Is Isomalt Keto Friendly? Yes But Don’t (Use This Keto Sweetener Instead)

Keto (Low Carb) | Written by Nathan | Updated on 23 November 2022

A red translucent flower candy sculpture made out of isomalt keto friendly crystals and is on top of a yellow to white cake that has red speckles of isolmalt on it too.

Is isomalt keto friendly?

Keto dieters are usually very familiar with no calorie sweeteners, but isomalt is lesser known sugar alcohol that’s used in various products and cooking instructions. 

The truth is, yes, isomalt is keto but understanding it’s carb contents will prove that isomalt is really just okay to use on keto and depending on the application, you should use these 5 low carb keto sweeteners seen below instead. 

Is Isomalt Keto Friendly? Is Isomalt Keto Diet Approved to Use Daily?

Isomalt dates all the way back to the 1960’s and is a fairly keto-friendly sugar free sweetener called a sugar alcohol. Sugar alcohols look and feel like sugar, but they are actually derived from different plants and berries through a chemical process and are just a fraction of the calories of normal sugar.1 Isomalt comes from the sugar of beets and while it has many similarities to sugar, including taste, it has only between 50% to 60% of its sweetness. 

The common use of isomalt is as a replacement for sugar in hard candies and works particularly well in types of candy that need to be boiled as well as sugar sculptures due to its propensity not to crystallize. However, it typically needs to be combined with additional sweeteners to enhance its own sweetness.

So, what makes sugar alcohols and isomalt keto friendly for the most part? Most people who are well versed in the keto diet know that to successfully stay in ketosis, the most important factor is keeping daily carbohydrate under 50 grams.2 Sugar alcohols do have a carbohydrate content, but they are processed by the body very differently than normal carbs, which is what makes most of them suitable for those doing keto.

Sugar alcohols are difficult for the body to digest and tend to pass through the stomach and intestines without much effect on blood sugar and insulin levels.3 Although this is generally true, it is important to pay attention when consuming Isomalt and other sugar alcohols to ensure they don’t affect insulin or ketosis on a personal level.

Isomalt: Keto Net Carbs and Nutritional Information

Isomalt has a similar carb to calorie ratio as sugar; while sugar is 100% carbohydrates per serving, isomalt is 97% carbohydrates. What stands out when taking a closer look at the nutrition facts per 100 grams of both isomalt and sugar, is the large calorie difference and the amount of sugar alcohols in isomalt vs sugar. 

Nutrition  Amount of Isomalt Sugar
Calories 190 387
Carbohydrates 97 g 100 g
Sugar Alcohols 97 g 0 g

Ultimately, what this shows is that isomalt is a better choice over sugar because it is 197 less calories than its counterpart as well as being a sugar alcohol, which reduces its glycemic index to 2 instead of 65, like sugar.

Downsides of Isomalt and Other Sugar Alcohols

Not all sugar alcohols have the same nutritional profile and can range drastically from 0 to 3 calories per gram and have a glycemic index of 0 to 45. While isomalt is at the lower range, it still has values that can potentially affect blood glucose and should be monitored closely.

Another thing to be cautious because sugar alcohols aren’t broken down like a majority of food, if too much ingested, there can be severe gastrointestinal consequences in the form of stomach pain, bloating, gas, and diarrhea.3

5 Alternatives to Isomalt That Won’t Affect Blood Sugar (Best Keto Sweeteners That Don’t Spike Insulin) 

Although isomalt is a better choice than sugar, there are several isomalt keto friendly competitors that have little to no calories and a glycemic index of 0, which means it will not affect blood sugar or spike insulin. Not only are they nutritionally better, their percentage of sweetness is higher as well. 

The following list contains no synthetic or processed sweeteners; only natural sweeteners which are derived from certain plants and a single sugar alcohol which have very little little side effects and have been touted by many in the keto community. So after deciding to stick with keto and finding what vitamins help with weight loss, consider using the following suggestions to find a favorite sugar substitute to optimize progress.

#1 – Erythritol

Another sugar alcohol similar to isomalt is erythritol. Unlike isomalt, however, erythritol has a glycemic index of 0, a sweetness profile of up to 80%, and negligible calories.4 Erythritol contains .2 calories per gram which equates to less than 5 calories (1.6 to be exact) per serving size; so, according to the FDA, it is considered a calorie free food and can be labeled as such.5

One Serving of Erythritol = 2 Teaspoons (8 grams)

  • Calories: 0
  • Carbohydrates: 8
  • Sugar Alcohols: 8
  • Fiber: 0

Because of erythritol’s qualities, it is a great substitute for sugar and can be seen in the ingredients list for keto chocolate, keto ice cream, low carb baked goods, as well as many other low carb or carb free foods.

What to watch out for

As mentioned above, sugar alcohols are not processed well, or at all, in the gut and intestines. Although erythritol doesn’t have near the effect of some sugar alcohols on the digestive tract, each body is different. So, before polishing off an entire pint of keto ice cream loaded with this sugar substitute, it might serve consumers to be cautious when consuming erythritol for the first few times to make sure there is no stomach upset.

Secondly, it is common to see erythritol blends, which means before adding it to the grocery cart, ensure it is not blended with caloric sweeteners. Some blends are acceptable and are mixed with some common keto sweeteners (which will be seen below), but make sure to avoid the baking blend which includes erythritol and sugar.

#2 – Inulin

While not actually a sweetener, inulin has functionality as a replacement for sugar even though it is actually a prebiotic fiber. It can be derived from many plant sources, but most notably, the chicory root. As a fiber, the body’s digestive enzyme cannot be broken down, but when passing through the bowels, it promotes the growth of healthy bacterias.

Inulin has a glycemic index of 0 but only has 30% to 50% the sweetness of sugar. For those who don’t love an overwhelmingly sweet taste, this prebiotic fiber that doubles as a replacement for sucrose is perfect.6

One Serving of Inulin = 3/4 Teaspoons (3 g)

  • Calories: 5
  • Carbohydrates: 3
  • Sugar Alcohols: 0
  • Fiber: 3

Inulin is easily dissolvable in warm liquids and also performs well in baking, which for just 5 calories per serving and no reaction from blood sugar, this sugar substitute seems to have an array of benefits. 

Some suggest adding a very small portion of a different natural sweetener to boost inulin’s flavor profile if it’s not quite sweet enough, but if dieters are looking for a 2 in 1 solution in their daily regimen, this fiber and sweetener combo might be a winner. 

In fact, when looking at a comparison of shakeology vs slimfast, slimfast is ingredient after ingredient of processed chemicals while shakeology takes advantage of natural sweeteners, such as inulin, to make it wholesome and tasty.

What to watch out for:

Inulin is not usually ingested in large quantities, but because it is a fiber, there is a chance that it could cause stomach distress if too much is consumed. Like with most new food items, starting with a small portion and slowly increasing might be best.

#3 – Monk Fruit: Our Favorite Isomalt Keto Substitute 

When looking to reduce sugar consumption, an all natural sweetener, such as monk fruit sweetener, which is extracted from the lo han guo fruit, might be a choice to consider. Between 100 and 250 times sweeter than sugar, just a fraction of this sugar substitute can be used while adding 0 calories or carbohydrates to a meal or snack.7

One Serving of Monk Fruit Extract = 1/8 Teaspoons (.32 g)

  • Calories: 0
  • Carbohydrates: 0
  • Sugar Alcohols: 0
  • Fiber: 0

Monk fruit extract is perfect for sweetening things like drinks and smoothies because of the miniscule amount needed along with the ability to easily dissolve; so, when looking to sweeten drinks to reduce belly fat in 4 days, monk fruit extract may be the key. However, it may not be ideal for baking because it could change the texture outcome due to the drastic reduction of volume needed to sweeten it.

What to watch out for:

Because of monk fruit extract’s intense sweetness, it is common to find it in a blend with a less sweet sugar substitute, such as erythritol. While there are little recorded negative side effects in regards to monk fruit extract, combining it with a different low calorie sweetener might affect it. 

#4 – Stevia

Extracted from leaves of the stevia plant, stevia is up to 300 times sweeter than granulated sugar, but in a stark comparison to sugar, it has 0 calories and 0 carbohydrates and is completely natural. Approved by most diets, including keto, due to its zero impact on blood sugar and insulin, stevia is a top choice of substitutes when it comes to figuring out how to stop eating junk food and sugar.7

One Serving of Stevia Leaf Extract = 1/32 Teaspoons (.14 g)

  • Calories: 0
  • Carbohydrates: 0
  • Sugar Alcohols: 0
  • Fiber: 0

Stevia has become popular throughout the years and can be found in certain diet sodas, baked goods, chocolate, candy, plus many more foods and beverages. 1/32 of a teaspoon of stevia leaf extract is equal to 1 teaspoon of granulated sugar; so even though some adjustments may need to be done when using stevia in cooking, the benefits greatly outweigh the cons. 

What to watch out for:

Use caution when purchasing stevia at the grocery store and online; like previous other sweeteners, stevia is often sold as a blend and while some use keto approved substitutes, others use simple sugars, such as maltodextrin, that can affect ketosis or insulin. To ensure that the product purchased is pure stevia extract, make sure the ingredients only list stevia leaf extract.

#5 – Allulose

As a new kid on the block when it comes to sugar substitutes, allulose quickly found footing in the dieting world with its no calorie nutritional profile and glycemic index of 0. Derived from sugar found from multiple sources such as raisins and figs, allulose only contains .4 calories. While not a fiber or a sugar alcohol, allulose technically does contain carbohydrates, but is processed by the body very similarly to a sugar alcohol and doesn’t affect blood sugar or ketosis.8

One Serving of Allulose = 1 Teaspoon (4 g)

  • Calories: 0
  • Carbohydrates: 4
  • Sugar Alcohols: 0
  • Fiber: 0

Allulose can be seen in ingredients lists from keto ice cream, bread, tortillas, and various other treats. Because its sweetness is only 70% of sugars, it is often combined with erythritol to give it a bit of a flavor boost.8

What to watch out for:

Like a majority of these keto-approved sweeteners, allulose can be seen combined with various other sweeteners. A majority of the time, as mentioned directly above, it is blended with erythritol; but before adding a container of allulose to the pantry for daily use, make sure the label doesn’t contain any nasty ingredients.

What Sugar Substitutes to Avoid While Following Keto

The five isomalt keto friendly alternatives listed above can all be good choices for those following a low carb diet, but what sugar substitutes should be avoided while following keto? 

There are many natural sweeteners that exist that are acknowledged by the health conscious community, but that doesn’t mean they are low carb, which ultimately makes them a poor choice for those on keto or trying to control their blood glucose levels. Don’t let a 30 day weight loss challenge go to waste and think about kicking these following sweeteners to the curb.

  • Honey – This all natural sweetener may be a good option for those wanting to cut out processed sugars, for the keto crowd, honey comes in at 17 carbs per 1 tablespoon.
  • Coconut Sugar – While coconut sugar does have a small amount of calcium and potassium, it also has 9 carbohydrates in each 2.5 teaspoon serving.
  • Date Sugar – Those looking for an all natural sweetener might gravitate toward date sugar, this substitute has 4 net carbs per 2 teaspoons, which is a large portion of carbs for those on keto.
  • Agave – This liquid sweetener derived from the agave plant is similar to honey; while it may be better than processed sugar, 16 carbs for 1 tablespoon cannot be ignored.

When on any type of diet plan, one of the best weight loss hacks for lazy girls and guys is finding alternatives to things that are beloved because it is an important way to keep up momentum and have continued success. Completely cutting out sweets for many people is unrealistic, so it is important to find sugar and isomalt keto friendly alternatives, like those listed above, which can help satisfy cravings in a healthy way.


1Aguilar, A. (2018, August 6). What are sugar alcohols? – MSU Extension. MSU College of Agriculture and Natural Resources. Retrieved November 8, 2022, from <>

2Harvard T.H. Chan School of Public Health. (n.d.). Diet Review: Ketogenic Diet for Weight Loss | The Nutrition Source | Harvard T.H. Chan School of Public Health. Harvard T.H. Chan School of Public Health. Retrieved November 8, 2022, from <>

3University of California, San Francisco. (2022). Counting Sugar Alcohols. Diabetes Education Online. Retrieved November 8, 2022, from <>

4Regnat, K., Mach, R.L., & Mach-Aigner, A.R. (2017, December 1). Erythritol as sweetener—wherefrom and whereto? – PMC. NCBI. Retrieved November 8, 2022, from <>

5National Library of Medicine. (n.d.). FDA Regulatory Requirements for Nutrient Content Claims – Front-of-Package Nutrition Rating Systems and Symbols. NCBI. Retrieved November 8, 2022, from <>

6National Library of Medicine. (n.d.). Inulin | C228H382O191. PubChem. Retrieved November 8, 2022, from <>

7Anderson, E., & Li, J. (2019, October 21). Sweetener – Stevia & Monk Fruit Sweeteners – Center for Research on Ingredient Safety. MSU College of Agriculture and Natural Resources. Retrieved November 8, 2022, from <>

8Xia, Y., Cheng, Q., Mu, W., Hu, X., Sun, Z., Qiu, Y., Liu, X., & Wang, Z. (2021, September 15). Research Advances of d-allulose: An Overview of Physiological Functions, Enzymatic Biotransformation Technologies, and Production Processes. NCBI. Retrieved November 8, 2022, from <>

About the Author


Nathan has been a fitness enthusiast for the past 12 years and jumps between several types of training such as bodybuilding, powerlifting, cycling, gymnastics, and backcountry hiking. Due to the varying caloric needs of numerous sports, he has cycled between all types of diets and currently eats a whole food diet. In addition, Nathan lives with several injuries such as hip impingement, spondylolisthesis, and scoliosis, so he underwent self-rehabilitation and no longer lives with debilitating pain.