However, two weeks post-supplementation, cholesterol levels remained significantly lower than baseline only in the oligosaccharide group, suggesting a more sustained effect.
Similarly, low-density lipoprotein (LDL) levels were significantly reduced in the oligosaccharide group after 12 weeks, with the effect persisting for two weeks post-intervention. This effect was not seen in the polysaccharide group.
This study builds on earlier findings, where both supplements, oligosaccharides and polysaccharides, were identified as safe for participants in a two-week study.
The current trial extends these findings, demonstrating long-term safety and efficacy over 12 weeks.
Writing in Food Science and Nutrition, the researchers wrote: “To our knowledge, this is the first study to reveal differential safety and efficacy profiles between β‐Glucan oligosaccharides and polysaccharides, with the oligosaccharides showing a more favourable profile."
Two intervention groups, one placebo
Conducted as a randomised, placebo‐controlled trial, 96 healthy participants aged 20 to 55 years old were equally assigned either β‐glucans oligosaccharides, β‐glucans polysaccharides, or placebo capsules.
β‐glucan polysaccharides were produced through fermentation of the fungi, Ophiocordyceps dipterigena BCC 2073. These polysaccharides then undergo gamma irradiation to produce β‐glucan oligosaccharides.
The β-glucan capsules were manufactured by Asia Star Trade, which also partially funded the study.
Participants consumed the assigned product once daily at 2000mg for 12 weeks.
Data on lipid profile, urinalysis, blood pressure, the occurrence of adverse symptoms, as well as defecation patterns were collected at weeks 4, 8, 12 and two weeks post-supplementation.
Lipid-lowering effect
After 12 weeks, total cholesterol levels decreased significantly for both β‐glucans oligosaccharides and polysaccharides, compared to their baseline values.
However, at week 14, only the oligosaccharides group recorded lower total cholesterol levels compared to baseline.
Findings further showed that 12 weeks of oligosaccharides intake significantly reduced LDL levels, compared to baseline, and this effect persisted for two weeks post‐intervention, something the researchers wrote would “warrant further investigation”. No change was observed in the polysaccharide group.
“Compared to polysaccharides, β‐glucan oligosaccharides are associated with fewer adverse effects and better lipid‐lowering efficacy,” they added.
The researchers also hypothesized that glucans could bind bile acids or increase intestinal viscosity, reduce bile acid reabsorption and enhance fecal bile acid excretion. This means that the body will pull more cholesterol from the blood to make new bile acids, therefore lowering cholesterol levels.
Defecation results
Researchers also analysed defecation patterns and found that the polysaccharides group reported significantly more changes in defecation as compared to the control group. These changes were both positive and negative.
For instance, positive effects included easier defecation and improved bowel movement frequency for constipated individuals, while negative effects included constipation and loose stools. All symptoms were mild.
The researchers pointed out that β‐glucans are soluble fibers known to affect bowel movements and defecation.
“Based on our findings, β‐1,3/1,6‐glucan oligosaccharides produced by gamma irradiation were associated with fewer adverse events compared to β‐glucan polysaccharides.”
Safety
Besides defecation symptoms, no adverse events or changes in body weight, liver or renal function, blood counts, blood glucose levels, urinalysis, or electrocardiogram were observed in any of the groups throughout the study period.
Together, these findings suggest that daily supplementation with 2000 mg of β‐1,3/1,6‐glucan oligosaccharides or polysaccharides for 12 weeks is safe in healthy individuals. Oligosaccharides were associated with better lipid‐lowering efficacy and fewer adverse events, compared to polysaccharides.
Crucially, this study provides baseline data for establishing an acceptable daily intake (ADI) for fungal glucan oligosaccharides and polysaccharides.
Currently, the European Food Safety Authority (EFSA) defines the acceptable daily intake (ADI) of yeast β‐1,3/1,6‐glucan polysaccharides as 375 mg/day for food supplements and 600 mg/day for foods for particular nutritional uses.
Researchers said no safety limits have been established for β‐1,3/1,6‐glucan oligosaccharides, and that β‐glucan from Ophiocordyceps dipterigena is considered a novel food.
In addition, since this trial showed that a daily dose of 2000mg is considered safe, they recommend that future clinical trials evaluate the efficacy of β‐glucan oligosaccharides and polysaccharides in consumer products.
Source: Food science & nutrition, 14(3), e71379. doi: 10.1002/fsn3.71379. “Differential Safety and Lipid Control Efficacy of β-1,3/1,6-Glucan Oligosaccharides and Polysaccharides Derived From Ophiocordyceps dipterigena BCC 2073 in Healthy Volunteers." Authors: Rungraung, N. et al.
