Carbs: A Super-Simple Guide

Photo © Sharon Mollerus

If you poke around on the internet for the word carbohydrates, you’ll find a vast array of articles and websites all centered around one of two words: “good” or “bad.” Recommendation after recommendation, each more controversial than the last.

What you’ll be hard pressed to find is an actual definition. (Wikipedia’s is good if not overly comprehensive, rendering it difficult to both interpret and, more importantly, apply.)

So let's break it down. Nothing controversial or overly-scientific: just some simple facts and thoughts.

What Are Carbs And How Are They Used?

To put it plainly (and pointedly for our purposes), carbohydrates—AKA “carbs”—are chains of sugars that are found in many of the foods that we eat. These chains vary in length, so you'll sometimes hear the terms “simple” and “complex” used when referring to them. The distinction between the two, though, seems to be not well defined, so it’s probably more accurate to think of them as more or less complex (ditto simple) as compared to others.

Carbs are used by the body for energy production. When you eat carb-containing foods, they are broken down into their constituent parts (sugars) and released into the bloodstream. The more simple the carbohydrate, the more quickly this happens. With this increase in blood sugar levels, the pancreas releases the hormone insulin to direct the sugar to where it needs to go.

There are three main fates for the sugars. They can be:

  1. Used immediately for energy (remember, every cell in the body needs a continuous supply of energy);
  2. Stored in the muscles or liver as glycogen (a storage form of sugar in the body);
  3. Transformed in the liver into triglycerides (fats) and stored for later use.

Please note that nothing I just laid out is inherently good or bad. Each of the steps above is crucial to our survival. What can get us into trouble is the limited capacity of steps 1 and 2 alongside the limitless capacity of step 3.

How Can Carbs Be Useful?

Most of us have heard the terms aerobic and anaerobic. These refer to the ways in which the body produces energy from its fuels (either with the use of oxygen or without, respectively). The aerobic pathway is for activities of low intensity and can be sustained for long periods of time (like walking); the anaerobic pathway is for short bursts of high intensity (like sprinting or weightlifting).

Carbohydrates shine when you are involved in high-intensity activities. The anaerobic pathway can only be fueled by glucose (either in the form of blood sugar or glycogen), so the more active you are, the more carbohydrates you’re likely to need. This will vary based on the person and the activity level, but the guiding principle should be to earn your carbs.

How Can Carbs Be Harmful?

Carbs can be harmful when we over-eat them (especially the highly processed, rapidly absorbing kind). Our bodies work very hard to keep blood sugar levels within a very tight range: not too high and not too low. The more quickly carbohydrates are digested and released into the bloodstream, the larger the spike in blood sugar that then has to be cleared.

How is this harmful? The issue is essentially two-fold.

First, as mentioned above, the ability of the body to either use blood sugar immediately for energy or store it as glycogen is limited. Any excess that can’t be used right away in one of these two ways must be stored for later use (in our fat cells) since it can’t be allowed to hang around in the bloodstream for long.

Second, blood sugar must come with a corresponding amount of insulin for anything to happen with it. Chronically elevated insulin levels can lead to a condition known as insulin resistance. What this essentially means is that the tissues in the body no longer respond to insulin as well as they used to, so the pancreas has to release even more insulin to clear the same amount of blood sugar. Not only does this put an added load on the pancreas, but it’s a vicious cycle that can lead to a whole host of other issues, including Type II Diabetes, obesity, heart disease…the list goes on.

To Sum Up

As you can see, carbs can be both good and bad. They can be helpful, harmful, or totally benign. The deciding factor? You guessed it: Context! Figure out where you are in terms of activity level (be honest!), and use that to help determine how many carbs you might actually need in a day. And this doesn’t have to be a rigid, hard-and-fast number. Just keep it in a nice range.

For a really simple tool to get you started, check out Mark Sisson’s Carbohydrate Curve.

Until next time!