Calcium oligofructose is a combination of calcium salts and oligofructose, a prebiotic dietary fiber derived from inulin. Its use to support the small intestines is primarily justified by scientific evidence, though the depth and quality of that evidence is moderate. Oligofructose is well-established as a prebiotic, meaning it selectively stimulates the growth and/or activity of beneficial gut bacteria, particularly Bifidobacteria and Lactobacilli, in the colon and distal small intestine. These changes in the gut microbiota can help improve gut health, support the intestinal barrier, and may reduce the risk of some gastrointestinal disorders.

Several clinical studies and reviews have demonstrated that oligofructose increases the production of short-chain fatty acids (SCFAs) like butyrate, acetate, and propionate, which serve as energy sources for colonocytes and contribute to gut integrity and function. While most prebiotic effects are concentrated in the colon, there is evidence that oligofructose fermentation can begin in the distal small intestine, potentially benefiting its environment and function.

The addition of calcium offers the dual benefit of supporting bone health and enhancing the absorption of calcium in the presence of prebiotics, as prebiotic fermentation can increase mineral solubility and uptake in the intestine. Overall, while calcium oligofructose is not a mainstream treatment for small intestinal disorders, its prebiotic actions and potential to enhance mineral absorption are supported by a moderate body of scientific literature.