Calcium Propionate vs Polydextrose: which is worse?

What is Calcium Propionate?

Calcium propionate is the calcium salt of propionic acid, a short-chain fatty acid naturally produced during fermentation. It is one of the most widely used mold inhibitors in commercial bread and baked goods. It works by penetrating fungal cells and lowering internal pH to inhibit growth.

What is Polydextrose?

Polydextrose is a synthetic polymer of glucose (with some sorbitol and citric acid) created under heat and vacuum conditions. It functions as a soluble dietary fiber, providing only 1 kcal/g. It is used to add bulk to reduced-calorie foods while also contributing fiber content. The FDA approved it as GRAS in 1981.

Documented risks

Calcium Propionate: Generally recognized as safe. However, a 2012 study in the Journal of Pediatric Child Health (Dengate & Ruben) and a 2019 study published in Science Translational Medicine found that calcium propionate induced insulin resistance in a mouse model and raised metabolic concerns. The 2019 animal study, conducted by Bhatt et al., found that propionate triggered glucagon and norepinephrine secretion. Some open-label human studies and parental reports have linked calcium propionate to irritability, sleep disturbance, and behavioral changes in sensitive children, though these lack robust clinical trial evidence. Most regulatory agencies consider it safe at current use levels.

Polydextrose: At doses above ~90 g/day, polydextrose can cause flatulence, bloating, and loose stools. At normal food use levels it is well tolerated. EFSA confirmed its safety in 2012. It functions as a soluble prebiotic fiber, feeding beneficial gut bacteria. No genotoxicity, carcinogenicity, or reproductive toxicity has been identified.