The Truth About Erythritol and Other Keto Sweeteners: A Fact-Based Guide

Many people are concerned about erythritol right now. They’re concerned because this noncaloric, Keto-friendly sweetener was recently linked to higher risks of major heart events in thousands of humans.[*] 

Should you be worried too? That depends on your definition of worried. 

If you’re being cautious with erythritol for now, that’s sensible. But if you’re panicking because you ate a small cup of erythritol ice cream last Tuesday, you may be overreacting.

We’ll explore why caution (not panic) makes sense as we address the question: “what are the dangers of erythritol?” We’ll also explore the safety of other Keto sweeteners, our sweetener recommendations, and how to think about sweetening responsibly. 

First, though, let’s cover the basics of erythritol. 

What Is Erythritol?

Erythritol is a sweet, indigestible carbohydrate called a sugar alcohol. It’s about 70% as sweet as sugar and contains nearly zero calories.[*] 

Most sugar alcohols (xylitol, sorbitol, etc.) are low in calories because they’re not digested like ordinary carbohydrates. Instead of being absorbed through the small intestine and raising blood sugar, they pass through to the large intestine to become food for gut bacteria. 

Erythritol works differently, though. It does absorb through the small intestine, but it absorbs intact—so you excrete 90% of it through urine.[*] 

That’s why erythritol is nonglycemic (doesn't raise blood sugar) and calorie-free. It’s also why, until recently, we recommended erythritol for low-carb and Keto diets. 

The New Erythritol Study

The February 2023 erythritol paper in Nature Medicine is making waves in the news media.[*] Let’s start with the most reported section: the observational findings. 

The authors looked at several thousand people and found that higher circulating erythritol levels correlated with higher risks of heart attack, stroke, and cardiac death over three years. 

In these situations, it’s helpful to remember that correlation is not causation. Could something else (besides consuming erythritol) explain the link between elevated erythritol levels and heart problems?

Possibly. As it happens, we produce erythritol (in our body) in the presence of inflammation, oxidative stress, diabetes, and other cardiovascular risk factors. 

Were the high erythritol folks eating too many frozen desserts or just sick to begin with? Is consuming erythritol bad for you? The observational data can’t answer these questions.

Yes, the authors statistically controlled for well-known heart disease risk factors, but they didn’t test how much erythritol each person produced naturally. It’s a big fat question mark. 

But wait, there’s more. The researchers also found erythritol increases platelet aggregation in test tubes and mice. (More platelet aggregation means a higher risk of blood clots that precipitate a heart attack or stroke.) 

And here’s the kicker. Feeding eight humans a reasonable 30 grams of erythritol raised blood levels 1000x over baseline (for days) and increased platelet aggregation following ingestion.  

To summarize, we have: 

• Correlational data linking circulating erythritol to heart events
• A mechanism (blood clotting) that might explain the correlation
• Human evidence that consuming regular doses of erythritol raises blood clotting risk

It’s not an iron-clad case against this sugar alcohol. But it’s concerning enough to take erythritol off the recommended list. 

Is Erythritol Safe? And Erythritol Side Effects

The FDA designates erythritol as GRAS (generally recognized as safe.) This designation, however, does not incorporate the recent findings. 

And so, it’s probably wise to avoid erythritol until further notice. The data is strong enough to warrant caution. 

Other sugar alcohols—xylitol, mannitol, maltitol, etc.—have similar safety profiles to erythritol.[*] But again, we don’t know enough about these molecules. 

We do know that xylitol is lethal to dogs.[*] That’s a disturbing factoid, even to self-proclaimed cat people.  

The side effects of erythritol (and sugar alcohols generally) tend to be gastrointestinal. We’re talking about bloating, gas, diarrhea, and the fun social consequences that come along with them. 

Erythritol is usually better tolerated than xylitol, sorbitol, and the rest of the gang. But some folks have bad reactions to any sugar alcohol. 

Fortunately, there are other sugar substitutes available. 

What About Other Keto Sweeteners?

Whether you’re Keto or simply eating healthy, minimizing sugar makes tons of sense. The less sugar you eat, the lower your risk for obesity and a broad spectrum of chronic diseases.[*]  

Many of us turn to noncaloric options to reduce sugar consumption. These Keto sweeteners include:

• Sugar alcohols—especially the nonglycemic erythritol
• Stevia
• Monk fruit 
• Allulose

We covered sugar alcohols already. Proceed with caution. 

Stevia and monk fruit are plant-based, zero-calorie sweeteners with a long history of traditional use.[*] They’re considered safe by the FDA, but (as with erythritol) our knowledge has limits. 

For instance, some worry that stevia is an endocrine disruptor that interferes with sex hormones. This fear, however, is based on test tube data.[*] (Bathing sperm cells in stevia says little about ingesting stevia.) 

Finally, allulose is another GRAS sweetener found in raisins and jackfruit (pass the jackfruit, Agatha!) with little long-term supporting data. It’s become popular because it feels and bakes like sugar, plus it may enhance fat burning after a meal.[*] 

The Sweeteners We Recommend

Before the Nature Medicine study, the data on erythritol was mainly positive.[*] That’s why we—your friendly neighborhood Carb Manager—recommended it. 

Things change. New data arrives. We must update our views. It’s part of staying informed and intellectually honest. 

While we no longer recommend erythritol, we still think consuming limited amounts of stevia, monk fruit, and allulose is okay. But to be on the safe side, use them sparingly. 

Consider sweetening your coffee with stevia 1-2 times weekly. (Not daily.) Make allulose cookies on the holidays. (Not every Friday.) Have monk fruit pudding as a special treat. (Not a post-dinner ritual.)

Understand: higher usage might be healthy—even beneficial. But the erythritol findings highlight the need for prudence in these matters. 

We Don’t Need Sweeteners

For most of human history, people survived without sweeteners. Early hominids weren’t drinking stevia soda. 

We evolved to enjoy sweet things because sweet things (like fruit) were a dense source of calories. And because finding these treats happened infrequently.  

This brings us to an important principle. The more rarely you consume sweet foods, the more you’ll enjoy them. 

It’s the psychology of pleasure. If you eat sweets constantly, your tastes adapt. 

But if you make them a treat, that’s exactly what they’ll be. Scarcity makes everything better. 

You can also use whole food flavors to add a hint of sweetness to your bakes and hot beverages.

Anyways, it’s up to you how to proceed. Although the recent study doesn’t prove erythritol is harmful, it’s a reasonable step to avoid this sugar alcohol going forward. We’ll keep you updated on erythritol (and other Keto sweeteners) so you can continue making informed decisions about your health.