When you are on the keto diet you should avoid or cut out as much as possible the consumption of carbs. This in turn means that you can’t use sugars for sweetening but have to look at other alternatives.
There are a number of sweeteners you can use. Some of them are artificial but you also have quite a few natural sweeteners at your disposal.
As the heading above already indicates, there are a few classifications of sweeteners. Some are good choices to use on a keto diet or any low-carb diet while others are not what you should use.
The best choices for sweeteners on keto are to use types that are natural and don’t cause insulin or blood sugar spikes. On top of that they should certainly sweeten your dish with a good overall taste profile.
One important aspect is that you get sweeteners that are pure. In many cases if you purchase packaged and ready-to-use sweeteners then you will find fillers in the product. These fillers are often maltodextrin or dextrose or others like these which in turn will spike your blood sugars. They also often add carbs to the sweetening product which is another good reason to stay away from them!
Before we dive deeper into the world of low-carb approved (and avoided) sweeteners, let’s first have a look at what you have to consider when trying to find the perfect type.
There’s a ton of sweeteners on the market. Yet, not each kind is considered to be a good match for the keto diet. Why is that? What do you have to consider when looking at the different sweeteners? Let’s get into this first!
You often find the abbreviation GI which represents the glycemic index. It refers to the relative amount by which a specific food raises your blood sugars. The index runs from 0 to 100.
Zero is a food that does not raise your blood sugar and insulin level when you consume it. A level of 100 is assigned to a food that dramatically raises your insulin and blood sugar values!
A keto diet is based on you staying in ketosis. That means you want to use sweeteners that don’t affect your blood sugar and insulin levels so you stay in ketosis. So, any sweetener with a GI of 0 (or close to it) will be considered keto friendly.
The keto diet is a low carb diet so the one thing you want to avoid are any kind of sugars. Keto tries to reduce, or practically eliminate, carbohydrates so your body starts to burn ketones.
That can only work if you minimize your carb intake and as such any kind of sugar is a no-no! This does include pretty much any kind of fruit which are typically quite high in sugars.
Keto is a low-carb diet. Therefore, no sweeteners that contain carbs should be part of the diet. Otherwise, you’ll drop out of ketosis and won’t reap the benefits of keto.
The following table shows the typical values for each of the sweeteners we look at in further detail below.
Net Carbs for 100g
Calories for 100g
0 - 5
20 - 40
0 - 25
0 - 100
0 - 80
Below is a description of any of the commonly used sweeteners you can easily find at your natural food store or your supermarket. Most all of them can also be gotten online through retailers like Amazon.
The first kind of sweeteners to have a closer look at are the natural kinds. Typically, these are the ones you want to consider most but you have to keep in mind that they can have a sort of an aftertaste that you have to get accustomed to if you used sugar before.
Stevia has become a more and more commonly used sweetener in the last few years. It’s completely nutrient free and has tremendously grown in popularity as a natural alternative to many synthetic sweeteners.
Stevia is also referred to as sugar leaf, candyleaf or sweetleaf. It’s an extract of the herb Stevia rebaudiana that is in the sunflower family. The extract has zero calories, no carbs and a glycemic index of 0 in its pure form. It also is around 200 to 300 times sweeter compared to table sugar.
Besides not raising blood sugars and causing insulin spikes, Stevia has actually additional health benefits when you consume it. Studies have shown a positive impact on insulin and blood sugar levels after eating meals that were prepared with stevia.
Stevia in addition has shown benefits with regards to anti-inflammatory and anti-oxidant properties. Studies have indicated that it can help to reduce oxidative stress and oxidative DNA damage.
You typically will find stevia in either liquid or powder form. In any case, but usually more common in the powdered form, you will find fillers that are added. These are often maltodextrin, dextrose, synthetic sweeteners or even cane sugar. Make sure to read the label to know what is in the package as some of these ingredients might contain carbs or raise blood sugars and insulin. In those cases the Stevia mix would be harmful to your keto diet!
Overall, pure Stevia is pretty much the best sweetening ingredient you can get to match your keto diet requirements.
Allulose is a rather new sweetener on the market. It is one of the most sugar-like sweeteners that contains less calories than sugar does. It is about 70% as sweet as table sugar yet with less calories and a zero glycemic index with practically no carbs.
Allulose is also referred to as D-psicose. It is composed of a simple sugar (monosaccharide) which can be found in certain fruits (raisins, figs, jackfruit) as well as other sugar based sweeteners like brown sugar or maple syrup. As it is naturally only found in a few foods it is also classified as a ‘rare sugar’.
You might be wondering why a sweetener that contains carbs has a zero GI. The reason is that our bodies cannot convert the carbs in Allulose. You eat them and they get excreted without being absorbed.
Most of the carb content is absorbed into the blood stream through your digestive system. However, it is then excreted through your urine and is not converted into fuel.
Another positive side effect is that it resists fermentation by the bacteria in your gut and as such bloating and gas are minimized when you consume it. It’s also low in calories as it has only around 1/10 of the calories of table sugar.
There are a number of studies that have shown that Allulose has a positive impact on blood sugar levels and insulin. This in combination with not having a significant carb content makes it a great sweetener when you’re on the Keto diet.
You might want to slow down though in thinking that Allulose might be the only sweetener you should use. While the FDA classifies it as being generally recognized as safe (GRAS). Yet, there have not been too many studies that researched the longer term impact on the human body. All research so far indicates that it’s safe to use.
Inulin is a sweetener that is most often extracted from the chicory root. The commercially best known brand is ‘Just Like Sugar’ which does add other ingredients including Vitamin C and orange peel as well as calcium.
The package label claims that it comes with basically no carbs and calories which is not completely true. Studies have shown that we do absorb some of it through our digestion. Thus, take the label information with a grain of salt as it’s not completely free of carbs or calories!
Inulin can easily be mixed with other sweeteners if you desire. It also does caramelize similar to sugar and you won’t get a strange after taste like you end up getting with some other sweeteners.
Inulin can also be found in other fruits and vegetables besides the chicory root. You can find it in banana, garlic, Jerusalem artichoke and others like onion, yacon or jicama. Some of the sweeteners you can buy could be made from any of those and you want to always make sure that you only purchase sweeteners that are not blended with other sweeteners or have any carb-laden ingredients on top of it.
It can lead to bloating and have a laxative effect if you consume large amounts on a daily basis. Regular amounts have shown on adverse side-effects. Studies have shown that Inulin can improve glycemic and antioxidant indexes in patients with type 2 diabetes.
Monk fruit is native to northern Thailand and China. It’s also called Luo Han Guo and is also sometimes referred to as the longevity fruit. It’s being used in traditional Chinese medicine to treat diabetes and obesity.
It’s about 300 times sweeter compared to sugar which puts it in the same range as Stevia. It does not have a bitter aftertaste that many of the available stevia products have. Similar to Stevia it does provide the sweetening without blood sugar or insulin spikes.
Monk fruit has been used for hundreds of years and has shown no adverse health effects. It is a pretty rare sweetener though and if you’re trying to get it in its pure form you will be surprised at cost and that it’s not that easy to find. Many of the available products containing Monk Fruit have fillers and additional sweeteners that can at times contain carbs!
Tagatose is a simple sugar or monosaccharide. It is found in dairy, cocoa and fruits. It’s arrangement of atoms is different than that of sugar and as such the body metabolizes it differently.
Similar to Erythritol, it has a cooling effect. Yet, you can caramelize it similar to sugar. Compared to Xylitol it has a lower glycemic index. You can at times have a hard time finding it though.
Tagatose does not have a GI of 0. It’s glycemic index is 3 and as such it does raise blood sugar levels. Yet, it certainly has a much smaller GI than sugar so it still is a good sweetener for the keto diet.
In any low carb diet you might want to use Tagatose sparingly. It is not carb free so you want to make sure to not overdo it. However, it does inhibit digestive enzymes as well as the degradation of carbohydrates in the gut. The result is that few(er) carbs get absorbed in the body. That’s why the amount of net carbs for Tagatose is very low. You can mix it with other low GI sweeteners though to further decrease the amount of overall carbs.
Next in the list of keto friendly sweeteners are the different kinds of sugar alcohol you can get. The best known and most used for low carb diets is Erythritol. But, it’s not the only sugar alcohol you can find that is good to use when you’re on keto. We listed a number of them even though some of them are honestly a little far out there with regards to availability or price.
Erythritol is the most commonly used sugar alcohol and that for good reasons. It is found in fruits and vegetables and for commercial use is most times extracted from corn.
It has a glycemic index of 0 and is low in calories at about 0.24 calories per gram. That’s only around 6% of table sugar! It’s a little less sweet than sugar so you typically will need to use more of it to reach the same sweetness you get from sugar.
Many sugar alcohols can create some digestive discomfort as the human body cannot break them down. That can lead to bloating and mild cramping. This is not the case with erythritol. Pretty much all of it gets absorbed into the bloodstream in the small intestine. It is then filtered out through your kidneys and you end up excreting it through your urine. This means that it won’t affect your colon and as such can’t lead to bloating or cramping.
Erythritol can be purchased online and can be gotten in its pure form. You can use it for pretty much any kind of sweetening except that it doesn’t caramelize like sugar does! When you’re looking to buy it make sure to get pure erythritol and not a version that has fillers which in turn might contain carbs and spike your blood sugar!
Mannitol is a lesser known and used sweetener that is based on sugar alcohol. It has a glycemic index of 0 and has about 1.5 calories per gram.
It has shown in research that it might be part of a potential treatment for Parkinson’s disease. It is also used for medication for brain injuries.
Xylitol is another sugar alcohol that can be found in many fruits and vegetables. It tastes like sugar but comes with less calories. Its glycemic index is 13 so it does spike your blood sugar levels slightly yet by far not as much as sugar does! It has around 3 calories per gram and is a little sweeter than sugar.
A good side effect of xylitol is that it can improve dental health. It’s not usable by the bad bacteria in your mouth and as such starves them. The result can be healthier teeth and gums. You can therefore find it quite often in whitening chewing gum!
The biggest side effect that is reported is potential stomach discomfort when using Xylitol. When consumed in larger amounts it can also lead to diarrhea.
Xylitol can safely be used to sweeten pretty much any food. However, if you have dogs then make sure NOT to use it. Even small amounts are very poisonous for dogs and can be fatal.
Maltitol is overall very similar in taste and sweetness to sugar. It is used in many commonly available foods that state that they are ‘sugar-free’. It has a glycemic index of 36 and around half the calories of sugar.
It’s a good marketing ploy for companies to use Maltitol as a sugar replacement and then call the product ‘sugar free’ or ‘zero carbs’, etc. It can be done as the carbs in Maltitol do not count into the carbs that are counted based on our regulations. It will affect your blood sugar and as such you want to avoid it if possible!
In short, it’s widely used but it does spike your blood sugars. Based on this it’s not a recommended sugar replacement when you are on a low-carb diet like keto or Atkins. However, as it has less calories and a lower GI than sugar it can be an effective method to fight weight if you don’t overuse it. There are better alternatives though.
There’s a whole load of other sugar alcohols that can be used instead of sugar. Yet, almost all of them will cause your blood sugar levels to spike. In keto and other low carb diets, this is to be avoided and as such these sugar alcohols like Sorbitol, Lactitol, Glycerol, etc. are not considered a good choice as a sweetener.
For the lack of a better word we call these ‘un-pure’ as they contain fillers and other sweeteners. You at times can find sweeteners that are based on erythritol but then also contain oligosaccharides.
These are typically found in fruits and vegetables and are indigestible carbs similar to what you for example find in Inulin. They do have a low glycemic index but that depends on the kind of oligosaccharides that is used.
A commonly used sweetener that combines erythritol with oligosaccharides is Swerve. They use it to round out the overall taste and structure of their product without causing a lot of negative impact.
When you’re on keto it’s typically ok to use such sweetener products. Just don’t overdo it. Smaller amounts will practically not cause a large blood sugar or insulin spike that could take you out of ketosis.
The last category of sweeteners that we’re having a closer look at are the synthetic sweeteners that are available. There are quite a few that are well known and have been around for many years.
There a some controversy around sucralose with regards to its glycemic index. In its pure form (usually liquid) it has a GI of 0. However, looking at the most common powder variant which is sold under the brand Splenda, you’ll get an average glycemic index that’s around 80!
That’s higher than regular sugar and you’re pretty much guaranteed to see a blood sugar and insulin spike as a reaction to consuming it. On any low carb diet, including keto, you want to avoid the powdered version of sucralose! These powdered versions usually have fillers like maltodextrin which in turn increases the glycemic index.
In its liquid form the GI is 0. Be careful in that case though as liquid sucralose is around 600 times sweeter than sugar. You just need a tiny amount for sweetening or you combine it with other sugar substitutes like erythritol when you want to bake with it.
Aspartame is an overall very controversial sweetener to use. This, over the years also made it one of the most researched artificial sweeteners you can find. It has been in use for decades and is often found in many diet drinks as well as low carb products. Its GI is 0 which makes it a valid choice for low carb products.
Over the years it has been associated as the reason for many health issues ranging from blindness to multiple sclerosis and a host of others. Due to this it has been studied and researched extremely well with no findings that any of these ailments would be caused by Aspartame.
Besides the somewhat shady reputation, Aspartame can be used well in cold drinks and dishes. It does not work well for baking or cooking. It breaks down at higher temperatures and causes a bitterness and an aftertaste.
Even though it has never shown to be a health concern it’s not the best sweetener to use. Its use is limited to cold meals and drinks and you find better products that can cover the overall range of cold to hot with less potential issues.
Saccharin has been around for a long time. First references date back to more than 150 years ago. Over the years its use has declined steadily and it’s not a very commonly used sweetener these days. Its glycemic index is pretty much all over the place as you usually only get it mixed with fillers which add different GI’s to the overall product.
The decline of Saccharin started in the 1970’s when all products that contained it had to have a warning label on it that it had the potential to cause cancer in humans and animals. Decades later the warning got removed because the statements couldn’t be validated. However, many people today prefer to avoid this sweetener for those reasons.
Similar to Aspartame, this is a sweetener that works well for cold foods and drinks but is not useful at all for cooking and baking. During the heating process the sweetener breaks down and creates a very bitter after taste.
This is yet another synthetic sweetener that can be found in quite a few diet drinks, low calorie/low carb goods as well as in some chewing gums and even toothpaste. Many times you won’t find it as the only sweetener but in combination with others.
It has a glycemic index of 0 and is around 200 times more sweet than sugar. The body does not break it down and as such it does also come as a zero calorie sweetener.
In addition it also is pretty much the only artificial sweetener that you can use for cooking and baking. It does not break down at higher temperatures which means that it stays sweet and doesn’t develop some strange taste.
There are quite a lot of different sweeteners you can use when you’re on a keto or otherwise low-carb diet. Looking at the large number of natural sweeteners and sugar alcohols you can use, there’s no reason why to even consider synthetic sweeteners.
In our opinion you want to go with any of the natural sweeteners we list above or use Erythritol for cold or warm dishes and drinks. This will keep your blood sugar and insulin levels in check and help you to stay in ketosis!