A recently published pilot study in the journal Frontiers in Nutrition found that a novel short-chain oat fiber supplement was associated with improved post-meal glucose responses and reduced gut symptoms in healthy adults, according to a June 14 report.
The open-label trial involved 63 healthy adults who consumed the low-viscosity oat β-glucan supplement at three different dosages—5, 10, and 20 grams per day—for two weeks. The researchers observed that the supplement was well tolerated across all groups, with no increase in overall gastrointestinal symptom scores. Common symptoms such as gas, bloating, and constipation were generally mild and transient. One participant discontinued due to gastrointestinal symptoms; however, concurrent use of Zofran (ondansetron) made it unclear whether the fiber was responsible.
Over the course of the study, improvements were noted in gut symptoms for participants consuming 5 or 10 grams per day. Constipation also decreased by the end of the intervention period. The authors suggested that short-chain oat fiber's selective fermentation profile may support beneficial gut microbiota while generating less gas compared to other fibers like inulin.
For glycemic outcomes, only 38 participants had suitable data for analysis during a rice challenge test. Results showed peak glucose concentrations decreased over time—by up to 13% after two weeks among those taking 20 grams daily—a reduction comparable to previous research on dietary fibers. The proportion of participants showing improvement increased with higher doses: from 54% at five grams daily to 83% at twenty grams daily. Additionally, more participants spent time within target blood glucose ranges as dosage increased.
The authors noted that total four-hour glycemic exposure did not change significantly, but suggested this could indicate slower or more sustained glucose digestion and absorption rates. They also highlighted possible roles for both non-viscous mechanisms—such as enzyme inhibition—and changes mediated by gut microbiota fermentation producing short-chain fatty acids (SCFAs), which have been linked to anti-inflammatory effects and improved insulin sensitivity.
Despite promising findings regarding safety and potential metabolic benefits over fourteen days in healthy adults, researchers cautioned about several limitations: lack of placebo control; possible confounding factors such as diet or exercise; single testing points per participant; exclusion of people with certain health conditions; and funding from One Bio Inc., which is associated with some authors. Larger trials including individuals with metabolic disorders are needed before broader conclusions can be drawn.
