Inulin vs Maltodextrin: 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 Maltodextrin?

Maltodextrin is a polysaccharide derived by partial hydrolysis of starch — most commonly corn starch in the US, but also wheat, potato, or rice starch. It is a white powder with a mild, slightly sweet taste and is highly soluble. Despite being classified as a carbohydrate, maltodextrin has a high glycemic index (GI of 85–105), often higher than table sugar.

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.

Maltodextrin: Maltodextrin's very high glycemic index (GI 85–105) means it causes rapid blood glucose spikes, potentially problematic for people with diabetes or insulin resistance. A 2012 study in PLoS ONE (Bhatt et al.) found that maltodextrin suppressed beneficial gut bacteria (like Lactobacillus) and increased Escherichia coli biofilm formation associated with Crohn's disease. A 2022 study in Nutrients noted maltodextrin's potential to disrupt gut microbiome composition at typical dietary intakes. Regulatory agencies have not restricted its use, but nutrition researchers increasingly flag it as a low-quality carbohydrate.