Nutrition > The Difference Between Complex & Simple Carbohydrates
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The Difference Between Complex & Simple Carbohydrates

3rd Oct 19

Carbohydrates are a huge macronutrient that is involved in pretty much anything. They’re often talked about as both good and bad in your diet, but knowing what’s what and what you actually need are vital steps in your journey to a balanced diet. Plus, it gives you the best chance to reach your fitness goals. Typically, the argument begins with the difference between simple and complex carbohydrates.

Let’s take a look:

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What Are Carbohydrates?

Carbohydrates are, simply put, sugars. They come in different forms, but that’s the bottom line. Don’t panic; not all sugars are harmful. Carbohydrates actually have a lot to offer you in your diet, and you need both simple and complex carbs in some form or another to run efficiently in the long term.

What Do They Do?

A combination of simple and complex carbohydrates is what gives you the fuel you need to keep you ticking over, or most of it at least. The biggest difference between them, most of the time, is how they act. This goes for how they are consumed, too, of course.

It all comes down to how the body reacts to them and turns them into useable resources that we need to keep us going.

Types of Carbohydrates

Simple Carbohydrates

Let’s start with simple carbs. These are the smaller chains of the two. What does that mean? They’re easier to deal with because they’re less complex (or more simplistic). They come from things like fruit and sugars, as well as pretty much anything else sweet. The human body is able to break down these things rapidly, and that’s where some of the issues lie. (This applies to both natural and refined sugars too).

Firstly, they cause a spike in blood sugar. That means that you get a little hyperactive a lot of the time. After that, the fall in blood sugar. That’s where we feel a bit of a crash. Worse still, we get hungry again. This is one of the easiest ways to lead yourself to overeat and getting even more of these simple carbs to satisfy your craving, causing the cycle to repeat.

Complex Carbohydrates

Complex carbs, as you have likely guessed, are the opposite of simple carbs. They typically come from healthier foods like whole grains in bread, rice and pasta, rather than the simple sugars in sweets, sugar and fruit. They’re also referred to as a much healthier sounding compound that is starch.

Because of their more complex chemical structure, they take a lot longer to break down and absorb. They make us feel fuller for longer, and the energy is released gradually rather than in huge waves. They can even be found in a lot of less sweet fruits and vegetables too, which only adds to the nutritional content. It’s not all about grains and wheat.

Refined Carbohydrates

Before you walk away knowing the difference, there’s one other aspect to the simple vs complex carbohydrates battle, and that’s refined carbs. They’re a bit of a wild card, but they’re still worth knowing about. This is where a lot of the commonly seen ‘bad carbs’ come from.

Refined carbs a kind of the middle ground. They tend to be found in things like white bread and pastries, which are not the worst things in our diets and aren’t full of sugar but are still not exactly always great for our health. It’s not as black and white as you might think.


So, now we know what the difference is, but when is best to use both simple and complex carbs to their full potential? Both have their uses after all (as well as usually tasting great). You need to play them to their strengths after all.

The best way to do it is to fuel up on complex carbs a few hours before you need them. That’s where a lot of your stamina is coming from in the long game, or if you’re going to be exercising for a while. It makes sense.

Simple carbs are awesome as a mid-workout snack though, or even just before you do it. Say you wake up at 7 am and are hitting the gym before work, for example. A banana full of simple carbs on your way there may give you that burst of energy to get you through before the more complex carbs could have even got you started. Don’t underestimate the power of either.

Ultimately, they both have their place, although complex carbs often have a lot more nutritional value to them. Simple carbs are still needed though, especially in fruits and vegetables. That’s where tonnes of vitamins and minerals come from after all. Use both in a healthy balanced diet alongside when you’ll be training and take it easier on carbs on your rest days for proper calorie management. Healthy fats and protein help you to recover and rebuild anyway.

For a little more info on carbs, check out this link from

Before beginning any exercise or nutrition program, consult your physician, doctor or other professional. This is especially important for individuals over the age of 35 or persons with pre-existing health problems. assumes no responsibility for personal injury or property damage sustained using our advice.

If you experience dizziness, nausea, chest pain, or any other abnormal symptoms, stop the workout at once and consult a physician or doctor immediately.