger complex carbohydrates are composed of a longer chain of glucose molecules connected together your body has enzymes that can break it apart.
White bread has a very high glycemic index because the flour that the white bread is made from is so highly processed. Whole grains, beans, nuts and vegetables contain carbohydrates, but these carbohydrates take much longer to break down in the small intestine. The glucose from these foods enters the bloodstream much more slowly and thus have a low glycemic index. It is said that this is healthier because they don’t cause such an intense spike in blood insulin. Blunting these insulin spikes is often the goal of many lower carb ways of eating. Keep in mind what a typical American diet looks like. Things like a bowl of cereal, a slice of pizza, a can of ravioli, a bottle of soda, potato chips, packages of cookies, bowls of ice cream are common foods in the typical American diet. These foods often contain something like 40 to 50 grams of carbohydrates per serving, therefore a typical American eating a typical American diet can easily consume 300 plus grams of carbs per day or more without even thinking about it. A lunch consisting of two slices of pizza, a chocolate chip cookie and a big soda is easily 200 grams of carbs. Even more, it all comes in into the bloodstream in just a few minutes. And this surge of glucose pumping into the bloodstream requires your body to use a lot of insulin to handle the glucose spike. And many spikes like this over the years can cause pre diabetes or metabolic syndrome, where your body becomes resistant to the effects of the insulin that your pancreas is putting into the bloodstream. Diabetes and obesity eventually results from the increased calories and metabolic syndrome which has its own set of health effects. Carbohydrate restriction, say 50 grams of carbs per day rather than 300, can decrease the spikes in blood insulin, which lowers hunger pangs and reduces the number of calories you consume per day. A common question arises whether or not a low carb diet can hurt you. Some nutritionists bring up the scenario that a lower carb diet will cause metabolic derangements resulting in ketosis and acidosis and osteoporosis and other diseases will arise from restricting carbohydrates long term. But the truth of the matter is that if you go to a hospital, you will see that people are dying of metabolic syndrome and diabetes. There is not a ward full of osteoporosis patients. Diabetes is so prevalent, that no matter how you cut it, if you want to cut medical costs and save lives, we have to make a dent in the diabetes.
Another example that you may know of is that your brain and nervous system require glucose. If you do not take in carbohydrates, will your brain die? It’s just not the case; when necessary, the body can manufacture its own carbohydrates via your liver and kidneys through a process called gluconeogenesis. This process is important, and there are many examples where gluconeogenesis occurs in life. Let’s say you’re lost in the desert and had no food for 5 days, or you’re fasting for a prolonged period of time, or you get sick and can’t eat for a few days, or if you’re living in an extremely cold climate and meat is your only source of food, in all of these cases there’s no glucose coming in so your body uses gluconeogenesis to make glucose. And to make it even more complex, the body can use fat metabolism as energy and it does quite well with it. But we’ll tackle that subject next time since this post is about carbohydrates.
This whole thing is really fascinating and that carbohydrates are just one source of food energy, but there are several more and there are all these different aspects to it and it is truly amazing how carb consumption can have a huge impact on your overall health. The more you learn about carbohydrates, the more interesting it becomes.