Simply put a carbohydrate is a molecule that can be broken down by your body and used for feed your cells. Carbs, proteins, and lipids (fat) can all be used by your body to fuel your body though out the day. Of the three of these, carbohydrates are by far the most easily broken down. They require less energy and fewer steps than proteins or fats to be broken down into basic units of sugar (glucose) and used to fuel your cells. At the end of the day your cells run on this simple sugar. Glucose is gobbled up by the cells, broken down into a few smaller molecules called ATP, which is then used to aid the cell in doing whatever it does. Muscle cells contract, nerve cells fire and impulses are conducted, and so on.
So why, if the body runs most efficiently on glucose, and carbs are the best source for it, is there such an uproar about eating them? Can’t I just have a coke for breakfast, lunch, and dinner and get on with it?
In a word, nope. Why? Several reasons.
First off we need to understand there are two types of carbohydrates, simple and complex.
Simple carbs are usually present in what are called “processed” foods. The grain or complex sugar or whatever the food is made of has already undergone processing outside the body, in the manufacturing stage. Twinkies, white bread, sugar, fruit juices, white flour, sodas, etc. are all made of ingredients which have already been broken down into sugar. Some foods are naturally more filled with simple carbs such as potatoes and other starchy vegetables.
Complex carbohydrates are present in more “whole” foods. That is, foods which are made from ingredients which have undergone a minimum of processing before they are consumed. Whole grains such as whole wheat, oats, and brown rice, pasta, legumes and green leafy vegetables are all considered to be complex carbs. The body takes longer to digest these sugars, and releases the processed material into the body more slowly. These foods are also important for all the other nutrients they contain.
But why, if it’s all going to be turned into glucose anyway, does it matter if we eat simple or complex carbohydrates?
The answer is a matter of timing and distribution. Yes, at the basic cellular level our body uses glucose to do all the fancy things it does all day long. But it is not equipped to handle having too much of this basic unit flooding into it all at once. The job of your digestive system is to break down complex substances and turn them into basic chemical units that your body then absorbs. This should take time. Your body is supposed to do the processing. It’s made for it. When we eat too many simple carbs the digestive process doesn’t need to do its job of breaking down substances gradually and sending the resulting glucose out to the cells. The sugars are already simple and the body is flooded with glucose that it can’t use all of immediately. It then turns the unused portion into fat and stores it for later use. And that’s where the bad rap comes from. AAAHHH, my sugars are turning into fat!!! How will I fit into my new Lululemon capris if I have more fat?!!!
Alternatively, when we eat some complex carbs, preferably with some protein (which is broken down into amino acids and recycled back into protein for, among other things, building your muscles), and some fat (which slows digestion and contributes to all sorts of essential functions in the body), we give the digestive system a chance to gradually distribute these substances into the blood stream. This gives us more sustained energy without the dreaded “sugar crash” of its simple carb counterpart. It also helps prevent burdening the pancreas with so much glucose that it can’t keep up with the demand for insulin, (necessary for metabolizing sugar), making you more vulnerable to developing Type II Diabetes.
So yes, you may want to run, run for your life away from carbohydrates, but only if they come as the simple, processed variety. They’re not all criminals.