The Complete Guide to Sugar Alcohols
Sugar alcohols are the most common sweeteners in "sugar-free" products. But they're not all created equal. Understanding them helps you make better choices.
What Are Sugar Alcohols?
Sugar alcohols (polyols) are carbohydrates that are neither sugars nor alcohols. They occur naturally in some fruits and are produced commercially through hydrogenation of sugars. They provide fewer calories than sugar because they're only partially absorbed.
The Big Five
Erythritol
- Sweetness: 60–70% of sugar
- Calories: 0
- GI: 0
- GI tolerance: Good (90% absorbed in small intestine)
- Pros: Zero calories, zero glycemic impact, well-tolerated
- Cons: Cooling sensation, crystallization issues, cardiovascular concerns (2023 study)
Xylitol
- Sweetness: 100% (matches sugar)
- Calories: 2.4/g
- GI: 7
- GI tolerance: Moderate (can cause distress above 20g)
- Pros: Matches sugar sweetness, prevents tooth decay, decent baking
- Cons: DEADLY TO DOGS, GI issues, not zero-calorie, has some glycemic impact
Maltitol
- Sweetness: 75% of sugar
- Calories: 2.1/g
- GI: 35
- GI tolerance: POOR (notorious for GI distress)
- Pros: Cheap, widely used commercially
- Cons: Significant blood sugar impact, severe digestive issues common, misleadingly marketed as "sugar-free"
Sorbitol
- Sweetness: 60% of sugar
- Calories: 2.6/g
- GI: 9
- GI tolerance: Poor
- Pros: Inexpensive
- Cons: Major GI issues even at moderate doses, not zero-calorie
Isomalt
- Sweetness: 45–65% of sugar
- Calories: 2/g
- GI: 2
- Pros: Low glycemic, good for hard candy
- Cons: Very poor GI tolerance, less sweet than sugar
The Comparison Table
| Property | Erythritol | Xylitol | Maltitol | Sorbitol | Allulose |
|----------|-----------|---------|----------|---------|----------|
| Calories/g | 0 | 2.4 | 2.1 | 2.6 | 0.2–0.4 |
| GI | 0 | 7 | 35 | 9 | 0 |
| GI tolerance | Good | Moderate | Poor | Poor | Very Good |
| Browning | No | Slight | Slight | No | Excellent |
| Crystallization | Yes | No | No | No | No |
| Dog safe | Yes | NO ☠️ | Yes | Yes | Yes |
| Cooling taste | Yes | Slight | No | Slight | No |
| Baking quality | Fair | Good | Fair | Poor | Excellent |
Why Allulose Is Often Better
Allulose isn't technically a sugar alcohol — it's a rare sugar. But it competes in the same space and wins on most fronts:
- Better taste (no cooling, no aftertaste)
- Better baking (browning, no crystallization)
- Better GI tolerance (minimal digestive issues)
- Zero glycemic impact
- Safe for dogs (unlike xylitol)
- Moisture retention (unlike erythritol)
When Sugar Alcohols Still Make Sense
- Erythritol in beverages: Dissolves well, no bulk needed, cheaper
- Xylitol for dental products: Gum, toothpaste (proven cavity prevention)
- Erythritol-monk fruit blends: Good budget option for everyday sweetening
What to Avoid
Maltitol in any significant quantity. Despite being technically "sugar-free," it raises blood sugar meaningfully and causes severe digestive issues. If a product's first sugar-free ingredient is maltitol, find an alternative.
The Bottom Line
Not all sugar-free sweeteners are equal. Allulose outperforms sugar alcohols in most applications. When buying sugar-free products, check WHICH sweetener is used — the specific choice matters enormously for both your blood sugar and your digestive comfort.