Fermented gold kiwi also significantly improved the self-reported quality of life of the intervention group as compared to the placebo group.
Writing in Nutrients, the researchers of Semyung University, retail firm RnBS Corporation, and functional ingredient supplier Vitech which also provided the study materials, detailed how the study was conducted on individuals with dyspeptic symptoms, including post-meal fullness, epigastric pain, and epigastric burning.
During the study, 100 participants were randomised to take either 10mL of fermented gold kiwi or placebo once daily for eight weeks.
The gold kiwi used in the intervention was fermented with five bacteria strains, including Lactococcus lactis VI-01 and Lactobacillus acidophilus VIFEC24.
To assess the effect of supplementation, the participants were required to report their gut discomfort symptoms.
This was conducted using the Gastrointestinal Symptom Rating Scale (GSRS) over a scale of seven.
The questionnaire looks at their severity of upper and lower gastrointestinal symptoms, such as abdominal pain, heartburn, acid regurgitation, and stools consistency.
The higher the score, the more troublesome the participants perceive their condition.
Two other surveys, the Korean version of the Nepean Dyspepsia Index (NDI-K) and the Functional Dyspepsia-related Quality of Life were also used.
The former similarly measures functional dyspepsia symptoms, including heartburn, upper abdominal cramps, and acid reflux. Like the GSRS, the higher the score, the more severe the self-perceived symptoms of gut discomfort.
The latter is a 21-item questionnaire to assess the quality of life.
Changes in tumour necrosis factor (TNF)-α and interleukin (IL)-6 concentrations from baseline to week 8 were also measured.
By the end of the trial, both the intervention and placebo group showed significant decrease in their GSRS from the baseline.
However, the decrease was significantly larger for the intervention group than the placebo group at −11.46 ± 7.89 versus −7.64 ± 8.66.
As a result, the intervention group’s GSRS score was lower at 13.65 ± 6.70 than 18.49 ± 9.66 reported in the placebo group.
The researchers noted that the intervention group started to show a significant reduction in GSRS score as early as the first two weeks of the trial.
“The GSRS total score analysis revealed that the FGK (fermented gold kiwi) group showed a significant reduction in symptoms starting at two weeks of intervention and demonstrated greater improvement than the placebo group at four and eight weeks,” they said.
They added that scores for abdominal pain, dyspepsia, and constipation symptoms continued to decrease from week two of the study.
In contrast, only the scores for abdominal pain symptoms continued to decrease from week two for the placebo group.
A similar trend was seen for their NDI-K score, where both groups showed significant decrease from baseline when the trial ended.
Again, the decrease was again significantly larger in the intervention group than the placebo group at −47.85 ± 29.77 versus −32.16 ± 30.88.
As a result, the intervention group’s NDI-K score was 25.06 ± 22.63, lower than the placebo group’s 40.36 ± 34.17 by the end of the trial.
No significant changes in TNF-α and IL-6 concentrations were reported for both groups by the end of the trial.
Quality of life
With greater improvements in self-perceived gut discomfort, the intervention group also reported a significantly higher quality-of-life scores as compared to the placebo.
The improvements were seen across the domains of eating, life vitality, emotional, and social functioning.
However, the researchers also cautioned that the findings, which were from self-reported questionnaires could carry the potential for bias.
Citing previous studies, the researchers said that fermented gold kiwi could improve gastric lesions and reduce gastric fluid volume. These could be reasons for the more significant improvements in the intervention group’s questionnaire results.
“Fermented gold kiwi administration improved gastric lesions, reduced gastric fluid volume, and decreased free acidity, total acidity, and pepsin activity, indicating its potential in preventing and treating gastritis and gastric ulcers. This mechanism is believed to result in symptom relief in the upper gastrointestinal tract,” they said.
At the same time, they also cautioned that the use of self-report questionnaires could carry the potential for bias.
“Study participants may underestimate or overestimate their condition, which can reduce the reliability of the results. To reduce this bias, the use of objective measures or biomarkers is preferred,” they said.
Source: Nutrients
Fermented Gold Kiwi for Improved Gastric Health: Evaluation of Efficacy and Safety in a Randomised, Double-Blind, Placebo-Controlled Trial
https://doi.org/10.3390/nu16162670
Authors: Shin, S.M et al