Inulin vs Sorbitol: which is worse?

What is Inulin?

Inulin is a naturally occurring prebiotic dietary fiber (fructan polysaccharide) found in chicory root, Jerusalem artichoke, garlic, onions, and bananas. Commercial inulin is extracted primarily from chicory root. It resists digestion in the small intestine and is fermented by beneficial gut bacteria in the colon, promoting growth of Bifidobacterium and Lactobacillus species.

What is Sorbitol?

Sorbitol is a sugar alcohol (polyol) naturally found in some fruits, including apples, pears, and prunes. Commercially, it is produced by hydrogenation of glucose. It has approximately 60% of the sweetness of sucrose but provides fewer calories (2.6 kcal/g vs 4 kcal/g for sugar) and does not cause a significant immediate insulin response.

Documented risks

Inulin: Generally safe and beneficial. At doses above 15–20 g/day, inulin commonly causes bloating, gas, abdominal cramping, and diarrhea due to rapid fermentation in the colon. This is well documented in peer-reviewed research. It is contraindicated for people with fructan intolerance or irritable bowel syndrome following a low-FODMAP diet. At normal food fortification levels (3–8 g/serving), it is tolerated by most adults.

Sorbitol: At doses above 20–50 g/day, sorbitol can cause osmotic diarrhea because it is incompletely absorbed in the small intestine and is fermented by colonic bacteria. EU regulations require products containing more than 10% added polyols to carry the label 'excessive consumption may produce laxative effects.' This is well-known and predictable. Sorbitol is not carcinogenic and does not raise blood glucose significantly, making it suitable for diabetics in controlled amounts.