Carbs – Simple vs Complex, High Glycemic vs Low Glycemic, Good vs Bad

Aside from misinformed and/or dumb people spreading myths about your daily carb intake, I think the main reason carbs confuse people so much is because there are so many different ways to describe and categorize them.

For example…

  • Good vs bad.
  • Healthy vs unhealthy.
  • Slow vs fast.
  • Simple vs complex.
  • High glycemic vs low glycemic.

I guess the potential for confusion is pretty high when you’re trying to keep track of all of these different classifications.

So, to help clear up this confusion once and for all, let’s take a quick look at the various different “types” of carbs and find out the real truth behind them.

Simple Carbs vs Complex Carbs

High carb foods are defined as simple or complex based on their chemical structure.

The “simpler” that structure is, the faster your body will digest and absorb that food (think sugar, candy, soda, etc.).

The more “complex” that structure is, the slower the digestion and absorption process will be (think vegetables, beans, grains, etc.).

And this digestion/absorption rate stuff is important because, the faster this process takes place within your body, the more it spikes your blood insulin levels.

For this reason, diets high in simple carbs have been shown to increase our risk of diabetes and heart disease, while diets high in complex carbs have actually been shown to help do the opposite.

Simple carbs also tend to be highly processed junk that lacks any nutritional value of any kind, while complex carbs are typically unprocessed, high in fiber, and high in various other important nutrients, vitamins and minerals.

And overall health and nutrition aside, simple carbs are also less filling, which means you’ll be hungrier sooner after eating them. Not to mention, that large spike in blood sugar will result in a crash soon after, and that crash signals hunger and food cravings.

So, as you can clearly see here for many obvious reasons:

  • Simple carbs should typically be greatly limited/avoided.
  • Complex carbs should comprise the majority of your daily carb intake.


There’s just one tiny problem with all of the above. The classification of “simple” and “complex” doesn’t tell the whole story.

It turns out that certain foods that technically fit the “complex carb” label can actually end up causing a rapid spike in blood sugar levels. Similarly, there are some foods fitting the “simple carb” label that really don’t have much of an effect on blood sugar at all.

Confusing, right? Well, to un-confuse this whole carb situation, a little something called the Glycemic Index was created.

The Glycemic Index: High GI vs Low GI

The glycemic index classifies carbs based on how quickly and how high they raise blood sugar levels when compared to pure glucose (sugar), although white bread is now used as the reference food in its place.

And despite the fact that the glycemic index was originally created for diabetics as a way of figuring out which foods would be best for them, it quickly became used by bodybuilders, athletes, and regular people who just want to look good and be healthy.

Why? Because the glycemic index allows us to maintain steady blood glucose levels throughout the day by choosing the right types of high carb foods.

This of course is useful for many reasons, the most important of which are controlling hunger, maintaining energy levels, improving the way our bodies look/perform and preventing a variety of health/medical issues associated with frequent and sustained spikes in blood sugar levels (like type 2 diabetes and heart disease).

How exactly? Quite simply:

A carbohydrate with a high glycemic index (high GI) breaks down quickly during digestion and therefore releases glucose into the bloodstream rapidly. Some common foods with a high GI rating include white bread, white rice, corn flakes, crackers and most sugary and/or highly processed snack foods.

A carbohydrate with a low glycemic index (low GI) breaks down more slowly therefore causing a much slower and more gradual release of glucose into the bloodstream. Some common foods with a low GI rating include most fruits, vegetables, and beans.

What this all loosely translates into in plain English is:

  • High glycemic foods typically = bad for a variety of reasons.
  • Low glycemic foods typically = good for a variety of reasons.


Of course, even though the glycemic index is much more useful than the basic “simple vs complex” classification for figuring out which high carb foods are best for us, it still has its flaws.

For example, the glycemic index does not take normal serving sizes into account.

Meaning, 25 grams of a high glycemic food doesn’t create the same blood sugar spike that 50 grams of that same food would. For this reason, a measure called Glycemic Load was created to account for the amount of carbs present in a serving of a food and help counter this flaw.

Even still, another big issue the glycemic index has is that it only measures foods when eaten in isolation. You know, like if you sat down for a meal that contained nothing but white bread or nothing but corn flakes.

The problem here is that people just aren’t always eating these high carb foods in isolation, and that changes things dramatically. For example, there’s usually something on that bread (turkey, cheese, chicken, etc.), and milk with those corn flakes.

As it turns out, protein, fat and various other nutrients contained in the other foods being eaten at the same time can greatly affect the true glycemic index of a high carb food and the overall digestion/absorption of the meal that food is a part of.

Still, despite not being perfect, the glycemic index is a useful tool for helping us to figure out which high carb foods, in general, are best (and healthiest) for us.

For most of the people, most of the time, low (or possibly moderate) glycemic foods should be your carb of choice. High glycemic foods should be limited to some degree.

Also worth noting now is that if there is one true exception to the above recommendation, it’s your post workout meal (the meal immediately following your workout).

While complex/low glycemic foods should comprise the majority of your carb intake, your post workout meal is the one time of the day when simple/high glycemic foods may actually be the better choice. (More about that later.)

How Do I Find The Glycemic Index or Glycemic Load Of A Food?

As far as I’m aware, this is probably the best resource available:

Does The “Type” Of Carbs Matter For Losing Fat or Building Muscle?

There are actually 2 answers to this question. The first is “nope, not really“ and the second is “yes it does.”

Let me explain…

See, a lot of people (usually of the crazy/obsessed variety) like to think that the answer here is a huge definite yes.

As in, let’s say you cloned yourself and there were now 2 identical versions of you. Both of you worked out the same way and ate the same number of calories each day as well as the same amount of protein and fat (all from identical sources, too).

Now let’s say the only difference between the 2 diets was that one of you ate mostly low glycemic foods, and the other ate mostly high glycemic foods.

A lot of carb-obsessed people like to think that the version of you who ate the so called “bad carbs” would end up gaining more fat and/or building less muscle than the version of you who ate mostly “good carbs.”

Truth is, research shows that with all else being equal, there is little to no DIRECT significant difference in terms of fat gained/lost or muscle gained/lost.

Now, this is definitely NOT me saying that “bad” carbs are good and should be eaten all the time. I’m NOT saying that at all and do NOT recommend that you do.

What I am saying though is that, in terms of body composition with all else being equal, there is no need to kill yourself with guilt or obsess like a crazy person if you enjoy eating white potatoes or white bread or some other similar food not typically considered a “good” carb every once in a while.

Hell, I eat a white potato on an almost daily basis.

Truth is, as long as the rest of your diet is what it’s supposed to be (most importantly your total daily calorie intake), the type of carbs you eat won’t magically cause you to gain fat. Nor will it cause you to magically lose muscle or just build less of it.

Speaking strictly in terms of the direct effect different types of carbs will have on your body’s ability to lose and gain fat, or gain and lose muscle… there is no significant difference whatsoever.

Simple or complex. High glycemic or low glycemic. It just doesn’t matter.


You may have noticed my use of the word “direct” earlier (as in “no direct significant difference”), and that brings us to the “yes it does” portion of my 2 sided answer.

Research does in fact show that there is a significant INDIRECT difference between how different types of carbs affect body composition.

And that is, so called “bad” carbs digest faster and spike blood insulin levels higher, and as I mentioned before, this means you will A) not stay full for long, B) get hungrier sooner, and C) be hungry more often.

And as various studies prove, all of this almost always leads to eating more than you should be eating.

And that right there is how “bad” carbs indirectly affect body composition in a negative way. They cause you to eat more, and eating more is what will cause your body to change in ways you do not want it to.

Plus, body composition aside… let’s not forget about health in general.

All research shows that there is indeed a very significant difference between different types of carbs in terms of your overall health. Diets high in “bad” carbs have been shown to cause a variety of health/medical issues, while diets high in “good” carbs have been shown to help prevent those very same issues.

Putting All Of This Carb Stuff Together

So, here’s what it all comes down to.

Simple carbs vs complex carbs and high glycemic foods vs low glycemic foods doesn’t appear to make any real direct significant difference in terms of fat gain, fat loss, building muscle, etc. as long as everything else (especially total calorie intake) is what it’s supposed to be.

That’s a fact.

However, it still definitely does play many indirect roles in reaching (and not reaching) those goals, most notably in terms of controlling hunger.

At the same time, the differences are indeed quite significant in terms of overall health, as diets high in processed simple and/or high glycemic carbs have been shown to increase our risk of diabetes and heart disease.

More natural, complex and/or low glycemic carbs have been shown to have a reverse, preventative effect.

So, for all of these reasons, here’s what I recommend:

  • The majority of your daily carb intake should come from lower glycemic, higher fiber, nutrient-rich complex sources.
  • Simple, processed, refined, higher glycemic sources should be greatly limited most of the time, with your post workout meal being the main exception.

How Many Grams Of Carbs Per Day and Which Foods To Eat?

With all of that covered, it’s time to move on to the specifics of exactly how many grams of carbs you should eat per day, what foods those carbs should come from, and how to factor it all into your diet plan.

Let’s get to it…

How Many Grams Of Carbs Should I Eat Per Day?

(This article is part of a completely free and amazingly awesome guide to creating the absolute best diet plan possible for your exact goal and preferences. Check out the entire guide here: The Best Diet Plan)