On a chemical level, carbohydrates are comprised of carbon, oxygen, and hydrogen. Carbohydrates occur in chain-like formations, with shorter chains called Monosaccharides and Disaccharides, while longer chains are called Polysaccharides.
Of course, to the average consumer, a course in chemistry isn’t exactly the aim of an education in carbohydrates. Most consumers simply want to know what carbohydrates are, why we need them, and, more importantly, how to recognize the difference between “good” and “bad” carbohydrates.
Interestingly, the categorization of “good” and “bad” carbohydrates is a relatively recent phenomenon, one that has arisen with the development of the obesity epidemic. A mere fifty or sixty years ago, the delineation between good and bad carbohydrates was simply related to whether or not the kids should eat candy before dinnertime.
Today, when we talk about good and bad carbohydrates, we’re primarily speaking about the effect of different types of carbohydrate on blood sugar.
When we consume carbohydrate-rich foods or beverages, there is a natural rise in blood sugar as carbohydrate is broken down into simple sugar molecules. Ideally, blood sugar should remain fairly steady. The body has a complex system to regulate blood sugar. An excess of sugar in the bloodstream is dangerous (a condition known as hyperglycaemia), as is too little blood sugar (a condition known as hypoglycaemia). The body counteracts these highs and lows with a storage system and the help of a hormone called insulin.
Good carbohydrates are those that elicit a long, steady rise in blood sugar, while bad carbohydrates are those that cause blood sugar to rise and fall in a dramatic fashion. Consistent consumption of bad carbohydrates ultimately creates a metabolic system that transitions very rapidly from high to low, setting the stage for cellular inflammation, Type II diabetes, and metabolic disease.
So good and bad carbohydrates don’t have anything to do with weight?
Not exactly. While many consumers hold the mistaken belief that good and bad carbohydrates are categorized according to weight-friendliness, this isn’t always the case.
Total caloric intake serves as the ultimate determinant of weight outcome, regardless of the healthfulness of dietary intake. In other words? If you consume too many calories, you’ll gain weight, regardless of whether you’re consuming “healthy” or “unhealthy” foods.
While many good carbohydrates are also low in calories, others contain the same number of calories as simple, refined (bad) carbohydrates.
For example, whole wheat bread (a good carbohydrate) and white bread (a bad carbohydrate”) contain the same number of calories. Whole wheat bread is considered to be a good carbohydrate because it contains the whole grain- the bran, germ, and endosperm are all intact. This increases the fiber content of the finished product. High-fiber foods tend to stabilize blood sugar because they take longer to digest, eliciting a longer, steadier rise in blood sugar.
Refined grains (bad carbohydrates, like white bread) have had the bran and germ removed, leaving only the endosperm in the finished product. The lower fiber content of refined grains elicits a faster rise in blood sugar, because the bran and germ contain the majority of the fiber.
How can I tell the difference between a good and bad carbohydrate?
Good carbohydrates tend to be: high in fiber, bear “100% whole wheat” or “100% whole grain” on the ingredient list, and be low in added sugars. Foods like whole fruits and vegetables, whole wheat bread, brown rice, and whole wheat pasta are all healthy carbohydrates.
Bad carbohydrates tend to: contain a flour or grain-based ingredient that does not bear the “100% whole” label before its name, contain added sugars, and be low in fiber. Foods like fruit juice, sugar-sweetened beverages, sugar, desserts, white bread, pasta, and white rice are all bad carbohydrates.