Does Soluble Fiber Spike Blood Sugar?

Nope.

But, in some cases, yes.

Read on, because this has been a puzzle for me until recently.

Years ago, best-selling author and leading keto voice, Maria Emmerich called out ChocZero very publicly for having dirty “keto” products that spike blood sugar.

The ingredient she determined to be the culprit in ChocZero’s Maple Syrup was specifically soluble fiber, and she recommends avoiding it completely.

Which is sad, because real, quality soluble fiber should not spike blood sugar. But, even I didn’t know that when I started.

I discovered Maria’s position on soluble fiber awkwardly in 2022 at Keto-Con (now Hack Your Health) Expo when people would stop at my booth, read the ingredients on our gummies, scowl, and put them down without buying or even giving them a try.

As a food maker, this made me very self-conscious. I mean, my ingredients are AWESOME for keto. I’m keto, I should know. This was my first keto conference as a vendor, and these were MY people. So, what was it about my label that they didn’t like?

After several encounters like this, I finally mustered up the courage to ask.

“What is it about my gummies that you don’t like and won’t even try them?”

“Soluble fiber spikes blood sugar. It’s a dirty keto ingredient.” Was the response.

“That’s not true. It’s a true fiber that absolutely does not spike blood sugar.” I replied.

“Not according to Maria Emmerich. Your product has the same ingredient as ChocZero, and it spikes blood sugar. I trust Maria and I don’t eat it.” And they would walk away.

“B-b-but, my products don’t spike blood sugar. They don’t.” I would mumble as they moved on to the next booth.

But, of course I was still a newbie in the ingredient space and had so much more to learn.

This haunted me. Other leaders in the keto space walked by my booth without giving us a second glance.

Of course, I’ve long since won them all over, because, in 4 years, our products do not spike blood sugar. But, ChocZero products do.

Throughout this journey as a food maker, I’ve been obsessed with ingredients. So, when I encounter products “like mine” that use similar ingredients, but spike blood sugar, the nerdy ingredient scientist in me wants to know why.

Soluble fiber is a fiber. I’ve read the studies personally, and I test every ingredient myself before allowing it into my products. And, the soluble fibers we’ve used absolutely do not spike blood sugar. In fact, they even help reduce blood sugar. So, what gives?

I am so invested in the proof of this ingredient based on our personal experience, and the experience of thousands of loyal customers who track their blood sugar. Even Dr. Boz expects all of her patients to test their blood sugar and ketones, and she LOVES our products because they don’t impact this delicate metabolic state.

So, why does ChocZero spike blood sugar, and we don’t?

Is it their natural flavors? Maybe. Natural flavors can contain sugars and maltodextrin (which is why ours are custom formulated for us).

Is it their sweeteners? Maybe. It depends on whether it’s pure or has carriers like maltodextrin. I have no way of knowing.

But, based on my own experience, I was sure it couldn’t be the soluble fiber.

Though, I’ll admit that every now and then I’ve seen comments from people in various keto spaces saying soluble fiber spikes their blood sugar too. Not ours, just in general.

This has baffled me over the past few years, and had me thinking it must be another ingredient in that food that was the culprit because soluble fiber doesn’t spike blood sugar, right?!

I also wondered if maybe it was one of those ingredients that acts differently on different people, and maybe it actually does spike blood sugar in some people.

But, all of our products are Ketogenic Certified—not Keto Certified (a different certifying body that only looks at ingredient labels).

Our products are Ketogenic Certified by a 3rd Party Lab where every product is tested on a number of real people of all kinds, and zero blood sugar spikes.

In 4 years, and thousands of diabetic customer reviews (T1 and T2D), with many strictly keto customers, we haven’t had a single report of a blood sugar spike with our products. Of course, I still recommend testing for yourself, because we all have different metabolisms.

So, what is the difference between our products and ChocZero’s? Because, yes, I’ve tested many of their products, and they are definitely not keto for me.

Well, I think I finally figured it out about a month ago. And, from what I can tell, Maria Emmerich was right after all.

Wait! You just said soluble fiber doesn’t spike blood sugar. Now you’re saying it does?

Ahhhhh, the plot thickens.

In April, we got contacted by an ingredient manufacturer who makes soluble fiber. They’re a big company, respected in the ingredient industry as legit. And, they wanted us to buy their soluble fiber instead of the one we use now. This is normal for us.

Ingredient makers and distributors are constantly trying to get us to try their version of whatever ingredients we use because they know that we don’t let our co-manufacturing partners choose ingredients for us.

They have to be vetted by us, and if when we choose one, it’s a specific brand, with an exact item ID that we provide for each manufacturing partner to use in our products. Because we are so specific, many of the brands that are usually the go-to in our industry, we don’t use.

Anyway, back to the soluble fiber.

We pay more for all of our ingredients because of they way we formulate products and the ingredients we use. So, sometimes, we’ll accept an invitation to explore a less expensive ingredient if we trust the source, and the process of elimination begins.

The ingredient is vetted against our Standards at every stage.

Well, the soluble fiber arrived, and we read through the COA (Certificate of Analysis) and their specs. THIS was the moment I realized how easy it is for a food maker to get duped and end up lying to their customers.

Soluble fiber should not spike blood sugar. There’s so much science on this.

Welp, there’s an exception and it’s such BS.

This soluble fiber contained sugar. 8g of it. That’s 2 TEASPOONS!!

What in the actual what?!?!

This would absolutely spike blood sugar, and I’m willing to bet that many keto food makers use this soluble fiber in their products and have no idea it has sugar in it.

Turns out that the very same ingredient on a label can vary wildly from product to product.

If you’re wondering if they added the sugar to the soluble fiber, probably not. My guess is they have a process which just doesn’t result in a truly pure product. This would result in the presence of residual corn syrup (for soluble corn fiber) or tapioca syrup (for soluble tapioca fiber) in the finished ingredient.

THIS is exactly why I personally vet every ingredient.

Putting “Keto” on a food package is a promise. If it interrupts the keto process, it’s not keto.

We require an exhausting amount of documentation on every ingredient we explore, and if there’s any question, we will have the product 3rd party lab tested, and of course, I wear a CGM (continues glucose monitor) and test my glucose while doing ingredient R&D.

Maria Emmerich was right. Soluble fiber can absolutely spike blood sugar.

I had no idea. But, it’s true.

It really just comes down to the quality of the ingredient itself. Where it’s sourced, how pure it is, whether the manufacturers standards are high or shoddy. Now we know.

We’ll gladly keep paying for premium ingredients we know and trust. Lesson learned.

So, how can you tell if the soluble fiber in a product is pure or if it will spike your blood sugar?

Great question.

The best advice I can give on this is to test it for yourself.

I follow a ketovore diet for the most part. But, I do like to have some treats now and then, condiments for recipes, various snacks and select packaged foods.

I’ve learned the hard way that some of these packaged items completely sabotage me. So, I switched to a safe solution that has helped keep me on track.

Simply put, if I’m trying new food ingredients or a packaged “keto” food, I test.

Sometimes I wear a CGM to track my blood sugar over a month to understand what these ingredients do to my body.

Other times I use a blood ketone and glucose monitor (KetoMojo is my fav).

I will check my blood sugar and ketones when I haven’t eaten anything for some hours, then eat the thing I’m checking, and test again a couple of hours after.

I’ve found It’s the only way to truly know for myself.

I hope you feel more empowered when switching to foods that serve your health journey instead of sabotaging it. Soluble fiber is a functional ingredient that can help the metabolism, I even wrote a whole post on it here.

But, that’s only true if it’s a pure soluble fiber that does not spike your blood sugar.

Bravo, Maria Emmerich! Thank you for raising the alarm. This was a great mystery to unravel.