Polydextrose vs Allulose: which is worse?

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.

What is Allulose?

Allulose (D-psicose) is a rare sugar monosaccharide naturally present in trace amounts in wheat, figs, raisins, and jackfruit. It has about 70% of sucrose's sweetness but provides only 0.4 kcal/g (about 10% of sucrose's calories) because it is absorbed but not metabolized. The FDA exempted allulose from the 'total sugars' declaration in 2019.

Documented risks

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.

Allulose: Generally considered safe with a favorable glycemic profile. Human studies show that allulose does not raise blood glucose or insulin. GI effects (bloating, abdominal cramping, diarrhea) have been reported in dose-response studies above 0.4 g/kg body weight; a 2016 study in the journal Food & Chemical Toxicology established a no-observed-adverse-effect level (NOAEL) in humans. Compared to erythritol, no cardiovascular concerns have been raised in the literature.