Low-carb sweeteners, the best and the worst

What sweeteners are good on a low-carb diet? Check out the visual guide below. The ones to the left have less of an impact on people’s weight and blood sugar, the ones to the right are worse.
Keto sweeteners


The numbers above are based on the effect the sweetener has on blood sugar and insulin resistance, for an equal amount of sweetness compared to white sugar (100 percent pure sugar).1

If you’re aiming to stay low carb, try to avoid the sweeteners to the right in the picture above. The best options are to the left. We suggest primarily using , or .

Negative effects of all sweeteners

Note that while the sweeteners to the left above have small or non-existent direct effects on blood sugar levels (and weight), they still have other potential negative effects.

All sweeteners maintain cravings for sweet foods. Also, when added to caloric foods – e.g. a muffin – they result in a significantly increased feeling of reward when eating it. So by adding sweeteners to your foods you’re significantly increasing the risk that you’ll end up eating more than you need. This can slow down weight loss, or cause weight gain.

There are scientific studies showing that even adding non-caloric sweeteners to diet beverages may make it harder to lose weight.2

This means that all sweeteners, including the non-caloric ones above, have potentially negative effects. If you’re able to, you may be better off just avoiding all of them. Note that on a low-carb diet cravings for sugary foods tend to decrease over time, making it easier and easier to avoid them.

However, most people enjoy something sweet once in a while. If so, we suggest trying to do it only occasionally. Keep reading to learn more, and to be able to make better-informed choices.

Using sugar as a sweetener


Note that many sweeteners – white or brown sugar, maple syrup, coconut sugar and dates – have a number of exactly 100. This is because these sweeteners are made up of sugar. To get the same amount of sweetness as white sugar, you’ll get about the pretty much an identical effect of these sweeteners, on blood sugar, weight and insulin resistance.

Sugar is bad, no surprise, so these are bad options, especially if you’re on a low-carb diet. Avoid.

Even worse than sugar: fructose

Amazingly, there are sweeteners that are even worse than sugar. Regular sugar contains 50% glucose and 50% fructose. These sweeteners contain more fructose than glucose. While these sweeteners are slower to raise blood glucose – resulting in a deceptively low GI3 – they have even more harmful effects. Fructose in excess can result in fatty liver and insulin resistance, which increases the long-term negative effects of carbohydrates you eat later.


These sweeteners with excess fructose – high fructose corn syrup (soda), fruit juice concentrate, honey and agave syrup – can likely have a slightly worse long-term effect than pure sugar. Thus we give them a number of 100+. Worst of all, with the highest fructose content of all? Agave syrup.

This is not to say that sugar is good. Clearly sugar is potentially very bad. But these sugars are super sugars. They are not good options on a low-carb diet.


Our recommendations

As stated above, we see potential negative effects of all sweeteners. However, if you’re going to use one there are worse and less bad choices. Here are our top 3 suggestions:

Not-too-bad option #1: Stevia

SteviaStevia comes from the plant Stevia rebaudiana Bertoni, which is native to South America, where it has been used for several hundred years. Steviol glycosides extracted from the plant are responsible for its sweet taste.

  • Stevia doesn’t contain carbs or calories and does not raise blood sugar.
  • Stevia appears to be safe and nontoxic.
  • Stevia doesn’t really taste like sugar. It has a licorice-like flavor and an undeniable aftertaste when used in moderate to large mounts. Therefore, using it sparingly is recommended.
  • At least one study has indicated that large amounts of stevia might increase insulin secretion, possibly increasing fat storage and reducing stevia’s advantage over sugar.4

Sweetness: 200-350 times sweeter than table sugar.

Best choices: Liquid stevia or 100% pure powdered or granulated stevia. Note that packets of granulated stevia such as Stevia in the Raw contain the sugar dextrose. The brand Truvia instead contains added erythritol (see below).

Not-too-bad option #2: Erythritol

ErythritolErythritol is a sugar alcohol, a compound that resembles sugar but is only partially digested and absorbed by the body. Erythritol occurs naturally in plants like grapes, melons, and mushrooms in small amounts. However, as a commercial sweetener, it is usually made from fermented corn or cornstarch.

  • Erythritol provides almost zero calories and is virtually carb free. After being absorbed, it passes into the urine without being used by the body.
  • Erythritol might be helpful in preventing dental plaque and cavities, compared to other sweeteners.5
  • Erythritol has a noticeable cooling sensation on the tongue, particularly when used in large amounts.
  • Although it causes fewer digestive issues than most sugar alcohols, some people have reported bloating, gas and loose stools after consuming erythritol.
  • While absorbing erythritol into our blood and excreting it into the urine appears to be safe, there is likely some potential for unknown health risks.

Sweetness: 70% as sweet as table sugar.

Best choices: Organic granulated erythritol or erythritol and stevia blends.

Not-too-bad option #3: Xylitol

XylitolLike erythritol, xylitol is a sugar alcohol found in fruits and vegetables in small amounts. It is produced commercially from corn cobs or birch trees. Xylitol is one of the most frequently used sweeteners in sugar-free chewing gum and mouthwash.

Note however, that xylitol is only low carb, not zero carb. So it’s not a perfect choice on a keto low-carb diet (below 20 grams per day). The carbs quickly start to add up.

  • Xylitol has a low glycemic index of 13, and only 50% is absorbed in your small intestine. When used in small amounts, this results in a very minor impact on blood sugar and insulin levels.
  • Although its level of sweetness is identical to table sugar, xylitol contains 2.5 calories per gram, whereas sugar provides 4 calories per gram.
  • Like erythritol, it’s been shown to help prevent cavities, compared to other sweeteners.
  • Because 50% of xylitol is not absorbed but instead fermented by bacteria in your colon, it may cause digestive issues (gas, bloating etc.) when consumed in moderate to large amounts.
  • Although xylitol is safe for humans, it is toxic and potentially lethal for pets, like cats and dogs. If you use xylitol, make sure to keep it away from your animals.

Sweetness: Equivalent in sweetness to table sugar.

Best choices: Organic granulated xylitol made from birch.


The “zero-calorie” sweeteners that are almost 100% carbs

Artificial sweeteners

Packets of Stevia in the Raw, Equal, Sweet’n Low and Splenda are labeled “zero calories”, but this is just a trick. FDA rules allow servings under 1 gram of carbs and under 4 calories per serving to be labeled “zero calories”. So these manufacturers cleverly package about 0.9 grams of pure carbs (glucose/dextrose) – the filling agent that makes up almost 100% of the sweetener – mixed with a small dose of a more powerful artifical sweetener, for added sweetness.

Voilà, a package full of pure carbs, that can be labeled “zero” calories without risking a lawsuit.

The packages in fact contain almost 4 calories each, and almost a gram of carbs. While 0.9 grams of carbs may seem negligible for many people, on a low-carb diet it can matter. Especially if you use many packages a day. Ten packages equals almost half the daily carb limit on a keto diet.

So at least be aware of this. We don’t recommend these sweeteners because of the deceptive marketing. There are also lingering potential health concerns with many of these artificial sweeteners (e.g. aspartame, sucralose).

Why maltitol is not a good option

Maltitol is a sugar alcohol. It’s still the most common type used in “sugar-free” candy, desserts, and low-carb products because it’s considerably less expensive than erythritol, xylitol, and other sugar alcohols.

Maltitol is not a good choice for people on low-carb diets. About 40% of this sweetener is absorbed in the small intestine, raising blood sugar and insulin levels, especially in those with diabetes or prediabetes. It also provides about two-thirds as many calories as sugar, which is considerably more than most low-carb sweeteners.

In addition, the remaining 60% that’s not absorbed is fermented in the colon. Studies have shown that maltitol may cause significant gastrointestinal symptoms (gas, bloating, etc.), especially when consumed in amounts greater than 30 grams per day.6

Sweetness: About 80% of the sweetness of table sugar

Diet soft drinks – yes or no?

Diet sodasCan you drink diet soft drinks on a low-carb diet? Well, ideally you may want to avoid them. There are some clear negative effects with regular consumption, including that you’ll maintain cravings for sweet foods, and not retrain your palate to enjoy the natural, less intense sweetness of keto foods.

There’s also science suggesting that diet beverages may make it harder to lose weight, despite containing no calories.7 This could be due to hormonal effects, other effects on satiety signals, or effects on gut microbiota.

There are also other suspected, but unproven, health concerns with many of the artificial sweeteners used, like aspartame, acesulfame K and sucralose .8

However, if you feel you absolutely need to drink diet sodas, at least they will allow you to stay low carb. Regular soda, sweetened with sugar or HFCS, will very quickly result in a high carb intake, negating the positive effects of a low-carb diet.

A final word on low-carb sweeteners

While some sweeteners seem to be better than others, the best strategy for achieving optimal health and weight loss may be learning to enjoy real foods in their unsweetened state.

Although it might take a little time for your tastebuds to adapt, over time, you may discover a whole new appreciation for the subtle sweetness of natural, unprocessed foods.


Sweeteners with no calories generally do not result in weight gain when consumed in isolation or with water (in beverages). However, they could still do so if used in baked goods for example, resulting in wanting to eat more. And they do maintain people’s preference for an abnormally sweet taste, that can make it harder and less pleasurable to stick to a low-carb diet based on real foods. So our advice is still to ideally avoid them. But for weight loss and diabetes reversal, they are far less harmful than sugar.

Obesity 2018: Nonnutritive Sweeteners in Weight Management and Chronic Disease: A Review

The Journal of Nutrition 2018: Aspartame Consumption for 12 Weeks Does Not Affect Glycemia, Appetite, or Body Weight of Healthy, Lean Adults in a Randomized Controlled Trial

Sugar addiction

Do you find it almost impossible to consider giving up sweet foods? You can do it. Here’s something that may interest you, our course on sugar addiction and how to take back control.


Similar low-carb guides

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  1. Barb Poelman
    What about monkfruit? I see this in lots of recipes.
  2. Stephanie
    Yes, I'd like to know this as well!

    Stephanie in SF, CA, USA

    (I thought I was hitting a 'like' button on Barb's question above, but it seems that made the comment get 'reported' - didn't mean to do that, if that means I was complaining about it or calling it inappropriate! My apologies!)

  3. Juanjo Camps
    What about cinnamon? Could it be an interesting alternative and "different" type to sweet?
  4. Stan Ruggiero
    I see what appear to be contradicting info regarding Stevia.....make it easy......which brand of powder stevia is appropriate?
  5. Lior
    Hi, Ive been on keto diet for almost 6 years now for various autoimmune conditions , out of those 8 years ive been consuming only pure stevia for at least 3 years. my consumptions is pretty much few coffee drinks through out the day and soda's containing stevia (such as zevia). though up until year and a half ago I've been extremely thin, its not the case anymore. i havnt changed anything in my diet if anything i eat less and less (you get used to it) . however im starting to suspect stevia has really messed up my metabolism and hormone levels! i stopped using it 3 days ago, and its really hard , my taste buds cant feel any flavors without the stevia. i found your website in search for recipes that dont use any sweeteners at all and im super excited, hoping to have stevia behind me, and any sweet foods whatsoever.
    Thank you!
  6. Katherine
    What about Sukrin Gold? Is this a good option? It's ingredients are erythritol, tagatose, glycerin, malt extract and stevial glycocides.
  7. Delia
    What about sorbitol? Is that ok to use? It’s in my VitaminB drops.
  8. Rox
    I love your carb guides but in our area, there are a lot of corn and strawberries grown. These are not listed in your guides - does that mean we need to completely avoid them?
  9. 1 comment removed
  10. Louise
    What about honey?
    Reply: #31
  11. Glenda
    I've been reading about Glycemic Load compared to Glycemic Index? Is this reflected in the photos. For example watermelon has GI of 72 and a GL of 4 for the average serving. Another thing I'm curious about is sweeteners. Although powdered Spenda has lots of other "sugars" in it the liquid version is pure sucralose without anything added to it. So is liquid sucralose better than powdered sucralose?
  12. Tereza
    I didnt find anything about mushrooms. Are they OK?
  13. Alexandra
    Hi! Thank you for your outstanding work Dr. Fung. I was wondering if you could comment about Monk Fruit Sweetener? Thank you
  14. Nichola
    Hi, can anyone tell me if Hermasetas is ok?? I read on another keto website that it is.
  15. Phyllis Peterman
    I have stopped cane sugar, and use honey in my tea. Honey is good for you. Why is this a bad substitute for cane sugar?
  16. Brenda
    There is a newer sweetner replacement called swerve. Is it ok to use on Keto?
    Reply: #20
  17. Becky
    Sucralose seems like a good choice. Liquid.
  18. Jack
    Is EZ sweet ok? It has no carbs.
    Reply: #19
  19. Tailina Garcia
    no its artificial sweetner

    Is EZ sweet ok? It has no carbs.

  20. Tailina Garcia
    yes swerve is erythritol
  21. Sam
    I’m looking for the answer regarding whether sukrin gold is an ok sugar alternative. I’ve been testing this for about a year as we didn’t like the after taste of stevia. It’s easier to replace in recipes as well as it weighs more than stevia.
    Looking forward to hearing more:)
  22. Martina
    I use Inulin for sweet treats of my husband. It is a dietary fiber that has the good side effect to feed beneficial bacteria. But for me any sweet food mess up my blood sugar and produce cravings/kicks me out ketosis. I am not overweighted at all but I do not use it for this reason.
  23. BJ
    Where are the answers to these questions?
  24. Claudine
    I would like to know what your thoughts are about Monkfruit also. There are two other people who had asked the question in February but I didn’t see a response or have missed it.
    I use Lakanto Liquid Monkfruit Extract & have read different things about using it with the Ketogenic diet. Is there anyway you could set the record straight & let us know what your option is. Thanks
  25. Cynthia
    Really hope that the team gets more involved in this topic also since there alot of people who still would enjoy sugerly like items. Have someone ever looked into Yacon? Its REALLY nice and does not spike insuline. Its also natural... https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4963912/ Hope to get a reply on this one...
  26. Darla
    Try this link, there is an update here: https://www.dietdoctor.com/low-carb/keto/sweeteners
  27. Alb
    f you’re not yet convinced that you should stay away from erythritol, there’s more. As of 2014, researchers at Drexel University were pursuing a patent on erythritol as an insecticide and are continuing to study its effectiveness. Yes, that’s right — not only is it low in calories, it’s also really great at killing bugs. I wish I was joking, but I’m not.
    The 2014 study is titled “Erythritol, a Non-Nutritive Sugar Alcohol Sweetener and the Main Component of Truvia®, Is a Palatable Ingested Insecticide.” The researchers show that erythritol is toxic to flies, which are drawn to its sweet flavor, which makes erythritol a “killer combination.” I don’t know about you, but I certainly would rather put some raw honey in my next cup of tea rather than a proven bug killer.
    Reply: #28
  28. Stephanie
    That’s insane... I’m really glad I haven’t used it (or any other artificial sweeteners) since going keto.
  29. Roxanne Jervis
    What about legumes or pulses in the food group diagrams , ie. white kidney beans, chic peas, etc.
    Reply: #30
  30. Kristin Parker Team Diet Doctor

    What about legumes or pulses in the food group diagrams , ie. white kidney beans, chic peas, etc.

    In general, legumes and beans won't be a good fit as they are higher carb and can exacerbate inflammation in the body.

  31. Travis
    Honey is mentioned in the Fructose section of this page.

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