Simple vs Complex Carbohydrates: The Difference Explained

Are you on the Carbohydrate Train?

The question of whether carbs are good or bad is one I get most often- and it’s no wonder why.⠀

Between the latest diet trends, influencer comments and one-sided nutritional advice, it’s easy to see why most would be confused.⠀

Personally, I’ve never been a fan of labels… and that is especially true when it comes to calling something ‘good’ or ‘bad’.⠀

I believe that our language is extremely powerful- and by referring to something as bad, we are creating a belief in our minds that can cause more damage than good.⠀

Carbohydrates aren’t ‘bad’. In fact, they are our body’s main energy source that helps to fuel our brain, heart, kidneys, nervous system and more!

That being said, there certainly is a choice you can make for fueling your body with the BEST carbohydrates- meaning making the active choice to select ‘complex’ carbohydrates instead of opting for ‘simple’ ones.

So what exactly are complex or simple carbohydrates, and how do you tell the difference?

The difference between simple & complex:

Simple carbohydrates are ones that are quickly broken down/digested by the body, and result in a rapid increase of your blood sugar. These are refined- meaning they lack part of their original make up, resulting in a most (if not all) of the nutrients being removed.

Think of things like white rice, most pasta, white bread, or anything that uses white/all purpose flour (pastries, cereal, crackers, wraps, etc.).

These carbohydrate sources often provide no nutritional benefit as they have been ‘stripped’ of all beneficial properties, are usually loaded with other processed ingredients like sugar, and can cause detrimental effects to our bodies over time.

Complex carbohydrates are digested more slowly and supply a lower/more steady release of glucose into the blood stream. For the most part, they are what we call whole grains- ones where the grain is left in ‘whole’ form.

Think of things like brown or wild rice, quinoa, millet, amaranth, corn, oats, barley, legumes, starchy vegetables, etc.⠀

These carbohydrate sources have higher nutritional value- plus they keep your blood sugar levels stabilized, help to increase your overall energy, and keep you feeling full for longer.

So, why is this difference important?

Carbohydrates that digest rapidly, have a high-glycemic index or a high-glycemic load, result in a rapid increase of your blood sugar.

When you have significant and frequent spikes in blood sugar,  abnormal reactions between proteins and carbohydrates can occur throughout the body, resulting in a pro-inflammatory environment.

Persistent high blood sugar levels can result in complications such as diabetes, nerve damage, vision loss, kidney damage or problems, and even cardiovascular disease.

Think of the last time you had a big, heavy meal with simple carbohydrates- perhaps a holiday dinner? You likely ate a big meal, and shortly after experienced a crash (where the blood sugar levels dropped rapidly after spiking), and ended up feeling sleepy and hungry for desserts even though you still felt full.

This is because your body is having a hard time digesting the foods that have been eaten- and this is just one of the ways on how the sudden rise and fall of your blood sugar levels can effect you.

Not to mention, the levels of nutrients between simple and complex carbohydrates can vary drastically! See below for an explanation on what exactly refined means.

Image by Skinny Chef.

What does refined mean?

A grain in its whole form has three parts- the bran (which is the outside layer), the endosperm (which is the middle layer), and the germ (which is the very center of the grain).

The BRAN is a fiber-rich coating that protects the seed, containing B vitamins and trace minerals.

The ENDOSPERM is the middle layer that contains the carbohydrate, along with the protein.

The GERM is the small, nutrient rich center that contains antioxidants, vitamins, minerals and healthy fats.

When you have a grain in it’s whole form (meaning a complex carbohydrate), it contains all three of these components and all of the potential nutrients you would get from eating that grain.

However, when you have a refined grain (meaning a simple carbohydrate), the bran and germ have been removed- leaving only the endosperm as part of that grain.

This results in the majority of the nutrients being removed from that grain, and also explains how the rapid increase in blood sugar that these cause: as these grains no longer have the bran (meaning the protective coating on the outside), our digestive enzymes are able to penetrate them fast, resulting in a rapid digestion and conversion of the carbohydrates to sugar.

Where as with a complex carbohydrate, that protective coating remains intact- slowing down the process of digestion as our digestive enzymes have to work hard to penetrate the grain and release the carbohydrate. This is why our blood sugar remains stable when eating complex carbohydrates or whole grains!

So how do you choose the best carbohydrates?

As we discussed above, there are multiple reasons why choosing complex carbohydrates is best for your health, including receiving the most nutrients AND keeping your blood sugar stable.

But how do you know which grains to choose?

First, it’s important to note whether or not you require gluten-free grains (like I do). If you do, rest assured that there are a LOT of great gluten-free whole grains out there, which are noted in the list below.

The other important thing to note, is that we are all built uniquely different- so which carbohydrates work the best for your body and the amount of them you eat is up to you. I recommend experimenting with different types and amounts to see what makes you feel your best.

Now, one additional thing to note is that although you can certainly enjoy things like pasta or bread in a healthful way, these are not whole grains. They can USE whole grains in their ingredients- but once a grain has become pulverized it will increase your blood sugar rapidly regardless of whether or not it contains the bran and germ, because the surface area of the endosperm becomes wide spread and is no longer protected by the bran.

In this case, I recommend choosing a pasta that is made from a lentil or bean base (like chickpeas), to prevent or reduce this effect. As for breads, it is a great idea to look for one that contains visible grains either in a whole, cracked or split variety, or to choose a bread that uses an alternate flour (like almond or coconut flour).

The same goes for home baking/cooking- it is a great idea to move away from traditional white or whole wheat flours, and instead work on incorporating other flours or even using rolled oats instead.

Fruits and vegetables are also a fantastic carbohydrate source as they are high in fiber which slows digestion and promotes stable blood sugar levels. They’re also packed with antioxidants which help reduce inflammation in the body. 

Here is a great list of complex carbohydrates to get you started:

  • Amaranth (GF)
  • Barley
  • Brown Rice (GF)
  • Buckwheat/Kasha (GF)
  • Bulgur
  • Butternut Squash (GF)
  • Corn (GF)
  • Couscous
  • Farro
  • Green Peas (GF)
  • Kamut
  • Legumes, such as black beans, chickpeas, lentils, and others. (GF)
  • Millet (GF)
  • Oats (GF- if certified)
  • Potatoes (GF)
  • Quinoa (GF)
  • Rye
  • Sorghum (GF)
  • Spelt
  • Sweet Potatoes (GF)
  • Teff- a type of Millet (GF)
  • Wheat
  • Wild Rice


Please note that this list is not extensive and only contains ‘some’ complex carbohydrates to get you started. I recommend starting to incorporate some of these carbohydrates into your dietary regime on a daily basis, and switching them up regularly!

Whenever possible, opt to select complex carbohydrates (especially whole grains) instead of a refined one.

I hope this list helps you, and I’d love to know if you have any additional questions.

You can also checkout my video HERE that I made to explain this subject as well.


Best of luck!


Brianne xx

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Hi, I’m Brianne

Here at The Holistic RN you’ll find a place where holistic healing and western medicine come together to create a brand new way of looking at your health- including real food recipes, easy to understand information and overflowing inspiration. Let’s get started!

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