Home Weight Loss Sugar and Sweeteners on the Keto Diet: What You Need to Know

Sugar and Sweeteners on the Keto Diet: What You Need to Know

When your body is in ketosis, it’s in a metabolic state that causes your body to become more efficient in breaking down fat stored in the body instead of carbs to produce energy. It also turns fat into ketones in the liver, which help to supply energy to the brain. You reach ketosis by following a ketogenic diet, which means following a low-carb diet that replaces carbs with fat. It also means following a low-sugar or no-sugar diet. Ketogenic diets can lead to reductions in blood sugar and insulin levels and other health benefits, including weight loss.

Sugar and Ketosis

Sugar is everywhere, so it’s difficult to follow an entirely sugar-free diet, but it’s possible to cut most sugar out of your diet. People should generally try to consume up about 20 to 30 grams of carbohydrates per day on keto. Refined sugar counts as a carbohydrate. You can consume sugar while on the diet as long as you limit it as much as possible to avoid the impact carbohydrates have on spiking blood sugar and insulin levels. The ideal amount of carbs consumed from sugar on the diet is 0 grams - and this is where carb-free sugar alternatives come into play.

When choosing which types of sweeteners you consume, it’s worth noting its glycemic index. What does this mean? The glycemic index (GI) ranges from 0 to 100, with pure glucose ranking at 100. It indicates three things: the number of carbs present; the type of carbs present; the presence of other substances that slow the metabolism of carbohydrates.

Basically, the glycemic index tells us how quickly or slowly the body absorbs these sugars. Sugars that are lower on the glycemic index means that the body absorbs them slower and that they do not cause significant increases in blood sugar and insulin levels. Foods with a high glycemic index, typically at 70 or higher, can cause insulin resistance, which can lead to weight gain, diabetes, and inflammation if consumed in excess.

All sweeteners, even artificial ones, set off cravings. Studies show that all types of sweeteners increase your desire to eat sweets, so you’re more likely to eat too much - and that makes it harder to lose weight. So, even sweeteners that are safe to consume on the diet should be used sparingly.

Let’s take a look at how sugar consumption affects ketosis.

How Much Sugar Will Kick You Out of Ketosis?

The problem with sugar and the keto diet is that they are not friends. If you consume sugar in sufficient amounts, your body will decide that it has enough glucose to use as fuel (or energy) and that will kick your body out of ketosis.

How much sugar can you have on keto? The recommended daily sugar intake on keto is zero grams because consuming sugar will quickly use up your carbohydrate allowance for the day and possibly kick your body out of ketosis. For instance, as mentioned, you’ll want to consume about 20 to 30 grams of carbs per day. A single tablespoon of sugar contains 12.5 grams of carbs alone, and a tablespoon of honey is even worse at 17 grams of carbs.

While you’ll want to avoid foods that contain refined sugar and honey while trying to keep your body in ketosis, this does not mean you can’t indulge your sweet tooth. It just means you’ll want to avoid certain foods.

You’ll want to eliminate the following foods while you’re sticking with a keto diet:

  • Wheat, rice, corn or cereals
  • Potatoes, yams and other starchy vegetables
  • ​Excessive amounts of most fresh fruits including bananas, apples, and oranges
  • Sugar and natural sweeteners like honey and maple syrup

While these foods don’t adhere to keto, you can still indulge your sweet tooth with fruits and sweeteners that are. Let’s examine some alternative options and the pros and cons of consuming them on a ketogenic diet.

Is Coconut Sugar Keto?

It would seem like coconut sugar might be okay to consume on keto, but it isn’t. Coconut sugar is a natural, unrefined sugar that is derived from the sap of coconut palm trees. It doesn’t contain any preservatives or additives, and it is lower on the glycemic index than refined sugar: coconut sugar has a glycemic index of 35, while refined sugar has a glycemic index of 60.

However, one tablespoon of coconut sugar contains 12 grams of carbohydrates, about the same as one tablespoon of refined sugar. While coconut sugar is a healthy alternative to refined sugar, it is not keto-friendly.

What About Brown Sugar?

Brown sugar is similar to white cane sugar, but the process by which it is made is slightly different: It’s made directly from boiled sugar cane juice, which is then left to cool and crystallize over a period of time. Brown sugar also contains between three percent and seven percent molasses, which gives it its color. Molasses contains vitamins and minerals including vitamin B3, vitamin B6, thiamine, calcium, magnesium, iron, sodium and potassium, so brown sugar does contain these key vitamins and minerals, but in minimal amounts.

While there are benefits to using and consuming brown sugar, they are outweighed by the sugar element. Brown sugar, like white cane sugar, is high in carbohydrates. A typical serving of brown sugar is two tablespoons, amounting to about 96 calories, 22 grams of carbs, 22 grams of sugar, zero grams of fat and zero grams of protein. In the standard ketogenic diet, the average daily limit for carbohydrates consumption is 20 to 50 grams. Just one serving of brown sugar could put you into your carb limit for the day, making it not a very keto-friendly option.

Is Fruit Keto-Friendly?

Certain fruits work better for keto than others. Berries generally have the lowest amount of carbs. Raspberries and blackberries contain 5 grams of carbs per 100 grams, and strawberries contain 6 grams of carbs for the same serving size. Blueberries should be eaten sparingly, as they contain 12 grams of carbs per 100 grams (which amounts to about three handfuls of berries).

Generally speaking, the larger or sweeter the fruit, the greater the number of carbohydrates that fruit contains. For instance, a mango contains about 13 grams of carbs, a pineapple has about 12 grams of carbs and a banana contains 20 grams of carbs. Consuming a medium-sized banana could put you close to your carb limit for an entire day on a keto diet.

Fruit is healthy to eat, but consuming a lot of fruit results in consuming a lot of sugar. Stick with berries because they are lowest in carbs and allow you to easily stay in ketosis.  

Using “Keto Sweeteners” - Is There a Downside?

There is a variety of sugar alternatives one can use, but which ones are considered safe keto sugars? Let’s take a look at commonly used artificial sweeteners, sugar alcohols, and natural sweeteners that are considered "keto sweeteners" along with the pros and cons of using them.

Artificial Sweeteners


Sucralose is an artificial sweetener that is made from cane sugar that has been modified with chlorine atoms. How is this done? The cane sugar is put through a chlorination process that replaces three molecules in the sugar with chlorine atoms. The result is an ingredient that is not digestible and over 600 times sweeter than cane sugar. This means that your brain thinks it is consuming an enormous amount of sugar at once and this approach often leads to increased and intense sugar cravings throughout the day.

Sucralose is technically low on the glycemic index at 0, and it does not affect blood sugar. However, while consuming a sucralose-based sweetener may curb a sugar craving temporarily, consuming sucralose triggers a few things that can cause fat absorption: it can cause further cravings; sucralose can increase the rate of intestinal glucose absorption; it can signal the beta cells in the pancreas to produce insulin. All three of these are factors which could lead to weight gain.


Maltodextrin is a water-soluble white powder that can be made from corn, wheat, rice, or potato starch, and it is highly processed. It contains less than 20 percent sugar, which is why it is commonly used as a sugar substitute. It’s also used as a filler in foods to prolong the shelf life of packaged foods. It may contain monosodium glutamate (MSG) which is not required by the FDA to be labeled.

Maltodextrin has about the same amount of calories as granulated sugar or table sugar (sucrose) at 4 calories per gram, so it is not lower in calories than table sugar. It also ranks rather high on the glycemic index at between 85 and 105. Fillers such as maltodextrin are also carb heavy, so consuming products with maltodextrin may prevent you from reaching ketosis.


Dextrose is a type of carbohydrate called a simple sugar. Plants store it as starch, and this is why it is easily extracted from corn starch to create a powdered sweetener that is often used in baking products, processed foods, and corn syrup. Simple sugars can impact blood sugar to raise it rather quickly and often have little nutritional value.

Products that are typically made of simple sugars include honey, pasta, and refined sugar, all of which should be avoided while on a keto diet. Dextrose ranks very high at 100 on the glycemic index and should be consumed with caution.


Aspartame is a chemically-derived artificial sweetener that is found in diet sodas and other processed, sugar-free food products. It contains 4 calories per gram and it is not a calorie-free product. However, one 12 oz. can of Diet Coke contains 200 mg of aspartame, which amounts to 0.8 calories, and one pack of Equal has 37 mg of aspartame, which is 0.15 calories. In other words, the calorie count of aspartame in foods is typically quite minimal. It ranks at zero on the glycemic index and it is not known to affect blood sugar and insulin levels in the short term.

However, there are drawbacks to consuming aspartame. It has been found to be about 200 times sweeter than sucrose which, like sucralose, can trick the body into thinking it’s consumed a lot more sugar and lead to more cravings. Also, when aspartame is metabolized in the body, one of the chemicals it breaks down into is phenylalanine, which can be toxic to some people. In a few studies, aspartame was also linked to cancer, but only when ingested in extremely high doses. There is a limit to the recommended daily consumption of aspartame: the FDA has deemed it safe to consume a maximum of 50 mg per kilogram of body weight per day.


Splenda is an artificial sweetener in powder form that contains sucralose. While pure sucralose has zero calories, Splenda cannot claim to be that because It also contains the thickening agents like maltodextrin and dextrose, which are a derived form of glucose.

One packet of Splenda has about 3.75 calories. Though it ranks low on the glycemic index, the maltodextrin and dextrose in Splenda will impact blood sugar and insulin levels. It’s also worth noting that cooking with Splenda is dangerous: sucralose breaks down at high temperatures and turns into chemical compounds that have an unknown effect on human health.

Sugar Alcohols


Sorbitol is a sugar alcohol that is naturally found in certain fruits, including peaches, apples, pears, and prunes. However, the type of sorbitol used in foods is mostly made from corn syrup. Sorbitol is about 60 percent as sweet as table sugar (sucrose) and contains about 2.5 calories per gram. In addition, sorbitol does have an effect on blood sugar and insulin and should not be consumed in massive quantities.


Xylitol is naturally occurring and found in many fruits and vegetables, and it’s extracted from corn or birch wood. It’s similarly sweet to sugar and contains about 3 calories per gram. It can have positive health effects such as helping the body to absorb calcium and fighting cavities and tooth decay. While xylitol is considered a keto sweetener, it can cause diarrhea, gas, IBS, or GI distress, so it’s best to consume it in moderation.


Maltitol is also found in certain fruits and vegetables, and it’s almost as sweet as sugar - about 90 percent as sweet - and contains about 2.7 calories per gram. It is used as a substitute for sucralose because it contains half of the calories, it does not lead to tooth decay, and it has a lesser effect on blood glucose levels. Negative side effects of maltitol are similar to those caused by xylitol and include possible digestive problems.


Erythritol is naturally occurring in foods such as pears, melons, and grapes. It’s also created in large-scale production when a type of yeast ferments glucose from corn starch or wheat starch.

It’s different in several ways from other sugar alcohols. Firstly, it contains fewer calories at just 0.24 calories per gram. It ranks quite low on the glycemic index at 1. It doesn’t cause any serious side effects, and it tastes similar to sugar, but it can cause digestive upset when eaten in high amounts.

Natural Sweeteners

Both Stevia and monk fruit are natural sweeteners that are made from concentrated components of plants instead of chlorinated sugar, like sucralose.


Stevia is an herb commonly known as the sugar leaf. It has zero calories, no sugars, no carbs, and it is about 250 to 300 times sweeter than sucrose. It’s not metabolized by the body and can help to lower blood sugar and insulin levels, decrease inflammation, and lower blood pressure.

Stevia doesn’t taste like sugar and has a bitter aftertaste to some users. Similarly to some sugar alcohols, it can cause digestive issues. When shopping for Stevia, be sure to read the ingredients labels before purchasing. While it is relatively easy to find liquid or powdered forms of Stevia that do not contain any fillers, some forms do contain carb-heavy fillers maltodextrin and dextrose.

Monk Fruit Sweetener

Monk fruit sweetener is natural and made by extracting plant chemicals from the monk fruit plant. It has no sugar, no carbs, no calories, and it does not impact blood sugar levels or cause digestive issues. Monk fruit sweetener has many health benefits: it contains anti-inflammatory properties, anti-obesity, and antidiabetic properties. It also has antimicrobial properties that can help you fight fungal infections.

It’s 200 to 300 times sweeter than table sugar, something to keep in mind when swapping out sugar for monk fruit sweetener in recipes. While monk fruit sweetener is available in powder form, these forms sometimes contain added ingredients such as maltodextrin and dextrose.

It’s best to stay away from monk fruit blends, so be sure to check the label before purchasing. Though it may not be as easy to find, it is best to use raw monk fruit, or try a liquid form that contains the raw form of monk fruit with a pure solution, also called a pure monk fruit extract, so you are still getting all of the nutrients and benefits of the fruit.

Helpful Tips to Curb Your Sweet Tooth

There are some things you can do to curb your cravings when that sweet tooth strikes:

1. Avoid artificial sweeteners.

Consuming artificial sweeteners won’t help curb cravings, it will intensely increase them. It’s best to avoid them and foods that contain them while you’re craving sugar.

2. Snack on some berries.

Have a handful of low-carb berries such as strawberries, raspberries, or blackberries to satisfy your sweet tooth.

3. Consider using Sweet Defeat.

Try using a Sweet Defeat lozenge to curb further sugar cravings. Sweet Defeat works on all sweeteners, so it helps you cut back on sugar - both natural and artificial sweeteners. It contains only five ingredients: Gymnema, zinc, mint, sorbitol, and spirulina. The Gymnema and zinc work to temporarily block the sweet taste receptors on your tastebuds so you can’t taste sweetness. It has a mint flavor and works within seconds, and it is clinically proven to stop cravings.

Bottom Line

Because there are so many different types of sugars and sugar substitutes, it’s important to learn about the different names for sugars and look out them when reading ingredient labels and nutrition labels to determine the nutritional content of what you’re buying and consuming.

Since artificial sweeteners can have negative side effects, promote cravings, and lead to weight gain, it is best to minimize the consumption of artificial sweeteners while following a keto diet and instead try to stick to consuming mostly whole foods. Sugar alcohols such as sorbitol and xylitol do not have an effect on blood sugar levels and may be used as an alternative to table sugar if needed, but they can cause GI issues if consumed in excess. Reach instead for natural sweeteners such as monk fruit to satisfy cravings, and consider using Sweet Defeat to help curb them.