Xylitol vs Mono- and Diglycerides: 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 Mono- and Diglycerides?

Mono- and diglycerides are emulsifiers derived from glycerol and fatty acids, most commonly sourced from soybean, palm, or sunflower oil. They are partial glycerides that exist between monoglycerides (one fatty acid chain) and diglycerides (two chains). They are chemically similar to fats but are not classified as trans fats even when made from partially hydrogenated sources.

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.

Mono- and Diglycerides: Generally recognized as safe at typical food levels. However, mono- and diglycerides can be derived from partially hydrogenated oils, meaning they may carry trace trans fats that do not appear on the trans fat label because they are classified as emulsifiers, not fats. Some researchers have noted this labeling gap. A 2019 study published in Lipids in Health and Disease noted potential concerns with industrial trans fatty acids in these additives. For most consumers, exposure is low, and regulatory agencies including FDA and EFSA consider them safe at permitted levels.