Nutritionists and health reporters often say that we need so-called complex carbohydrates in our diets, that these are the “good carbs”, and are important to our health. (Sugars are “simple carbohydrates” and therefore often referred to as “bad carbs”.) Unfortunately, many of the claims made in the media contain many distortions and conflicting information about complex carbohydrates and the foods which contain them. This means that I get a lot of questions about what they are and how much to eat.
What Are Complex Carbohydrates?
Traditionally, the term “complex carbohydrate” is a more user-friendly version of the word “polysaccharide” (the “sac” means “sugar” and “poly” is many). Long strings of simple sugars mostly form either starch or fiber, which are make up the majority of complex carbohydrates. However, traditionally, fiber has been separated out into its own category, and the term “complex carbohydrate” mainly referred to starch. This makes sense, because starch and fiber behave very differently in the body. Starch is used for energy when it is broken down into sugar molecules, whereas fiber “passes through” – the body cannot use the glucose molecules in it for energy.
More Detailed Information About Types of Carbohydrates:
More recently, writers of popular health information have used the term “complex carbohydrates” to refer to foods which have a lot of starch and/or fiber. Since foods high in starch and those high in fiber are not always the same, it’s caused some confusion. Worse, some writers have started to refer to some foods as “complex carbs”, instead of the term referring to a component of foods. It has led to the unfortunate situation of spinach (high in fiber and nutrients, but hardly any digestible carbohydrate) and corn flakes (high in starch that has been pummeled into a super-digestible form, but little fiber) both being called “complex carbs”.
These are the top bogus assertions I see about complex carbohydrates:
Myth #1: Complex Carbohydrates are Digested Slowly
This claim is usually made when comparing complex carbs (starches) to simple carbohydrates (sugars). The claim is that complex carbohydrates are less glycemic (raise blood sugar less or more slowly). Of course, fiber is not digested at all, but starchy foods are often VERY rapidly digested, with those starches being broken down into sugars lickety-split. Quickly-absorbed complex carbohydrates include potatoes and most other root vegetables, refined (white) grains, any processed starch (breakfast cereals, corn chips, most snack foods), and any grains which are ground into flour, including whole grain flour and baked goods made with it. There are exceptions: the carbohydrate in legumes, particularly when cooked at home (not canned), and left intact instead of mashed, tends to be digested more slowly. Also, whole, intact grains (not pulverized, ground into flour, etc.) are, on average, digested more slowly than processed grains. However, there is a lot of variability in how rapidly people digest them. (This is one of the problems with the glycemic index. Don’t get me started).
Myth #2: Complex Carbohydrates Contain Important Vitamins (and other nutrients)
This one drives me crazy, and is an illustration of the problem I talked about before. First of all, in this usage when they say complex carbohydrates, they mean “foods high in fiber and/or starch” (carbohydrate itself has no vitamins; it’s just sugars). Some of these (e.g. broccoli) are very high in nutrients per calorie, and others (e.g. corn) are much less so. Furthermore, plenty of foods that have no carbohydrate, complex or otherwise — beef, for instance — are as or more nutrient-dense as many of the starchy foods.
Myth #3 Fruit as a Complex Carbohydrate
All I can say is: NOT! The digestible carbohydrate in almost all fruit is sugar (simple carbohydrate), and most fruit does not have much fiber, particularly when compared to the amount of sugar. The exceptions: the low-sugar fruits (mostly berries) tend to have relatively larger amounts of fiber. It is really stretching any definition of “complex carbohydrate” to the breaking point to include fruit, and yet I see this mistake again and again. Low-Carb Fruit List
Myth #4: Complex Carbohydrates are Vital to Our Health
The usual line here is that carbohydrates are vital for energy, and that we would collapse in exhaustion without this energy source. Apparently the word that fats can be used for energy has not gotten out. Especially for people losing weight, the whole idea is to use fat for energy – primarily the fat we’ve been carrying around with us. Granted, it takes a week or two for the body to “get off the sugar” and shift to using primarily fats for energy, but once that happens many people report enjoying sustained energy throughout the day, without the previous intermittent crashes.
For people following a low-carb way of eating, it’s important to “make our carbs count” by mostly choosing carb sources that are high in nutrients, such as non-starchy vegetables, nuts, and low-sugar fruits (like berries). If we are doing that, whether or not the carbohydrates are “simple” or “complex” becomes irrelevant.