Video | Testing Dark Chocolates | 72% Cacao | 86% Cacao | 92% Cacao | 100% Cacao | Sugar Substitute Sweetened Chocolate | Results

I ate chocolate for breakfast for the past four days to see how different levels of cacao and different sweeteners used in dark chocolate would affect my blood sugar. 

Dark chocolate has health value. But at what level of dark does that value start, and at what point do the added ingredients tip the scale from healthy to unhealthy? 

That’s a big question, and while we might not be able to answer it fully, this blog post chips away a big chunk by looking at blood sugar impact. Join me to see what my continuous glucose monitor (CGM) showed as the best and worst dark chocolate. 

Blood Sugar vs. Dark Chocolate: I Ran the Tests. Which Chocolate is Best? [Video]

In this video, you’ll learn…

• The methods and materials I used to test the dark chocolates.
• How each dark chocolate affected blood sugar levels.
• Which dark chocolate is the best choice.

Testing Dark Chocolates

Why did I eat the chocolate for breakfast? Because these tests are focused on blood sugar. If I had them after dinner, the foods from my meal would combine with the chocolate, so we wouldn’t know if the change in my blood sugar level was due to the food or the chocolate. 

I ate the chocolates at 7 o’clock in the morning on an empty stomach. I used 200-calorie portions as a standard for comparison. While I did not exercise during the 2-hour testing period, I did drink black coffee (because there were only so many sacrifices I was willing to make).

In a previous blog post, I tested 72% cacao chocolate. That percentage is just high enough to earn “healthy chocolate” status, and the results were so-so, which I will recap for you in a moment. 

For this round of testing, I wanted to see if increasing the cacao amounts made a difference, so I compared my 72% chocolate results to bars with 86% cacao, 92%, and 100%. I also tested dark chocolate sweetened with sugar substitutes.  

To be deemed a good snack for blood sugar control, the chocolate must perform well in two ways. First, I want to see a minimal blood sugar spike immediately after eating it. Second, I want a stable or gentle blood sugar rise and fall in the two-hour period after consumption.

The intensity of that first spike shows me how the chocolate is affecting me. The degree of the rise and fall over time shows me how my body is handling the snack. 

My Levels app made it easy for me to watch these two things unfold in real-time. If you’d like more information, I go into detail about the Levels app and using a CGM in the video above.

Dark Chocolate Comparisons

Let’s take a look at how the chocolates affected my blood sugar levels. 

In the first dark chocolate test, I chose Ghirardelli 72% cacao chocolates. To limit confounding variables, I decided to stick with Ghirardelli chocolates for my cacao comparisons. 

72% Cacao Dark Chocolate Blood Sugar Test

The biggest drawback with the 72% dark chocolate is that sugar is the second ingredient. 

• 72% Dark Chocolate Ingredients: Unsweetened chocolate, cane sugar, cocoa butter, vanilla extract, soy lecithin

After seeing the response caused by eating it, I concluded that even though this snack contains more than 70% cacao, which allows it to fall into the “healthy chocolate” category, the high sugar content caused an unhealthy blood sugar response. 

Let’s see what happens as we increase the percentage of cacao and move sugar lower on the ingredients list. 

86% Cacao Dark Chocolate Blood Sugar Test

On packaged foods, ingredients are listed by quantity. So, the closer the ingredient is to the beginning of the list, the more the food contains.

When we compare the ingredients list of 72% cacao chocolate to that of the 86% variety, we see that cane sugar and cocoa butter switch places. 

• 72% Dark Chocolate Ingredients: Unsweetened chocolate, cane sugar, cocoa butter, vanilla extract, soy lecithin
• 86% Dark Chocolate Ingredients: Unsweetened chocolate, cocoa butter, cane sugar, milk fat, natural flavor, vanilla extract, soy lecithin

In other words, there is less sugar and more fat in the 86% bar. The 86% bar also has added milk fat.

How much of a blood sugar impact can we expect?

Remember that dietary fat is a macronutrient that causes little or no rise in blood sugar, and carbs cause the highest rise.

Because the 86% dark chocolate contained more fat and less sugar, which is a carbohydrate, I expect less of an initial blood sugar spike and more stability in the two hours after eating it compared to the 72% bar.

And, that is what happened.

The 72% cacao chocolate with sugar listed as its second highest ingredient caused a moderate blood sugar spike, receiving a so-so score of 4 out of 10, whereas the 86% with less sugar and more fat caused a nice gentle rise and received a pretty good score of 7. 

On to the next step up in cacao to see if this trend of higher fat and lower carbs continues to improve my blood sugar response. 

92% Cacao Dark Chocolate Blood Sugar Test

The ingredients in a 92% cacao dark chocolate bar are almost the same as that of the 86%, with the only difference being that “natural flavor” and “vanilla extract” swapped places. 

• 86% Dark Chocolate Ingredients: Unsweetened chocolate, cocoa butter, cane sugar, milk fat, natural flavor, vanilla extract, soy lecithin
• 92% Dark Chocolate Ingredients: Unsweetened chocolate, cocoa butter, cane sugar, milk fat, vanilla extract, natural flavor, soy lecithin

The term “natural flavor” is tricky because it doesn’t tell you anything other than it is flavoring that comes from a natural source. That source can be anything from fruit to eggs, and you’ll likely never learn the original source because it is often a mixture of flavors. 

If you read ingredients, you have seen this vague term on many different foods, and the vagueness is allowed because its primary function in the food is flavoring, not nutrition. 

Does it impact your blood sugar? Well. Again. It’s vague. However, its impact on health or blood sugar is likely dose-dependent, meaning that I would not gobble down a food with “natural flavor” listed as the first ingredient, but if it is lower on the list, as with these dark chocolates, the amount is small enough that it does not raise my concern.

If I see a change in my blood sugar response, it will most likely be due to the fact that the 92% bar had fewer carbs and slightly more fat than the 86%. 

At 7 AM, I ate a 200-calorie portion of 92% cacao chocolate and waited for my Levels app to analyze it for me. It resulted in a stable blood sugar response and received a score of 8 out of 10, which was a good score and slightly better than the 86% that scored a 7 out of 10. 

I next tested 100% cacao dark chocolate. 

100% Cacao Dark Chocolate Blood Sugar Test

Every logical fiber in my being told me that this would be the best chocolate for blood sugar. It has one ingredient: Unsweetened chocolate. It is baker’s chocolate with no sugar and no additives. To be honest, I included it as more or less an experimental control. 

• 100% Dark Chocolate Ingredient: Unsweetened chocolate

The 2-hour blood sugar response was astonishing. It only scored 5 out of 10, causing a moderate spike that was more similar to the high-sugar 72% cacao chocolate than the 92% variety.

Health Factors of 100% Chocolate

It’s important to note that blood sugar response is not the only determining factor for health value. This is the highest level of cacao, meaning it should provide the richest supply of antioxidants and minerals of the chocolates tested. 

Having said that. To me, it tasted horrible. Getting down three squares, which was my standard 200-calorie testing portion was very hard. One square a day likely has health benefits, but personally, I would have to find a way to consume it other than straight off the bar.

The 100% cacao chocolate bar contains more carbohydrate grams than the 86% and 92% varieties. Why? Well, some of it may be a rounding issue, which I will get to in a moment. It may also be due to the fact that this is just the chocolate, which started life as a plant, so it is more purely carb with no added fat like the other bars. 

Calories and Macros Do Not Match

The calories and macros do not match on the 100% cacao food label. It tells us that there are 70 calories in one piece (14g). However, there are 8 grams of fat, 5 grams of carbs, and 2 grams of protein. 

We have been taught that one gram of fat has 9 calories, and a gram of carbs and protein each has 4 calories. If we do the math, we see that there are 100 calories per piece. 

• 8 grams of fat x 9 calories = 72 calories
• 5 grams of carbs x 4 calories = 20 calories
• 2 grams of protein x 4 calories = 8 calories
  • TOTAL CALORIES: 100

According to the food label, there are 70 calories per serving, but according to the macros there are 100 calories. That is quite a difference. What’s going on? 

I will tell you that there is often a small discrepancy between calories and macros, but this was a big one. I will quickly walk through what is usually going on, but I am stumped. 

FDA Nutrition Label Accuracy

First, according to the FDA, “Nutrition labels can be inaccurate by up to 20% when it comes to listing calories.”

Even with that somewhat shocking understanding, we have a 30-calorie difference, which is closer to a 40% difference. The only thing that might close that gap is the fact that the FDA’s inaccuracy allowance is based on the actual laboratory analysis of the food, not the 9,4,4, calorie counting model I just ran through. 

In other words, the simplistic 9,4,4 model is overly simplified. Calories are not this rigid. For instance, we consider each gram of protein to have 4 calories. However, protein is made up of different amino acids. Those amino acids can vary in their calorie content, with some having around 3 calories per gram and others having 6 calories per gram.

The food label will tell you the correct grams of protein, but the calories can vary depending on which amino acids are most prevalent. And similar calorie variations are seen with different types of carbs and fat. 

Also, some adjustments may be made for fiber and sugar alcohols because they are not completely digested. Still, a 30-calorie difference per piece is baffling. Did this play a role in the so-so blood sugar response? Again. I’m not sure. 

Lastly, I wanted to test dark chocolate sweetened with sugar substitutes. 

Sugar Substitute Sweetened Dark Chocolate Blood Sugar Test

There are many on the market. I chose a Skinny Me bar because it was in my local grocery store. Ghirardelli did not have a variety of non-sugar sweetened chocolate. This bar has all of the right wording on the packaging: “Skinny,” “Bold Dark,” “Zero Sugar,” “Gluten Free,” and “Keto Friendly”

The ingredients list lets us know that the sweetness comes from inulin, erythritol, natural flavors, and stevia.

• Sugar-substitutes Chocolate Ingredients: Unsweetened chocolate, inulin, resistant dextrin, erythritol, cocoa butter, milk fat, organic soy lecithin, natural flavors, stevia extract, vanilla extract

What you don’t know is the level of cacao. Just saying “Bold Dark” on the package does not mean it is over that 70% cacao threshold where we see the high-antioxidant health benefits.

A 200-calorie portion has a fair amount of fat, with 17.8 grams, which is in the ballpark of the other chocolates. However, this bar contains a lot more carbohydrates and fiber than the others. 

How did a dark chocolate bar sweetened with sugar substitutes impact my blood sugar? 

It received a Levels score of 7 out of 10. 

That is not bad for blood sugar. I cannot tell from this test if the suppressed blood sugar response was a result of the non-sugar sweeteners or the added fiber. That would be something to explore in a follow-up test. 

Is this a good solution for controlling blood sugar and still getting to enjoy chocolate? I would not give this a rave review for health because of one question that remains. Is the cacao amount in this bar high enough to make this chocolate healthy? We don’t know since the label only says, “Bold Dark,” which kind of leaves us in the dark. 

Results: Blood Sugar vs. Dark Chocolate

There we have it. From the Level’s scores, we see that 92% cacao chocolate provides the best blood sugar stability, followed by the bar sweetened with sugar substitutes, the 86% bar, the 100% cacao bar, and coming in at last place is the 72% chocolate. 

From our tests, I am declaring 92% cacao the winner because it created a stable blood sugar response, has a good level of cacao, and just a touch of sweetness, so it didn’t stimulate my appetite.

Thank you for reading and have a wonderful week!

About the Author

Becky Gillaspy, DC, is the author of The Intermittent Fasting Guide and Cookbook. She graduated Summa Cum Laude with research honors from Palmer College of Chiropractic in 1991.