Xylitol vs Invert Sugar: which is worse?

What is Xylitol?

Xylitol is a five-carbon sugar alcohol (pentitol) naturally found in birch wood, corn cobs, fruits, and vegetables. It has the same sweetness as sucrose but provides 40% fewer calories and does not raise blood glucose or insulin levels. Most commercial xylitol is produced from xylose derived from corn cob or hardwood hemicellulose hydrolysis.

What is Invert Sugar?

Invert sugar is a mixture of equal parts glucose and fructose produced by the acid or enzymatic hydrolysis of sucrose. It is sweeter than table sugar by about 25% and has enhanced moisture-retaining properties. Bees naturally produce invert sugar in honey through the enzyme invertase.

Documented risks

Xylitol: Xylitol is safe for humans at normal consumption levels. Like other sugar alcohols, it can cause osmotic diarrhea and gastrointestinal upset at doses above 40–70 g/day. Critically, xylitol is highly toxic to dogs — even small amounts (0.1 g/kg body weight) can cause severe hypoglycemia and hepatic failure in canines, as documented in multiple veterinary case reports. The FDA and ASPCA have both issued warnings about xylitol pet toxicity. For humans, it is well-tolerated and has dental benefits.

Invert Sugar: Invert sugar poses the same metabolic risks as other added sugars. The free fructose component is metabolized directly in the liver, and excessive fructose consumption has been linked to non-alcoholic fatty liver disease, increased triglycerides, and insulin resistance, as documented in multiple reviews including a 2013 paper in Current Opinion in Lipidology. At moderate consumption, it is not specifically more harmful than sucrose. Regulatory agencies worldwide permit its use without restriction.