In Defense of Carbs

This is an exciting topic – with all diets from keto to vegan carbs are a popular piece of contention. Most people, whether they are “pro-carb” or not, tend to cringe when they hear this starchy word because of all the hype around it these days. Before we get into the debate, let’s learn about how this macronutrient works on a biochemical level.

Carbohydrates are one of the quickest forms of fuel for your body. When your mouth waters as you eat, you are actually releasing enzymes that will begin the digestion of carbohydrates once you place them in your mouth - before you even chew and swallow them! Because carbs break down so quickly, they are also able to be absorbed and used for energy rapidly. This is exactly why they make such a great fuel before a workout.

At a micro level, all carbs are made up of glucose- a form of sugar which is the simplest form of carbohydrate. They attach to one another to form chains and in more complex carbs, they grow to form branches. When digestion of these carbohydrates occurs, glucose molecules are stripped from the chains and branches to produce single glucose molecules. This is the sugar that enters your bloodstream through your gut in a process called absorption.

Once glucose molecules are in your bloodstream, they travel to fuel-needy cells so that they can be transformed into energy. Glucose is a large and complex molecule that can’t enter your cells unless you have insulin (and well-functioning insulin signals) to let the glucose in. Insulin is a very important hormone for this reason, but insulin also produces other reactions in the body as well. Insulin is an anabolic hormone which means it tells the body to build itself up. This may not be a bad thing when you are trying to build muscle, but if you do not know how to consume protein to maximize its absorption, or if you aren’t exercising to stimulate muscle-protein synthesis, then you may be building more fat than you want with carbs! This is often why carbs get such a bad rep. It’s not that carbs are a bad thing to eat, it’s that many people consume them at the wrong time and with disproportionate amounts of other macronutrients.

The one exception to this rule is a type of carb you may know as fiber, which is much less digestible than other carbs. The great thing about fiber is that it stays mostly in tact from the time that it enters your body to the time that it leaves, meaning very little of it can be converted into fat. The little bit of fiber that is digested in your gut is not actually digested by you, but by the colonies of bacteria that live within your intestines, otherwise known as microbiota. This microbiome produces a wide array of health benefits for you including the synthesis of vitamin K and a number of essential B vitamins as well.

If you are interested in experimenting with your carb intake, there are 3 important things to consider: timing, quantity and pairing. Carbs typically take around 15 minutes – 2 hours to digest, depending on their complexity. So if you want to gauge your energy levels with a simple carb, such as low-fiber fruit, try doing this less than an hour before your workout, allowing time for digestion to take place. Also keep in mind that consuming large amounts of carbs before a workout will delay digestion, this is simply because there is more to digest. Finally, when consuming carbs prior to a workout, avoid high-fat foods, and excessive protein and fiber as they are not as easily digested and can cause stomach upset. 

Jenna Moore, RD

Michele Bergh