Xylitol vs Sodium Propionate: 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 Sodium Propionate?

Sodium propionate is the sodium salt of propionic acid. Like calcium propionate (E282), it is used as an antimicrobial preservative to prevent mold and bacterial spoilage in bread and baked goods. It is also used in poultry and animal feed applications.

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.

Sodium Propionate: The health profile is essentially the same as calcium propionate. The 2019 Science Translational Medicine study implicating propionate in metabolic changes applies to all propionate salts. Behavioral sensitivity concerns that have been anecdotally reported with calcium propionate may similarly apply. At regulated use levels, sodium propionate is considered safe by global regulatory agencies.